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Statutory Interpretation: Theories, Tools, and Trends

Statutory Interpretation:
March 10, 2023
Theories, Tools, and Trends
Valerie C. Brannon
In the tripartite structure of the U.S. federal government, it is the job of courts to say what the law
Legislative Attorney
is, as Chief Justice John Marshall announced in 1803. When courts render decisions on the

meaning of statutes, the prevailing view is that a judge’s task is not to make the law, but rather to
interpret the law made by Congress. Proponents of the two main theories of statutory

interpretation—purposivism and textualism—disagree about how judges can best adhere to this
ideal of legislative supremacy. While purposivists argue that courts should prioritize interpretations that advance the statute’s
purpose, textualists maintain that judges should primarily confine their focus to the statute’s text. Courts applying either
theory can encounter interpretive difficulties in disputes that apply a statute in ways Congress may not have anticipated.
Regardless of their interpretive theory, judges use many of the same tools to gather evidence of statutory meaning. Most
frequently, judges rely on five types of interpretive tools. Although both purposivists and textualists may use any of these
five tools, a judge’s theory of statutory interpretation may influence the order in which these tools are applied and how much
weight is given to each tool. The tools overlap and can be used in different ways.
First, judges often begin by looking to the ordinary meaning of the statutory text, asking how a word is understood in
common parlance. Judges may look to dictionaries, books, or databases for evidence of a word’s ordinary usage. Although
this tool is theoretically aligned with textualism, it is commonly used by a wide variety of judges. Nonetheless, judges may
disagree about what a word’s ordinary meaning is, or whether a particular statutory term may instead be a term of art—that
is, a word with a specialized meaning in a particular context or field.
Second, judges interpret specific provisions by looking to their broader statutory context, including the surrounding phrases
and overall structure of the law. This context can inform whether a word’s ordinary meaning applies in the circumstances
covered by the statutory scheme. A judge might look to whether a term or phrase is used elsewhere in the statute in a way
that sheds additional light on a disputed provision. A judge might also ask whether Congress used different language
elsewhere in a meaningful way. Both purposivist and textualist judges tend to use this tool because it can provide textual
evidence of Congress’s meaning and goal.
Third, judges may turn to the canons of construction, which are presumptions about how courts ordinarily read statutes.
Semantic canons focus on text, often reflecting rules of grammar or presumptions about legislative drafting. For instance, the
rule against surplusage tells courts to give each word and clause of a statute operative effect, under the assumption that
Congress chooses words meaningfully. Substantive canons are presumptions about particular outcomes, reflecting a
judgment that Congress would or would not ordinarily want that outcome. For example, one substantive canon instructs that
Congress generally drafts statutes consistently with the Constitution, so that courts should look for interpretations that avoid
constitutional problems. Canons of construction are more closely aligned with textualism than purposivism, although judges
across judicial philosophies have raised questions about whether or when the canons should be applied.
Fourth, judges may look to a statute’s legislative history, or the record of Congress’s deliberations when enacting a law. This
tool is most closely associated with purposivism. Historically, legislative history was primarily used to discover evidence
about Congress’s intent. In a modern analysis, however, legislative history can also be used to support a textual interpretation
or illuminate a law’s scope. Some judges have suggested certain forms of legislative history are more reliable than others,
with committee reports providing stronger evidence of Congress’s understanding of the law than individual floor statements
from non-sponsors, for example.
Finally, a judge might consider statutory implementation: the way a law has been applied in the past, or might be applied in
the future. Judges may look to past agency enforcement of a law, or simply think through how a particular interpretation
might operate. To the extent this tool asks what problem Congress sought to address and how it went about doing that, it
mirrors the traditional purposivist inquiry. This tool is sometimes used by textualist judges too, who may look to statutory
context to consider a law’s operation.
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Contents
Introduction ..................................................................................................................................... 1
Goals of Statutory Interpretation: A Historical Overview ............................................................... 4
Early Years: Natural Law and Formalism ................................................................................. 5
20th Century: Rise of Legal Realism ......................................................................................... 7
Modern Jurisprudence: Responding to Legal Realism.............................................................. 8
Major Theories of Statutory Interpretation .................................................................................... 10
Purposivism ............................................................................................................................. 12
Textualism ............................................................................................................................... 14
Purposivism vs. Textualism In Practice .................................................................................. 16
A Clear Distinction ........................................................................................................... 16
A Convergence of Theories? ............................................................................................. 17
Empiricism and Refinement of the Theories ........................................................................... 19
Tools of Statutory Interpretation.................................................................................................... 20
Ordinary Meaning ................................................................................................................... 21
Statutory Context .................................................................................................................... 25
Canons of Construction ........................................................................................................... 27
Semantic Canons ............................................................................................................... 29
Substantive Canons ........................................................................................................... 31
Justifications: Disrepute, Rehabilitation, and Empirical Studies ...................................... 34
Legislative History .................................................................................................................. 39
Purposes for Using Legislative History ............................................................................ 40
The Debate over Using Legislative History ...................................................................... 41
Statutory Implementation ........................................................................................................ 45
Agency Interpretations ...................................................................................................... 45
Practical Consequences ..................................................................................................... 47
Conclusion ..................................................................................................................................... 48

Figures
Figure 1. Hierarchy of Legislative History .................................................................................... 44

Appendixes
Appendix. Canons of Construction ............................................................................................... 50

Contacts
Author Information ........................................................................................................................ 62

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Introduction
“No vehicles in the park.”

For decades, lawyers have debated the proper scope of this hypothetical law.1 The rule at first
appears admirably straightforward, but thought experiments applying the law quickly reveal
latent complications. Does this law forbid bicycles?2 Baby strollers?3 Golf carts?4 Drones?5 Does
it encompass the service vehicles of the park’s caretakers, or an ambulance responding to a
parkgoer’s injury?6 Would it prevent the city from bringing in a World War II truck and mounting
it on a pedestal as part of a war memorial?7 While many would read the hypothetical law to
prohibit an enthusiastic mother from driving a minivan full of young soccer players into the park,
it may not be so simple to justify that seemingly reasonable interpretation. If the soccer mom
challenged the decision of a hypothetical Department of Parks and Recreation to prohibit her
from entering, how would the Department’s lawyers justify this position? Should they refer
primarily to the law’s text, or to its purpose? What tools should they use to discover the meaning
of the text or the lawmaker’s purpose? How does their theory of interpretation influence their
answers to the harder problems of application?
This deceptively simple hypothetical has endured because it usefully illustrates the challenges of
statutory interpretation. Even a statutory provision that at first appears unambiguous can engender
significant difficulties when applied in the real world. Supreme Court Justice Felix Frankfurter
once aptly described the problem of determining statutory meaning as inherent in “the very nature
of words.”8 The meaning of words depends on the context in which they are used and might
change over time.9 Words are “inexact symbols” of meaning, and even in everyday
communications, it is difficult to achieve one definite meaning.10
These “intrinsic difficulties of language” are heightened in the creation of a statute, which is
crafted by a complicated governmental process and will likely be applied to an unforeseeable
variety of circumstances.11 Statutes are usually written in general terms, which may compound
the difficulty of applying a provision to specific situations.12 However, this generality—and the
ensuing ambiguity—is often intentional: statutes are frequently drafted to address “categories of
conduct.”13 The enacting legislature may have sought to ensure that the statute would be general

1 See, e.g., Frederick Schauer, A Critical Guide to Vehicles in the Park, 83 N.Y.U. L. REV. 1109, 1111–12 (2008)
(revisiting the hypothetical on “the fiftieth anniversary” of a famous debate between the legal scholars H.L.A. Hart and
Lon Fuller that used this example as a focal point).
2 H.L.A. Hart, Positivism and the Separation of Law and Morals, 71 HARV. L. REV. 593, 607 (1958).
3 E.g., FCC v. NextWave Pers. Commc’ns Inc., 537 U.S. 293, 311 (2003) (Breyer, J., dissenting).
4 E.g., Frederick Schauer, Formalism, 97 YALE L.J. 509, 545 (1988).
5 E.g., Brad A. Greenberg, Rethinking Technology Neutrality, 100 MINN. L. REV. 1495, 1530 (2016). Assume the drone
is able to carry objects, or even people—and ask why that matters. See id.
6 E.g., Richard H. Fallon, Jr., The Meaning of Legal “Meaning” and Its Implications for Theories of Legal
Interpretation
, 82 U. CHI. L. REV. 1235, 1260 (2015).
7 Lon L. Fuller, Positivism and Fidelity to Law—A Reply to Professor Hart, 71 HARV. L. REV. 630, 663 (1958).
8 Felix Frankfurter, Some Reflections on the Reading of Statutes, 47 COLUM. L. REV. 527, 528 (1947).
9 See, e.g., ABNER J. MIKVA & ERIC LANE, LEGISLATIVE PROCESS 111 (2d ed. 2002).
10 See Frankfurter, supra note 8, at 528.
11 Id. at 529.
12 See, e.g., MIKVA & LANE, supra note 9, at 111.
13 Id.
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enough to capture the situations it could not foresee,14 or may have intended to delegate
interpretive authority to the agency responsible for enforcing the statute.15 Vague or ambiguous
language might also be the result of compromise.16 Alternatively, a statute might be silent with
respect to a particular application because Congress simply did not anticipate the situation.17
When a statute becomes the subject of a dispute in court, judges usually must interpret the law,
ambiguous or not.18 As Chief Justice John Marshall stated in Marbury v. Madison: “It is
emphatically the province and duty of the judicial department to say what the law is.”19 Judicial
pronouncements about statutes are generally the final word on statutory meaning and will
determine how the law is carried out—at least, unless Congress acts to amend the law. In the
realm of statutory interpretation, many members of the judiciary view their role in “say[ing] what
the law is” as subordinate to Congress’s position as the law’s drafter.20 The legitimacy of any
particular exercise in statutory interpretation is often judged by how well it carries out Congress’s
will.21
Judges have taken a variety of approaches to resolving the meaning of a statute.22 The two
theories of statutory interpretation that predominate today are purposivism and textualism.23
Proponents of both theories generally share the goal of adhering to Congress’s intended meaning,
but disagree about how best to achieve that goal.24 Judges subscribing to these theories may

14 See, e.g., Frankfurter, supra note 8, at 528.
15 See, e.g., MIKVA & LANE, supra note 9, at 111–12.
16 See, e.g., John F. Manning, Textualism and Legislative Intent, 91 VA. L. REV. 419, 445 (2005) (arguing that bills “are
likely to look awkward” because they result from “a legislative process that has many twists and turns”). Cf, e.g.,
Sturgeon v. Frost, 139 S. Ct. 1066, 1083–84, 1087 (2019) (describing a federal law as a “settlement” that sought to
balance two potentially conflicting goals, and rejecting a construction that would “undermine” the law’s “grand
bargain”).
17 See, e.g., HENRY M. HART, JR. & ALBERT M. SACKS, THE LEGAL PROCESS: BASIC PROBLEMS IN THE MAKING AND
APPLICATION OF LAW 1182 (William N. Eskridge, Jr. & Phillip P. Frickey eds., 1994).
18 See, e.g., Cohens v. Virginia, 19 U.S. (6 Wheat.) 264, 404 (1821) (“With whatever doubts, with whatever difficulties,
a case may be attended, we must decide it, if it be brought before us. We have no more right to decline the exercise of
jurisdiction which is given, than to usurp that which is not given.”). Cf. Transcript of Oral Argument at 12, 41, Cyan,
Inc. v. Beaver Cty. Emps. Ret. Fund, No. 15-1439, 2018 U.S. LEXIS 1912 (U.S. 2017) (statements of Justice Samuel
Alito) (describing statutory provision as “gibberish” and asking whether there is “a certain point at which we say this
[provision] means nothing, we can’t figure out what it means, and, therefore, it has no effect”).
19 5 U.S. (1 Cranch) 137, 177 (1803). See also HART & SACKS, supra note 17, at 640 (“Adjudication in its normal
operation is at once a process for settling disputes and a process for making, or declaring, or settling law.”).
20 See, e.g., MIKVA & LANE, supra note 9, at 102 (“All approaches to statutory interpretation are framed by the
constitutional truism that the judicial will must bend to the legislative command.”). See generally Daniel A. Farber,
Statutory Interpretation and Legislative Supremacy, 78 GEO. L.J. 281, 283 (1989) (defining and exploring the concept
of legislative supremacy in the field of statutory interpretation).
21 See, e.g., Jonathan T. Molot, Reexamining Marbury in the Administrative State: A Structural and Institutional
Defense of Judicial Power over Statutory Interpretation
, 96 NW. U. L. REV. 1239, 1251–52 (2002).
22 In a widely read article, Lon Fuller presented a hypothetical dispute from the year 4300 in which five Justices of the
“Supreme Court of Newgarth” split irreconcilably on the proper resolution of a case. Lon L. Fuller, The Case of the
Speluncean Explorers
, 62 HARV. L. REV. 616, 616 (1949). Each Justice issues an opinion that embodies a different
school of interpretation, representing “a microcosm of this century’s debates over the proper way to interpret statutes.”
William N. Eskridge, Jr., The Case of the Speluncean Explorers: Twentieth-Century Statutory Interpretation in a
Nutshell
, 61 GEO. WASH. L. REV. 1731, 1732 (1993).
23 See, e.g., John F. Manning, What Divides Textualists from Purposivists?, 106 COLUM. L. REV. 70, 75 (2006).
24 See, e.g., id. at 91–92. Cf. ANTONIN SCALIA & BRYAN A. GARNER, READING LAW: THE INTERPRETATION OF LEGAL
TEXTS 30 (2012) (arguing against using the word “intent” even if it refers solely to the intent “to be derived solely from
the words of the text” because it “inevitably causes readers to think of subjective intent”). For further discussion of the
ways in which textualists are skeptical about legislative intent, see infra “Textualism.” For a discussion of the possible
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employ different interpretive tools to discover Congress’s meaning,25 looking to the ordinary
meaning of the disputed statutory text,26 its statutory context,27 any applicable interpretive
canons,28 the legislative history of the provision,29 and evidence about how the statute has been or
may be implemented.30
Understanding the theories that govern how judges read statutes can help Congress legislate more
effectively. As a practical matter, judicial opinions interpreting statutes necessarily shape the way
those statutes are implemented. If Congress knows how courts ascribe meaning to statutory text,
it might be able to eliminate some ambiguity regarding its meaning by drafting according to the
predominant legal theories.31 If Congress follows courts’ methodologies for statutory
interpretation, it may better communicate its policy choices not only to courts, but also to the
general public. Members of the public frequently interpret statutes in the same way as courts,
whether because they look to courts as the final arbiters of statutes or because courts often
intentionally mimic general understandings of how language is naturally interpreted.32 Finally, as
this report discusses in detail, judges and legal scholars are engaged in an ongoing and evolving
debate over the best way to determine the meaning of statutes.33 For Members of Congress and
their staff to participate meaningfully in this discussion, they must be aware of the scope and
intricacies of that debate.
To help provide Congress with a general understanding of how courts interpret statutory
language, this report begins by discussing the general goals of statutory interpretation, reviewing
a variety of contemporary and historical approaches. The report then describes the two primary
theories of interpretation employed today, before examining the main types of tools that courts
use to determine statutory meaning. A separate CRS report explores in more detail the rules and
presumptions that govern the construction of common components of federal legislation, such as
legislative findings or severability clauses.34

distinction between “purpose” and “intent,” see note 111.
25 See, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 84–85.
26 See discussion infra “Ordinary Meaning.”
27 See discussion infra “Statutory Context.”
28 See discussion infra “Canons of Construction.
29 See discussion infra “Legislative History.”
30 See discussion infra “Statutory Implementation.”
31 See, e.g., John F. Manning, Inside Congress’s Mind, 115 COLUM. L. REV. 1911, 1932–33 (2015) (noting that some
versions of textualism emphasize the importance of creating “clear interpretive rules” as a background against which
Congress may legislate (quoting Finley v. United States, 490 U.S. 545, 556 (1989))).
32 See, e.g., Stephen Breyer, On the Uses of Legislative History in Interpreting Statutes, 65 S. CAL. L. REV. 845, 847
(1992) (noting that his purposivist interpretive theory incorporates “widely shared substantive values, such as helping
to achieve justice by interpreting the law in accordance with the ‘reasonable expectations’ of those to whom it applies”
(citation omitted)); John F. Manning, Textualism and the Equity of the Statute, 101 COLUM. L. REV. 1, 109 (2001)
(noting that textualists ask how a “reasonable user of words would have understood the statutory text” (internal
quotation mark omitted)).
33 E.g., William Baude & Stephen E. Sachs, The Law of Interpretation, 130 HARV. L. REV. 1079, 1116 (2017).
34 CRS Report R46484, Understanding Federal Legislation: A Section-by-Section Guide to Key Legal Considerations,
by Victoria L. Killion.
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Goals of Statutory Interpretation:
A Historical Overview
Courts “say what the law is”35 by resolving legal disputes in individual cases.36 This is true
whether a court is interpreting a positive law, such as a statute or regulation, or reasoning from a
prior judicial precedent.37 In the latter instance, a court is drawing from a body of law known as
the common law. In the historical common-law tradition of making law through judicial opinions,
a court reasons by example, applying general “principles of equity, natural justice, and . . . public
policy” to the specific circumstances before the court.38 Case by case, a common-law court
decides whether each set of circumstances should follow the rule of a previous decision.39 But in
resolving a statutory dispute, courts generally do not simply determine, based on equity or natural
justice, what would have been a reasonable course of action under the circumstances.40 Instead,
the court must “figure out what the statute means” and apply the statutory law to resolve the
dispute.41
The predominant view of a judge’s proper role in statutory interpretation is one of “legislative
supremacy.”42 This theory holds that when a court interprets a federal statute, it seeks “to give
effect to the intent of Congress.”43 Under this view, judges attempt to act as “faithful agents” of
Congress.44 They “are not free to simply substitute their policy views for those of the legislature
that enacted the statute.”45 This belief is rooted in the constitutional separation of powers: in the
realm of legislation, the Constitution gives Congress, not courts, the power to make the law.46 The

35 Marbury v. Madison, 5 U.S. (1 Cranch) 137, 177 (1803).
36 See, e.g., BENJAMIN N. CARDOZO, THE NATURE OF THE JUDICIAL PROCESS 24–25 (1928). See also, e.g., Muskrat v.
United States, 219 U.S. 346, 361 (1911) (“[J]udicial power . . . is the right to determine actual controversies arising
between adverse litigants, duly instituted in courts of proper jurisdiction.”).
37 E.g., HART & SACKS, supra note 17, at 640.
38 Norway Plains Co. v. Boston & Me. R.R., 67 Mass. 263, 267–68 (1854). See also CARDOZO, supra note 36, at 28
(“[T]he problem which confronts the judge is in reality a twofold one: he must first extract from the precedents the
underlying principle, the ratio decidendi; he must then determine the path or direction along which the principle is to
move and develop, if it is not to wither and die.”).
39 See Edward H. Levi, An Introduction to Legal Reasoning, 15 U. CHI. L. REV. 501, 501–02 (1948). See also, e.g.,
Rogers v. Tennessee, 532 U.S. 451, 461 (2001) (“In the context of common law doctrines . . . , there often arises a need
to clarify or even to reevaluate prior opinions as new circumstances and fact patterns present themselves. Such judicial
acts, whether they be characterized as ‘making’ or ‘finding’ the law, are a necessary part of the judicial business . . . .”).
40 WILLIAM N. ESKRIDGE, JR., PHILLIP P. FRICKEY & ELIZABETH GARRETT, LEGISLATION AND STATUTORY
INTERPRETATION 5 (2d ed. 2006) (contrasting common law approach to statutory interpretation). Cf. generally Jeffrey
A. Pojanowski, Reading Statutes in the Common Law Tradition, 101 VA. L. REV. 1357 (2015) (describing various
arguments for and against applying common law principles of reasoning to statutory interpretation).
41 ESKRIDGE ET AL., supra note 40, at 5.
42 See, e.g., John F. Manning, Without the Pretense of Legislative Intent, 130 HARV. L. REV. 2397, 2413, 2425 (2017).
43 United States v. Am. Trucking Ass’ns, Inc., 310 U.S. 534, 542 (1940). See also, e.g., Manning, Textualism and
Legislative Intent
, supra note 16, at 423 (“In any system predicated on legislative supremacy, a faithful agent will of
course seek the legislature’s intended meaning in some sense . . . .”). Manning goes on to explain, however, that
textualists do not “practice intentionalism,” because they seek an objective meaning rather than Congress’s actual
intent. Id. at 423–24. For further discussion of this point, see infra “Textualism.
44 See, e.g., Jonathan T. Molot, The Rise and Fall of Textualism, 106 COLUM. L. REV. 1, 10 n.26 (2006) (citing a
number of “works supporting the faithful agent theory”). See also ESKRIDGE ET AL., supra note 40, at 5–8 (exploring
various conceptions of “faithful agent” role).
45 MIKVA & LANE, supra note 9, at 103.
46 See, e.g., United Steelworkers of Am., AFL-CIO-CLC v. Weber, 443 U.S. 193, 216 (1979) (Burger, C.J., dissenting)
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judicial power vested in the courts entails only “the power to pronounce the law as Congress has
enacted it.”47 Accordingly, courts must remain faithful to what the legislature enacted.48
It was not always the case that judges described their role in statutory interpretation as being so
constrained. This section broadly reviews the evolution of statutory interpretation in U.S. courts,
noting the various schools of legal thought that predominated at particular periods in the nation’s
history. However, while these other interpretive theories no longer represent a majority view, all
continue to exist in some form today, and critically, they influenced the development of the
theories that do dominate modern legal theory.
Early Years: Natural Law and Formalism
Legal thinking in this country’s early years was influenced by the idea of natural law,49 which is
the belief that law consists of a set of objectively correct principles derived “from a universalized
conception of human nature or divine justice.”50 The goal of judges in a natural law system51 is to
“conform man-made law to those natural law principles.”52 Accordingly, courts looked to “the
equity of the statute,”53 seeking to find “the reason or final cause of the law” in order to address
“the mischief for which the common law did not provide,” but the newly enacted statute did, “and
to add life to the cure and remedy, according to the true intent of the makers of the act.”54

(“The Court reaches a result I would be inclined to vote for were I a Member of Congress considering a proposed
amendment of [the disputed act]. I cannot join the Court’s judgment, however, because it is contrary to the explicit
language of the statute and arrived at by means wholly incompatible with long-established principles of separation of
powers.”); Levi, supra note 39, at 520 (“[The words of a statute] are not to be taken lightly since they express the will
of the legislature. The legislature is the law-making body.”). See also Molot, Reexamining Marbury, supra note 21, at
1250–54 (examining Founders’ conceptions of the judicial power).
47 King v. Burwell, 576 U.S. 473, 515 (2015) (Scalia, J., dissenting).
48 See, e.g., HART & SACKS, supra note 17, at 1194–95.
49 See generally Kirk A. Kennedy, Reaffirming the Natural Law Jurisprudence of Justice Clarence Thomas, 9 REGENT
U. L. REV. 33, 41–50 (1997) (exploring the history and development of various strains of natural law). See also, e.g.,
CARDOZO, supra note 36, at 124–25 (“The theory of the older writers was that judges did not legislate at all. A
preexisting rule was there, imbedded, if concealed, in the body of the customary law. All that the judges did, was to
throw off the wrappings, and expose the statute to our view.”).
50 BLACK’S LAW DICTIONARY (10th ed. 2014). See also RICHARD A. POSNER, THE PROBLEMS OF JURISPRUDENCE 5
(1990) (defining natural law as “the idea that there is a body of suprapolitical principles that underwrite ‘positive law,’
meaning law laid down by courts, legislatures, or other state organs”).
51 Natural law was not the only prominent view of statutory interpretation in the early history of American law.
Notably, many subscribed to what was sometimes dubbed (mostly by its detractors) as “literalism.” See United States v.
Dotterweich, 320 U.S. 277, 284 (1943); Learned Hand, How Far Is a Judge Free in Rendering a Decision?, in THE
SPIRIT OF LIBERTY: PAPERS AND ADDRESSES OF LEARNED HAND 107 (Irving Dilliard ed., 1952). Literalism refused to
consider any sense of purpose that was not strictly grounded in the text. See William S. Jordan, III, Legislative History
and Statutory Interpretation: The Relevance of English Practice
, 29 U.S.F. L. REV. 1, 4 (1994) (“[T]he literal rule [in
English law] holds that the intent of Parliament is determined from the actual words of the statute. If Parliament’s
meaning is clear, that meaning is binding no matter how absurd the result may seem.”). See, e.g., Caminetti v. United
States, 242 U.S. 470, 485 (1917) (“Where the language is plain and admits of no more than one meaning the duty of
interpretation does not arise and the rules which are to aid doubtful meanings need no discussion.”).
52 Manning, Textualism and the Equity of the Statute, supra note 32, at 29.
53 Id. at 29–32.
54 J. Clark Kelso & Charles D. Kelso, Statutory Interpretation: Four Theories in Disarray, 53 SMU L. REV. 81, 88
(2000).
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A distinct, but not mutually exclusive,55 view of the law that gained popularity in the 19th
century,56 formalism, posits that “the correct outcome of a case could be deduced” scientifically
from fundamental “principles of common law” contained in prior cases.57 These early formalists
believed that they could use established forms of logic, based on these fundamental common-law
principles, to determine the meaning of statutory text.58
Both natural law and formalism share the belief that the law provides one right answer to any
question and lawmakers can discover that answer.59 For those who subscribed to these schools of
thought, the source of this answer is neither the legislature nor the courts, but the higher
principles of law themselves.60 When natural law and formalism dominated legal thinking, “it did
not matter as much whether judges conceived of themselves as faithful agents of Congress or
coequal partners in law elaboration.”61 This is because under these theories, both courts and
legislators are engaged in the same process of finding the one correct answer.62 And if courts
discover the answer to the legal question presented, proponents of natural law and formalism
contend that there is no need to defer to the legislature.63 Accordingly, under these theories, courts
might resort to equity or reason over a strict construction of the language of the statute because
this gloss on the legislative text amounts to a “correction” of a defective statute, a correction that

55 Formalism represents a certain way of reasoning and could be adopted in tandem with natural law approaches. See,
e.g.
, POSNER, THE PROBLEMS OF JURISPRUDENCE, supra note 50, at 11. However, it is arguably more often associated
with a more “literal” view of statutes—at least in its more modern formulations. See, e.g., Daniel Farber, The Ages of
American Formalism
, 90 NW. U. L. REV. 89, 91 (1995) (“Formalists believe that certainty, stability, and logic are the
primary values to be sought by judges . . . . To implement these values, they embrace formalist methods, such as
textualism as a system for interpreting statutes . . . .”). Cf. Richard H. Pildes, Forms of Formalism, 66 U. CHI. L. REV.
607, 620 (1999) (“Rule-following in the sense of textual literalism was indeed an aspect of classical formalism—as it is
likely to be of any body of American legal thought—but it was a marginal concern. Formalism was a project of
rationalizing the central principles and methods of the common law . . . .”).
56 Molot, The Rise and Fall of Textualism, supra note 44, at 12.
57 POSNER, THE PROBLEMS OF JURISPRUDENCE, supra note 50, at 15.
58 Thomas C. Grey, Langdell’s Orthodoxy, 45 U. PITT. L. REV. 1, 4–5 (1983). See also Richard A. Posner, Legal
Formalism, Legal Realism, and the Interpretation of Statutes and the Constitution
, 37 CASE W. RES. L. REV. 179, 181
(1987) (defining formalism in contrast to other scholars as “the use of deductive logic to derive the outcome of a case
from premises accepted as authoritative”).
59 See Lon L. Fuller, A Rejoinder to Professor Nagel, 3 NAT. L. F. 83, 84 (1958) (“It is an acceptance of the possibility
of ‘discovery’ in the moral realm that seems to me to distinguish all the theories of natural law from opposing views.”);
Pildes, supra note 55, at 608–09 (“To the classical formalists, law . . . meant a scientific system of rules and institutions
that were complete in that the system made right answers available in all cases; formal in that right answers could be
derived from the autonomous, logical working out of the system; conceptually ordered in that ground-level rules could
all be derived from a few fundamental principles; and socially acceptable in that the legal system generated normative
allegiance.”).
60 See generally G. EDWARD WHITE, THE AMERICAN JUDICIAL TRADITION: PROFILES OF LEADING AMERICAN JUDGES 2
(1978) (arguing that in the 19th century, “law was conceived of as a mystical body of permanent truths, and the judge
was seen as one who declared what those truths were and made them intelligible—as an oracle who ‘found’ and
interpreted the law”).
61 Molot, The Rise and Fall of Textualism, supra note 44, at 12.
62 Id.
63 See, e.g., Frank E. Horack, Jr., In the Name of Legislative Intention, 38 W. VA. L.Q. 119, 119 (1932) (“Jeffersonian
conceptions of individual freedom and equality have kept alive the doctrine that our government is one of laws and not
of man. In this idea there is safety, for if law is justice and judicial opinions are produced, cellophane wrapped, by
some monotonously automatic process which man cannot disturb, then man lives ‘non sub homine sed sub deo et lege
[not under man, but under God and law], and is free from mortal tyranny.”). See also Molot, The Rise and Fall of
Textualism
, supra note 44, at 12 (“The rise of formalism and heightened confidence in the constraining force of natural
law principles enabled the federal courts to be very aggressive in their search for legal meaning and yet to be relatively
unconcerned about exceeding their constitutional role or interfering with legislative supremacy.”).
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would not have been necessary “if the original had been correctly stated.”64 As a result, a
prevalent view in the 19th century was that the judge merely said “what the legislator himself
would have said had he been present, and would have put into his law if he had known.”65
20th Century: Rise of Legal Realism
Critically, then, the legitimacy of the theories that primarily governed early American
jurisprudence hinged on the belief that a judge could divine the law by focusing on general
principles of justice or logic.66 As the school of legal realism gained traction in the early 20th
century, however, legal scholars began to question these assumptions and called for judges to
more self-consciously justify the legitimacy of their rulings.67 The early legal realists sought to
discover “how law ‘really’ operated,”68 applying new insights from the fields of sociology and
psychology to judicial decisionmaking.69 Legal realism led to the widespread recognition that
judges sometimes make law, rather than discover it.70 As a result, judges more readily
acknowledged that there were no “pre-established truths of universal and inflexible validity”—or
at least, that they could not divine those truths and invariably derive from them the proper
conclusion in any given case.71 For legal realists, there is “no single right and accurate way of
reading one case.”72 Accordingly, the need arose for judges to more openly justify the law that
they announced in any given case.73 Given the indeterminacy of the legal rules used in formalism,
realists called for new rules they believed would better constrain judges and prevent arbitrary
action.74

64 William H. Loyd, The Equity of a Statute, 58 U. PA. L. REV. 76, 77 n.8 (1909).
65 Manning, Textualism and the Equity of the Statute, supra note 32, at 4 n.6 (quoting THE NICOMACHEAN ETHICS OF
ARISTOTLE 133 (Sir David Ross trans., 1925)).
66 See, e.g., Levi, supra note 39, at 501 (“The pretense [of legal reasoning] is that the law is a system of known rules
applied by a judge . . . .”).
67 See generally Lon L. Fuller, Reason and Fiat in Case Law, 59 HARV. L. REV. 376 (1946); Oliver Wendell Holmes,
The Theory of Legal Interpretation, 12 HARV. L. REV. 417 (1899); Horack, supra note 63; Levi, supra note 39; Roscoe
Pound, Spurious Interpretation, 7 COLUM. L. REV. 379 (1907); John Willis, Statute Interpretation in a Nutshell, 16
CAN. B. REV. 1 (1938). See, e.g., CARDOZO, supra note 36, at 41 (“The logic of [one] principle prevailed over the logic
of the others. . . . The thing which really interests us, however, is why and how the choice was made between one logic
and another. In this instance, the reason is not obscure. One path was followed . . . because of the conviction in the
judicial mind that the one selected led to justice.”).
68 Frederick Schauer, The Limited Domain of the Law, 90 VA. L. REV. 1909, 1912 (2004).
69 Id. at 1911, 1923.
70 See, e.g., CARDOZO, supra note 36, at 128 (“Obscurity of statute . . . may leave the law unsettled, and cast a duty
upon the courts to declare it retrospectively in the exercise of a power frankly legislative in function.”).
71 Id. at 22–23. See, e.g., Black & White Taxicab & Transfer Co. v. Brown & Yellow Taxicab & Transfer Co., 276 U.S.
518, 533 (1928) (Holmes, J., dissenting) (“If there were such a transcendental body of law outside of any particular
State but obligatory within it unless and until changed by statute, the Courts of the United States might be right in using
their independent judgment as to what it was. But there is no such body of law. The fallacy and illusion that I think
exist consist in supposing that there is this outside thing to be found. Law . . . does not exist without some definite
authority behind it.”).
72 Karl N. Llewellyn, Remarks on the Theory of Appellate Decision and the Rules or Canons about How Statutes Are to
Be Construed
, 3 VAND. L. REV. 395, 395 (1950).
73 See, e.g., Fuller, Reason and Fiat in Case Law, supra note 67, at 378.
74 See, e.g., Joseph William Singer, Legal Realism Now, 76 CALIF. L. REV. 467, 470–71 (1988) (reviewing LAURA
KALMAN, LEGAL REALISM AT YALE: 1927-1960 (1986)).
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Modern Jurisprudence: Responding to Legal Realism
In the field of statutory interpretation in particular, legal scholars and judges responded to legal
realism in part by distinguishing the law-making role of the legislature from the law-interpreting
role of the court.75 In this realm especially, “law” was not some platonic ideal, but instead was the
statute that Congress had passed.76 Justice Oliver Wendell Holmes famously expressed this shift
in prevailing legal theory when he stated, “[t]he common law is not a brooding omnipresence in
the sky but the articulate voice of some sovereign or quasi sovereign that can be identified.”77
Judges noted that the Constitution itself restrained judicial discretion by designating Congress,
not the courts, as the lawmaking branch.78 Further, because Congress made the law, judges argued
that they should restrain themselves to act “as merely the translator of another’s command.”79 As
Justice Frankfurter asserted: “In a democracy the legislative impulse and its expression should
come from those popularly chosen to legislate, and equipped to devise policy, as courts are not.”80
Rather than seeking to discover foundational principles of the law, as determined by judges, many
legal theorists argued that courts should instead attempt “to discover the rule which the law-
maker intended to establish; to discover the intention with which the law-maker made the rule, or
the sense which he attached to the words wherein the rule is expressed.”81 To do otherwise was to
risk attempting to make policy, usurping the legislative function.82 Today it is widely accepted
that it is inappropriate for judges to prioritize their own policy views over the policy actually

75 See, e.g., Horack, supra note 63, at 121 (“The problem of interpretation when applied in the field of government
arises because the legislature makes the law and the courts apply it. And since the departmentalization of government,
the task of applying generalized standards of conduct to particularized consequences makes even an honest difference
of opinion inevitable.”).
76 See, e.g., Levi, supra note 39, at 501, 520.
77 S. Pac. Co. v. Jensen, 244 U.S. 205, 222 (1917) (Holmes, J., dissenting). As one scholar pointed out, the fact that
statutes, in particular, were made through public, political processes meant that the law was “no longer the mysterious
thing it was once.” Pound, supra note 67, at 384–85.
78 See, e.g., HART & SACKS, supra note 17, at 1374 (arguing courts should “[r]espect the position of the legislature as
the chief policy-determining agency of the society”); Manning, Textualism and the Equity of the Statute, supra note 32,
at 57 (arguing “that the U.S. Constitution rejected English structural assumptions in ways that make the equity of the
statute an inappropriate foundation for the ‘judicial Power of the United States’”). Cf. Steven P. Croley, The
Majoritarian Difficulty: Elective Judiciaries and the Rule of Law
, 62 U. CHI. L. REV. 689, 693 (1995) (discussing the
problem of “the countermajoritarian difficulty” proposed by Alexander Bickel, which notes the tension inherent in “the
exercise of power possessed by judges neither placed in office by the majority nor directly accountable to the majority
to invalidate majoritarian policies” (internal quotation marks omitted)).
79 Frankfurter, supra note 8, at 534.
80 Id. at 545. See, e.g., Int’l News Serv. v. Associated Press, 248 U.S. 215, 267 (1918) (Brandeis, J., dissenting)
(“Courts are ill-equipped to make the investigations which should precede a determination of the limitations which
should be set upon any property right in news or of the circumstances under which news gathered by a private agency
should be deemed affected with a public interest.”).
81 Pound, supra note 67, at 381. As will be discussed in more detail, infra “Major Theories of Statutory Interpretation,
both purposivists and textualists pursue an objective legislative intent, rather than Congress’s actual intent.
82 See Frankfurter, supra note 8, at 533 (“[Courts] are confined by the nature and scope of the judicial function in its
particular exercise in the field of interpretation. . . . [T]he function in construing a statute is to ascertain the meaning of
words used by the legislature. To go beyond it is to usurp a power which our democracy has lodged in its elected
legislature.”); Pound, supra note 67, at 382 (“[T]he object of spurious interpretation is to make, unmake, or remake,
and not merely to discover. . . . It is essentially a legislative, not a judicial process . . . .”).
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codified by the legislature.83 This general view undergirds both modern purposivism and modern
textualism.84
Not all legal scholars and judges, however, reacted to legal realism by adopting a view of
legislative supremacy in statutory interpretation. Some others argued instead that if judges make
law, they should openly embrace this role and seek to make good law.85 This school of thought,
which continues today, points out that the Constitution has granted to judges the power of
interpretation and argues that the constitutional duty of interpretation entails a meaningful duty to
shape the law.86 For example, one legal scholar has claimed that the Constitution purposefully
“divorces statutory interpretation (given to the executive and the courts in articles II and III) from
statutory enactment (by Congress under article I),” in order to ensure “that statutes will evolve
because the perspective of the interpreter will be different from that of the legislator.”87
At least one commentator has characterized this theory of “pragmatic dynamism”88 as a revival of
the natural law tradition of equitable interpretation.89 Judge Guido Calabresi, while a professor at

83 See, e.g., Kimble v. Marvel Entm’t, 576 U.S. 446, 464–65 (2015) (rejecting certain arguments regarding statutory
meaning as “more appropriately addressed to Congress,” citing “rule of law values” (quoting Halliburton Co. v. Erica
P. John Fund, Inc., 573 U.S. 258, 27 (2014) (internal quotation marks omitted)); Petrella v. Metro-Goldwyn-Mayer,
Inc., 572 U.S. 663, 667 (2014) (“[C]ourts are not at liberty to jettison Congress’ judgment[.]”). See generally, e.g., Jane
S. Schacter, Metademocracy: The Changing Structure of Legitimacy in Statutory Interpretation, 108 HARV. L. REV.
593, 593–94 (1995).
84 See, e.g., HART & SACKS, supra note 17, at 1194 (arguing the principle of institutional settlement “obviously, forbids
a court to substitute its own ideas for what the legislature has duly enacted”); Antonin Scalia, Common-Law Courts in a
Civil-Law System: The Role of United States Federal Courts in Interpreting the Constitution and Laws
, in A MATTER
OF INTERPRETATION: FEDERAL COURTS AND THE LAW 22 (Amy Gutmann ed., 1997) (“It is simply not compatible with
democratic theory that laws mean whatever they ought to mean, and that unelected judges decide what that is.”). See
also, e.g.
, Manning, Textualism and Legislative Intent, supra note 16, at 430 n.34 (“Textualists implicitly build on the
influential work of legal realist Max Radin.”).
85 See, e.g., Fuller, A Rejoinder to Professor Nagel, supra note 59, at 84 (rejecting “the notion that there is a ‘higher
law’ transcending the concerns of this life” but defending the “one central aim common to all the schools of natural
law, that of discovering those principles of social order which will enable men to attain a satisfactory life in common”
through a collaborative process to establish these shared purposes).
86 E.g., CARDOZO, supra note 36, at 133 (“[T]he judge is under a duty, within the limits of his power of innovation, to
maintain a relation between law and morals . . . .”); id. at 135 (“You may say that there is no assurance that judges will
interpret the mores of their day more wisely and truly than other men. . . . [This] is quite beside the point. The point is
rather that this power of interpretation must be lodged somewhere, and the custom of the constitution has lodged it in
the judges.”).
87 WILLIAM N. ESKRIDGE, JR., DYNAMIC STATUTORY INTERPRETATION 58 (1994). Eskridge argued that this conception
of the Constitution is consistent with the framers’ intentions, claiming that they believed “in the productivity of
evolving interpretation to meet new circumstances.” Id. at 117. But see Manning, Textualism and the Equity of the
Statute
, supra note 32, at 82 (“I believe that, properly understood, The Federalist in fact contradicts the assumptions
underlying the equity of the statute.”). In turn, Eskridge responded to Manning’s article in All About Words: Early
Understandings of the “Judicial Power” in Statutory Interpretation, 1776–1806
, 101 COLUM. L. REV. 990, 994 (2001).
88 ESKRIDGE, supra note 87, at 50. Eskridge argued that a statute’s meaning only becomes clear through application,
and that this application “engenders dynamic interpretations”: “When successive applications of the statute occur in
contexts not anticipated by its authors, the statute’s meaning evolves beyond original expectations. Indeed, sometimes
subsequent applications reveal that factual or legal assumptions of the original statute have become (or were originally)
erroneous; then the statute’s meaning often evolves against its original expectations.” Id. at 49.
In taking a dynamic approach to statutory meaning, pragmatists believe that the meaning of a statute evolves over time.
See, e.g., ESKRIDGE, supra note 87, at 50; Hively v. Ivy Tech Cmty. Coll. of Ind., 853 F.3d 339, 352 (7th Cir. 2017)
(Posner, J., concurring). Other judges, however, including many purposivists and textualists, subscribe to a more static
view of statutory meaning, looking instead to the text’s original meaning at the time of enactment. See, e.g., Carlos E.
Gonzalez, Reinterpreting Statutory Interpretation, 74 N.C. L. REV. 585, 626 (1996). Although this temporal distinction
is an important part of some interpretive theories, this report does not discuss the issue further.
89 See Manning, Textualism and the Equity of the Statute, supra note 32, at 81. See also United States v. Marshall, 908
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Yale Law School, argued that judges should take an active role in determining whether statutes
are “out of phase with the whole legal framework,”90 and should have “the authority to treat
statutes as if they were no more and no less than part of the common law.”91 Former federal judge
Richard Posner, another pragmatist,92 has similarly argued that judges should take into account
their “intuitions” or “preconceptions,”93 and look to the practical consequences of their decisions
in determining how to read a statute.94
Major Theories of Statutory Interpretation
The two predominant theories of statutory interpretation today are purposivism and textualism—
although, as explored below,95 some have argued that the two theories are converging.96 As
previously discussed, both theories share the same general goal of faithfully interpreting statutes
enacted by Congress.97 This goal is grounded in the belief that the Constitution makes Congress
the supreme legislator and that statutory interpretation should respect this legislative supremacy.98
Interpretive problems arise, however, when courts attempt to determine how Congress meant to
resolve the particular situation before the court.99 The actual intent of the legislature that passed a

F.2d 1312, 1335–36 (7th Cir. 1990) (Posner, J., dissenting) (arguing that an “irrational” statutory sentencing scheme
highlights “the disagreement between the severely positivistic view that the content of law is exhausted in clear,
explicit, and definite enactments by or under express delegation from legislatures, and the natural lawyer’s or legal
pragmatist’s view that the practice of interpretation and the general terms of the Constitution (such as ‘equal protection
of the laws’) authorize judges to enrich positive law with the moral values and practical concerns of civilized society”).
90 GUIDO CALABRESI, A COMMON LAW FOR THE AGE OF STATUTES 164 (1982).
91 Id. at 2. Judge Calabresi also pioneered the field of law and economics, later taken up by (among others) Judge
Richard Posner. Richard A. Posner, The Economic Approach to Law, 53 TEX. L. REV. 757, 759 (1975). Law and
economics seeks to apply the fundamental insights of economics to analyze law. E.g., POSNER, THE PROBLEMS OF
JURISPRUDENCE, supra note 50, at 353 (“The basic assumption of economics that guides the . . . economic analysis of
law . . . is that people are rational maximizers of their satisfactions . . . .”).
92 See, e.g., RICHARD A. POSNER, THE PROBLEMATICS OF MORAL AND LEGAL THEORY 241 (1999) (defining “pragmatic
adjudication” to include judges who “always try to do the best they can do for the present and the future, unchecked by
any felt duty to secure consistency in principle with what other officials have done in the past” (quotation mark
omitted)). See also id. (contrasting pragmatic judges with “legal positivist[s]” who believe “that the law is a system of
rules laid down by legislatures and merely applied by judges”).
93 POSNER, THE PROBLEMS OF JURISPRUDENCE, supra note 50, at 124–25.
94 Id. at 460 (“The essence of interpretive decision making is considering the consequences of alternative decisions.”);
id. at 462 (arguing that “legal advocates” should emphasize facts and policy and that “judges should at long last
abandon . . . formalist adjudication”).
95 Infra “A Convergence of Theories?”
96 There are a variety of ways to characterize various approaches to the law. See, e.g., Guido Calabresi, An Introduction
to Legal Thought: Four Approaches to Law and to the Allocation of Body Parts
, 55 STAN. L. REV. 2113 (2003)
(categorizing schools of law on the basis of whether and how they incorporate nonlegal disciplines).
97 See supra notes 42 to 48 and accompanying text.
98 Manning, Without the Pretense of Legislative Intent, supra note 42, at 2413, 2425.
99 See supra notes 8 to 17 and accompanying text.
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given statute is usually unknowable with respect to the precise situation presented to the court.100
Accordingly, purposivists and textualists instead seek to construct an objective intent.101
Purposivists and textualists disagree about the best way to determine this objective intent and
about the focus of the objective construct. Purposivists ask what a reasonable legislator would
have been trying to achieve by enacting the disputed statute,102 while textualists ask what a
reasonable English speaker would convey with the disputed words.103 This disagreement is based
in large part on distinct views of the institutional competence of the courts.104 The concept of
“institutional competence” assumes that each branch of government “has a special competence or
expertise, and the key to good government is not just figuring out what is the best policy, but
figuring out which institutions should be making which decisions and how all the institutions
should interrelate.”105 “[T]he rules of [statutory] interpretation allocate lawmaking power among
the branches of government, and those rules should reflect and respect what, if anything, the
Constitution has to say about that allocation.”106
Consequently, because purposivists and textualists have different views of how judges can best
act to advance the will of the legislature, they advocate different modes of interpretation107 and
may turn to different tools for evidence of Congress’s objective intent.108 Although some jurists
have argued that textualism has “won” the statutory interpretation debate109—Justice Kagan
declared in 2015 that “we’re all textualists now”110—critical distinctions in judges’ interpretive
theories arguably remain, as discussed below.

100 Manning, Inside Congress’s Mind, supra note 31, at 1912–13. See also, e.g., Hand, supra note 51, at 106 (“[Often,
t]he men who used the language did not have any intent at all about the case that has come up; it had not occurred to
their minds. Strictly speaking, it is impossible to know what they would have said about it, if it had.”); Manning,
Without the Pretense of Legislative Intent, supra note 42, at 2406 (“Since Congress is a ‘they,’ not an ‘it,’ . . . such
intent does not exist as a fact in the world, simply waiting to be found.” (quoting Kenneth A. Shepsle, Congress Is a
‘They,’ Not an ‘It’: Legislative Intent as Oxymoron
, 12 INT’L REV. L. & ECON. 239, 239 (1992))).
101 See, e.g., Manning, Inside Congress’s Mind, supra note 31, at 1913–14. Cf. Caleb Nelson, What is Textualism?, 91
VA. L. REV. 347, 348 (2005) (arguing that both theories use evidence of “the subjective intent of the enacting
legislature” to “construct their sense of objective meaning”).
102 See HART & SACKS, supra note 17, at 1148.
103 See Frank H. Easterbrook, The Role of Original Intent in Statutory Construction, 11 HARV. J.L. & PUB. POL’Y 59, 65
(1988); Manning, Textualism and the Equity of the Statute, supra note 32, at 109; Scalia, supra note 84, at 17.
104 E.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 91.
105 William N. Eskridge, Jr. & Philip P. Frickey, An Historical and Critical Introduction to The Legal Process, in HART
& SACKS, supra note 17, at lx.
106 Manning, Without the Pretense of Legislative Intent, supra note 42, at 2413 (describing the concept of institutional
settlement pioneered by Hart & Sacks); see also HART & SACKS, supra note 17, at 4–5 (defining “the principle of
institutional settlement” as expressing “the judgment that decisions which are the duly arrived at result of duly
established procedures . . . ought to be accepted as binding” and arguing that “the effect to be given” to any particular
settlement of a dispute, whether it was decided through a statute or a judicial decision, should be evaluated in light of
the procedure that created that settlement).
107 See Manning, Without the Pretense of Legislative Intent, supra note 42, at 2425–27.
108 See, e.g., Molot, The Rise and Fall of Textualism, supra note 44, at 26.
109 Cf., e.g., Jonathan R. Siegel, The Inexorable Radicalization of Textualism, 158 U. PA. L. REV. 117, 119–20 (2009)
(discussing this idea, but ultimately disagreeing that the two methods have converged).
110 Elena Kagan, The Scalia Lecture: A Dialogue with Justice Kagan on the Reading of Statutes at 8:28 (Nov. 17,
2015), http://today.law.harvard.edu/in-scalia-lecture-kagan-discusses-statutory-interpretation; cf., e.g., Jeffrey A.
Pojanowski, Statutes in Common Law Courts, 91 TEX. L. REV. 479, 480 (2013) (“The dust from the Thirty Years’
statutory interpretation wars may have settled and, while textualism has not won an unconditional surrender in the
Supreme Court, it appears to have gained substantial territory before its truce with purposivism.”); West Virginia v.
EPA, 142 S. Ct. 2587, 2641 (2022) (Kagan, J., dissenting) (saying her prior remarks appeared to be “wrong” and
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Purposivism
Purposivists argue “that legislation is a purposive act, and judges should construe statutes to
execute that legislative purpose.”111 Purposivists often focus on the legislative process, taking into
account the problem that Congress was trying to solve by enacting the disputed law and asking
how the statute accomplished that goal.112 They argue that courts should interpret ambiguous text
“in a way that is faithful to Congress’s purposes.”113 Two preeminent purposivists from the mid-
20th century, Henry Hart and Albert Sacks, advocated the “benevolent presumption . . . that the
legislature is made up of reasonable men pursuing reasonable purposes reasonably.”114 But there
was a caveat to this presumption: it should not hold if “the contrary is made unmistakably to
appear” in the text of the statute.115
Purposivists believe that judges can best observe legislative supremacy by paying attention to the
legislative process.116 The Constitution “charges Congress, the people’s branch of representatives,
with enacting laws,”117 and accordingly, purposivists contend that courts should look to “how
Congress actually works.”118 As such, they argue that to preserve the “integrity of legislation,”
judges should pay attention to “how Congress makes its purposes known, through text and
reliable accompanying materials constituting legislative history.”119 Courts should take into
consideration any “institutional device that facilitates compromise and helps develop the
consensus needed to pass important legislation.”120 As one purposivist judge said, “[w]hen courts
construe statutes in ways that respect what legislators consider their work product, the judiciary

asserting that “[t]he current Court is textualist only when being so suits it”).
111 ROBERT A. KATZMANN, JUDGING STATUTES 31 (2014). Academics sometimes distinguish between “purpose” and
“intent,” most frequently using “purpose” to mean the objective intent that is the goal of new purposivism, and “intent”
to mean the legislature’s actual intent, which was the goal of the old “intentionalism.” See, e.g., Siegel, supra note 109,
at 123–24. However, courts generally use the two words interchangeably, and this report follows suit. See MIKVA &
LANE, supra note 9, at 107; see, e.g., Liparota v. United States, 471 U.S. 419, 424–25 (1985) (referring both to
“congressional intent” and “congressional purpose”).
112 E.g. HART & SACKS, supra note 17, at 1148.
113 KATZMANN, supra note 111, at 31.
114 HART & SACKS, supra note 17, at 1148. See also Breyer, supra note 32, at 854 (“Given this statutory background,
what would a reasonable human being intend this specific language to accomplish?” (internal quotation marks
omitted)).
115 HART & SACKS, supra note 17, at 1125.
116 See Manning, Without the Pretense of Legislative Intent, supra note 42, at 2425, 2426 (describing purposivism as a
belief that “the judiciary respect[s] legislative supremacy by implementing the apparent legislative plan of action,” or
by “supplying sensible means of carrying out legislative policies that Congress cannot possibly spell out completely in
a world of great and ever-changing complexity”). See also, e.g., Rebecca M. Kysar, Interpreting by the Rules, 99 TEX.
L. REV. 1115, 1167 (2021) (exploring “ways in which taking [congressional] procedure seriously” can strengthen a
judge’s role “as a faithful agent of the legislature”).
117 KATZMANN, supra note 111, at 4.
118 Breyer, supra note 32, at 858. As one textbook pithily asks, “Shouldn’t it make a normative difference that a statute
was enacted by legislators seeking to solve a social problem in the face of disagreement, and not by a drunken mob of
legislators with no apparent purpose or who had agreed to adopt any bill chosen by a throw of the dice?” ESKRIDGE ET
AL., supra note 40, at 243.
119 KATZMANN, supra note 111, at 4.
120 Breyer, supra note 32, at 860 (arguing that if legislators knew courts would not consider the legislative history that
legislators considered critical to determining the meaning of a statute, the relevant policymakers “might not have
agreed on the legislation”).
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not only is more likely to reach the correct result, but also promotes comity with the first branch
of government.”121
To discover what a reasonable legislator was trying to achieve,122 purposivists rely on the statute’s
“policy context,” looking for “evidence that goes to the way a reasonable person conversant with
the circumstances underlying enactment would suppress the mischief and advance the remedy.”123
Purposivists are more willing than textualists to consider legislative history.124 Arguably, the core
of purposivism is “reasoning by example” and asking whether various specific applications of the
statute further its general purpose.125 As a result, purposivists maintain that courts should first ask
what problem Congress was trying to solve,126 and then ask whether the suggested interpretation
fits into that purpose.127 Hart and Sacks suggested that judges should seek “to achieve consistency
of solution . . . to make the results in the particular cases respond to . . . some general objective or
purpose to be attributed to the statute.”128 Judges should look for interpretations that promote
“coherence and workability.”129
Detractors argue that it is likely impossible to find one shared intention behind any given piece of
legislation, and that it is inappropriate for judges to endeavor to find legislative purpose.130 Such
critics claim that judges are not well-equipped to understand how complex congressional
processes bear on the law finally enacted by Congress—not least because the records of that
process, in the form of legislative history, are often internally contradictory and otherwise

121 KATZMANN, supra note 111, at 36.
122 See HART & SACKS, supra note 17, at 1148.
123 Manning, What Divides Textualists from Purposivists?, supra note 23, at 91. See also Breyer, supra note 32, at 853–
54 (“Sometimes [a court] can simply look to the surrounding language in the statute or to the entire statutory scheme
and ask, ‘Given this statutory background, what would a reasonable human being intend this specific language to
accomplish?’ Often this question has only one good answer, but sometimes the surrounding statutory language and the
‘reasonable human purpose’ test cannot answer the question. In such situations, legislative history may provide a clear
and helpful resolution.”).
124 See, e.g., Breyer, supra note 32, at 854; KATZMANN, supra note 111, at 35. See also discussion infra “Legislative
History.”

125 See Levi, supra note 39, at 501, 504–05. See also HART & SACKS, supra note 17, at 1119–20, 1378–79; MIKVA &
LANE, supra note 9, at 111. Cf. Richard A. Posner, Statutory Interpretation—in the Classroom and in the Courtroom,
50 U. CHI. L. REV. 800, 817 (1983) (“I suggest that the task for the judge called upon to interpret a statute is best
described as one of imaginative reconstruction. The judge should try to think his way as best he can into the minds of
the enacting legislators and imagine how they would have wanted the statute applied to the case at bar.”). Posner
distinguishes his own suggestion from the approach of Hart and Sacks by arguing the judge should attempt to take into
account the actual compromises struck. Id. at 819–20.
126 See, e.g., United Steelworkers of Am., AFL-CIO-CLC v. Weber, 443 U.S. 193, 201–08 (1979) (evaluating
legislative history to determine “Congress’ primary concern in enacting” the disputed statute and refusing to adopt an
interpretation that would “bring about an end completely at variance with the purpose of the statute” (quoting United
States v. Public Utils. Comm’n, 345 U.S. 295, 315 (1953)) (internal quotation marks omitted)). See also Breyer, supra
note 32, at 864–65 (noting difficulties of ascribing an “intent” to Congress, but concluding that it is possible).
127 See, e.g., Freeman v. Quicken Loans, Inc., 566 U.S. 624, 632 (2012) (noting that a particular interpretation would
undermine the purpose of a statute by imposing liability on “the very class for whose benefit [a particular statute] was
enacted,” “provid[ing] strong indication that something in [that] interpretation is amiss”).
128 HART & SACKS, supra note 17, at 1119.
129 See Breyer, supra note 32, at 847. See also, e.g., Cortez Byrd Chips v. Bill Harbert Constr. Co., 529 U.S. 193, 198–
203 (2000) (concluding that “enlightenment” as to a statute’s meaning would “not come merely from parsing the
language,” and looking to statutory history to avoid a reading that would be “at odds” with the law’s policy and “would
create anomalous results”).
130 See, e.g., Manning, Textualism and Legislative Intent, supra note 16, at 430.
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unreliable.131 Opponents of purposivism also sometimes argue that the theory is too easily
manipulable, allowing the purposivist to ignore the text and “achieve what he believes to be the
provision’s purpose.”132
Textualism
In contrast to purposivists, textualists focus on the words of a statute, emphasizing text over any
unstated purpose.133 Textualists argue courts should “read the words of that [statutory] text as any
ordinary Member of Congress would have read them.”134 They look for the meaning “that a
reasonable person would gather from the text of the law, placed alongside the remainder of the
corpus juris [the body of law].”135 Modern textualists therefore are more focused on how an
ordinary (albeit well-educated) person would read the law, rather than on the legislators who
wrote the law.136 Textualists care about statutory purpose only to the extent that it is evident from
the text.137 Accordingly, textualists “look at the statutory structure and hear the words as they
would sound in the mind of a skilled, objectively reasonable user of words.”138
Textualists believe that “judges best respect[] legislative supremacy” when they follow rules that
prioritize the statutory text.139 For textualists, focusing on the text alone and adopting the
“presumption that Congress ‘means . . . what it says’ enables Congress to draw its lines reliably—
without risking that a court will treat an awkward, strange, behind-the-scenes compromise as a
legislative error or oversight.”140 As Judge Frank Easterbrook stated, “[s]tatutes are not exercises
in private language,” but are “public documents, negotiated and approved by many parties.”141
Textualism focuses on the words of a statute because it is that text that survived these political
processes and was duly enacted by Congress, exercising its constitutional power to legislate.142

131 See, e.g., SCALIA & GARNER, supra note 24, at 20–21, 376–78. But see, e.g., Brett M. Kavanaugh, Fixing Statutory
Interpretation
, 129 HARV. L. REV. 2118, 2122 (2016) (reviewing KATZMANN, supra note 111) (agreeing, as textualist
judge, that it is important for judges to understand the legislative process).
132 SCALIA & GARNER, supra note 24, at 18.
133 E.g., George H. Taylor, Structural Textualism, 75 B.U. L. REV. 321, 327 (1995). See also, e.g., King v. Burwell, 576
U.S. 473, 486 (2015) (“If the statutory language is plain, we must enforce it according to its terms.”); Freeman v.
Quicken Loans, Inc., 566 U.S. 624, 637 (2012) (“Vague notions of statutory purpose provide no warrant for expanding
[the disputed statutory] prohibition beyond the field to which it is unambiguously limited . . . .”).
134 Chisom v. Roemer, 501 U.S. 380, 405 (1991) (Scalia, J., dissenting).
135 Scalia, supra note 84, at 17.
136 See, e.g., Amy Coney Barrett, Congressional Insiders and Outsiders, 84 U. CHI. L. REV. 2193, 2194 (2017).
137 E.g. SCALIA & GARNER, supra note 24, at 33.
138 Easterbrook, The Role of Original Intent in Statutory Construction, supra note 103, at 65. Cf. Holmes, supra note
67, at 417–18 (“[W]e ask, not what this man meant, but what those words would mean in the mouth of a normal
speaker of English, using them in the circumstances in which they were used, and it is to the end of answering this last
question that we let in evidence as to what the circumstances were.”).
139 See Manning, Without the Pretense of Legislative Intent, supra note 42, at 2426–27.
140 Id. at 2427 (emphasis omitted) (quoting Conn. Nat’l Bank v. Germain, 503 U.S. 249, 254 (1992)). See also SCALIA
& GARNER, supra note 24, at 39 (arguing legal instruments should not always be construed to make sense because
“often,” imperfect legal drafting “is the consequence of a compromise that it is not the function of the courts to upset”).
141 Easterbrook, The Role of Original Intent in Statutory Construction, supra note 103, at 60.
142 See, e.g., Scalia, supra note 84, at 17 (“[I]t is simply incompatible with democratic government, or indeed, even
with fair government, to have the meaning of a law determined by what the lawgiver meant, rather than by what the
lawgiver promulgated.”). See also Manning, Textualism and Legislative Intent, supra note 16, at 445 (“[F]or textualists,
any attempt to overlay coherence on a statutory text that otherwise seems to have problems of fit unacceptably
threatens to undermine the bargaining process that produced it.”).
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Textualists have argued that focusing on “genuine but unexpressed legislative intent” invites the
danger that judges “will in fact pursue their own objectives and desires”143 and, accordingly,
encroach into the legislative function by making, rather than interpreting, statutory law.144
To discover what a reasonable English-speaker would think a statute’s text means, textualists look
for evidence of the statute’s “semantic context,” seeking “evidence about the way a reasonable
person conversant with relevant social and linguistic practices would have used the words.”145
Many textualists decline to use legislative history under most circumstances.146 Instead, textualist
judges generally seek to discover “the shared conventions” that are inherent in the statutory
language,147 asking what “assumptions [were] shared by the speakers and the intended
audience.”148 As evidence of these shared assumptions, textualists might turn to rules of grammar,
or to the so-called “canons of construction” that “reflect broader conventions of language use,
common in society at large at the time the statute was enacted.”149
Critics of textualism argue that the theory is an overly formalistic approach to determining the
meaning of statutory text that ignores the fact that courts have been delegated interpretive
authority under the Constitution.150 Critics further claim that the theory of legislative supremacy
requires courts to seek the meaning that Congress intended to convey.151 Opponents of textualism
sometimes claim that Congress legislates with this background understanding, expecting courts to
pay attention to legislative processes and the law’s purpose when applying it to specific
circumstances.152 As a result, textualism’s detractors argue that considering evidence of a statute’s
purpose can be more constraining on a judge than merely considering the text, divorced from
evidence of legislative intent.153

143 Scalia, supra note 84, at 17–18. See also Molot, The Rise and Fall of Textualism, supra note 44, at 25–26
(examining parallels between textualism and legal realism).
144 See, e.g., Easterbrook, supra note 138, at 62 (“The use of original intent rather than an objective inquiry into the
reasonable import of the language permits a series of moves. Each move greatly increases the discretion, and therefore
the power, of the court.”).
145 Manning, What Divides Textualists from Purposivists?, supra note 23, at 91. See also SCALIA & GARNER, supra note
24, at 33 (endorsing the “fair reading” method of statutory interpretation, which gathers purpose “only from the text
itself, consistently with the other aspects of its context,” and defining this context to include “textual purpose” along
with “(1) a word’s historical associations acquired from recurrent patterns of past usage, and (2) a word’s immediate
syntactic setting—that is, the words that surround it in a specific utterance”). Cf. Frankfurter, supra note 8, at 533
(“And so the bottom problem is: What is below the surface of the words and yet fairly a part of them?”).
146 E.g., Manning, Textualism and Legislative Intent, supra note 16, at 420. But see, e.g., Frank H. Easterbrook, What
Does Legislative History Tell Us?
, 66 CHI.-KENT L. REV. 441, 444 (1990) (“No degree of skepticism concerning the
value of legislative history allows us to escape its use. Especially not when we know that laws have no ‘spirit,’ that
they are complex compromises with limits and often with conflicting provisions, the proponents of which have
discordant understandings. Legislative history shows the extent of agreement.”). For an explanation of when textualists
might employ legislative history, see infra “Purposes for Using Legislative History.”
147 Manning, Textualism and Legislative Intent, supra note 16, at 433.
148 Easterbrook, What Does Legislative History Tell Us?, supra note 146, at 443.
149 Nelson, supra note 101, at 383.
150 See, e.g., supra note 87 and accompanying text.
151 See, e.g., Mark Seidenfeld, Textualism’s Theoretical Bankruptcy and its Implication for Statutory Interpretation,
100 B.U. L. REV. 1817, 1822 (2020).
152 See, e.g., KATZMANN, supra note 111, at 47–48.
153 See, e.g., id. at 48; Seidenfeld, supra note 151, at 1841–43.
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Purposivism vs. Textualism In Practice
A Clear Distinction
The distinctions between these two theories were illustrated in the Supreme Court case of
Arlington Central School District Board of Education v. Murphy.154 The case arose out of a suit in
which a student’s parents had successfully sued a school district under the Individuals with
Disabilities Education Act.155 As relevant to the case, that Act provided that “a court ‘may award
reasonable attorneys’ fees as part of the costs’ to parents who prevail in an action brought under
the Act.”156 The parents sought to recover fees paid to an expert who had provided assistance
throughout the proceedings.157 The issue before the Court was whether the Act “authorized the
compensation of expert fees.”158
In a textualist opinion written by Justice Alito, the majority of the Court concluded that the Act
did not authorize the compensation of expert fees.159 Emphasizing that courts must “begin with
the text” and “enforce [that text] according to its terms,”160 the Court stated that the provision
“provides for an award of ‘reasonable attorneys’ fees,’” without “even hint[ing]” that the award
should also include expert fees.161 The majority opinion rejected the parents’ arguments that
awarding expert fees would be consistent with the statute’s goals and its legislative history, “in
the face of the [Act’s] unambiguous text.”162
By contrast, Justice Breyer’s dissenting opinion embodied a purposivist approach to interpreting
the statute.163 He concluded that the disputed term “costs” should be interpreted “to include the
award of expert fees” for two reasons: “First, that is what Congress said it intended by the phrase.
Second, that interpretation furthers the [Act’s] statutorily defined purposes.”164 Justice Breyer
relied on the bill’s legislative history and the Act’s “basic purpose”—to guarantee that children
with disabilities receive quality public education—as primary evidence of the statute’s
meaning.165 He did not agree that the statute’s text was unambiguous.166 Although he expressed
that a literal reading of the provision would not authorize the costs sought by the parents, he
concluded that this reading was “not inevitable.”167 Instead, he believed that his reading, “while
linguistically the less natural, is legislatively the more likely.”168

154 Arlington Cent. Sch. Dist. Bd. of Educ. v. Murphy, 548 U.S. 291 (2006).
155 Id. at 294.
156 Id. at 293 (quoting 20 U.S.C. § 1415(i)(3)(B)).
157 Id. at 294.
158 Id. at 295 (emphasis added).
159 See id. at 298.
160 Id. at 296 (quoting Hartford Underwriters Ins. Co. v. Union Planters Bank, N.A., 530 U.S. 1, 6 (2000) (internal
quotation mark omitted).
161 Id. at 297 (quoting 20 U.S.C. § 1415(i)(3)(B)).
162 Id. at 303–04.
163 See id. at 309 (Breyer, J., dissenting).
164 Id.
165 Id. at 312–13.
166 Id. at 318.
167 Id. at 319.
168 Id.
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A Convergence of Theories?
Many judges, however, do not necessarily identify as pure purposivists or textualists; or even if
they do, in practice, they will often employ some elements from each theory.169 Some scholars
have argued that even the theoretical gap between these two theories is narrowing.170 Most
modern purposivists consider the statutory text to be both a starting point171 and an ultimate
constraint.172 Given the broad consensus that a statute’s text is primary, some have asserted that
textualism has prevailed over purposivism.173 Nonetheless, most textualists will look past the
plain text, standing alone, to discover the relevant context and determine what problem Congress
was trying to address.174 Courts accordingly continue to disagree about what types of context are
fairly deemed inherent in that text175 and about which interpretive tools may help discover the
context that is necessary to understand the statute’s meaning.176
One Supreme Court case issued in 2017 demonstrates the increasing similarities between the two
factions, as well as the remaining distinctions. In NLRB v. SW General, Inc., the Supreme Court
considered whether the service of the Acting General Counsel of the National Labor Relations
Board violated a statute that limits the ability of federal employees to serve as “acting officers.”177
The majority and dissenting opinions both began their analysis of the statute with its text before

169 See Abbe R. Gluck & Richard A. Posner, Statutory Interpretation on the Bench: A Survey of Forty-Two Judges on
the Federal Courts of Appeals
, 131 HARV. L. REV. 1298, 1302 (2018) (describing predominant approach among federal
appellate judges as “intentional eclecticism”). See also William N. Eskridge, Jr., & Philip P. Frickey, Statutory
Interpretation as Practical Reasoning
, 42 STAN. L. REV. 321, 321–22 (1990) (“Many commentators argue that judicial
interpretation is, or at least ought to be, inspired by grand theory. We think these commentators are wrong, both
descriptively and normatively: Judges’ approaches to statutory interpretation are generally eclectic, not inspired by any
grand theory, and this is a good methodology.”).
170 See Molot, The Rise and Fall of Textualism, supra note 44, at 3 (“Given that nonadherents and adherents of
textualism alike place great weight on statutory text and look beyond text to context, it is hard to tell what remains of
the textualism-purposivism debate.”); Nelson, supra note 101, at 348 (“[J]udges whom we think of as textualists
construct their sense of objective meaning from what the evidence that they are willing to consider tells them about the
subjective intent of the enacting legislature. Many textualists do impose more restrictions than the typical intentionalist
on the evidence of intent that they are willing to consider, but those restrictions need not reflect any fundamental
disagreement about the goals of interpretation.”); Lawrence M. Solan, The New Textualists’ New Text, 38 LOY. L.A. L.
REV. 2027, 2028 (2005) (“Gone largely unnoticed in the battles between these camps during the past quarter century is
the fact that both sides in the debate agree upon almost everything when it comes to statutory interpretation.”).
171 See, e.g., KATZMANN, supra note 111, at 4.
172 See, e.g., HART & SACKS, supra note 17, at 1374 (arguing judges should not give the words of a statute either “a
meaning they will not bear, or . . . a meaning which would violate any established policy of clear statement”); id. at
1375 (noting words “limit[] the particular meanings that can properly be attributed” to the statute).
173 See, e.g., Jimmy Hoover, Justice Breyer’s Statutory Interpretation Swan Song?, LAW360 (Apr. 4, 2022),
https://www.law360.com/publicpolicy/articles/1480811/justice-breyer-s-statutory-interpretation-swan-song-
?nl_pk=77a8fbcd-0ce9-4d0f-a0ac-3a4c7fd100a8.
174 See, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 84 (“Because speakers use
language purposively, textualists recognize that the relevant context for a statutory text includes the mischiefs the
authors were addressing.”). See also, e.g., McGirt v. Oklahoma, 140 S. Ct. 2452, 2464 (2020) (Gorsuch, J.,) (referring
to “Congress’s expressed policy” apparently obvious from the text of the statute).
175 See, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 91. Cf. Frankfurter, supra note 8,
at 533 (“And so the bottom problem is: What is below the surface of the words and yet fairly a part of them?”).
176 See, e.g., John F. Manning, Legal Realism & the Canons’ Revival, 5 GREEN BAG 2d 283, 285 (2002).
177 NLRB v. SW Gen., Inc., 137 S. Ct. 929, 935 (2017). For more discussion of the substance of this case, see CRS
Legal Sidebar WSLG1840, Help Wanted: Supreme Court Holds Vacancies Act Prohibits Nominees from Serving as
Acting Officers
, by Valerie C. Brannon.
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proceeding to consider many of the same sources to determine the meaning of the disputed
statute.178
The majority opinion in SW General, authored by Chief Justice John Roberts, principally
represented a textualist point of view, although it also included some elements of purposivism.179
In describing the facts of the case, the Chief Justice began with an explanation of the problem that
Congress faced when it first enacted the disputed statute, and, in so doing, considered the original
version of that statute and subsequent amendments intended to address continuing disputes over
the ability of federal employees to serve as acting officers.180 The Court’s analysis started with the
statutory text, considering its meaning by looking to the ordinary meaning of the words, rules of
grammar, and statutory context.181 The Court emphasized two “key words” in the disputed
provision.182 The majority then noted that it did not need to consider the “extra-textual evidence”
of “legislative history, purpose, and post-enactment practice” because the text was clear.183
Nonetheless, the Court went on to evaluate and reject this evidence as “not compelling.”184
Ultimately, the majority held that the acting officer’s service violated the relevant statute.185
In dissent in SW General, Justice Sonia Sotomayor concluded that the “text, purpose, and history”
of the statute suggested the opposite conclusion.186 Like the majority opinion, the dissent began
by considering the meaning of the text, and acknowledged that “taken in isolation,” certain words
could support the majority’s reading.187 However, Justice Sotomayor concluded that two textual
canons of construction implied that the statute should be read differently in light of the full
statutory context.188 Additionally, while the dissenting opinion similarly considered “the events
leading up to” the enactment of the relevant statute, Justice Sotomayor also placed some weight
on the historical practice of the executive department after the passage of the statute.189 The
dissent used the provision’s legislative history to inform its understanding of the historical
practice under the statute, in its earlier and current forms, and reached a different conclusion from
the majority opinion.190 As a result, the dissent represents a more purposivist view of the case, but
one that still concentrated on the statutory text.191
As SW General illustrates, the particular tools a judge uses to discover evidence about the
meaning of the statute, and the weight that the judge gives to that evidence, can influence the
outcome of a case.192 In contrast to the opinions of Justices Alito and Breyer in Arlington Central

178 See SW Gen., Inc., 137 S. Ct. at 938; id. at 950 (Sotomayor, J., dissenting).
179 See The Supreme Court 2016 Term: Leading Case: NLRB v. SW General, Inc., 131 HARV. L. REV. 353, 353 (2017)
(“[T]he Court relied on the ordinary meaning of the provision’s text over and against arguments from purpose, post-
enactment practice, and even a semantic canon.”).
180 SW Gen., Inc., 137 S. Ct. at 935–36 (majority opinion).
181 Id. at 938–39.
182 Id. at 938.
183 Id. at 941–42.
184 Id. at 942.
185 Id. at 944.
186 Id. at 950 (Sotomayor, J., dissenting).
187 See id. at 950.
188 Id. at 950–52.
189 Id. at 953–54.
190 See id.
191 See id. at 950.
192 Compare id. at 938, 942 (majority opinion) (focusing primarily on two “key words” and rejecting “extra-textual
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School District,193 the two opinions in SW General considered many of the same interpretive
tools, and the text of the statute was central to both opinions.194 However, like the textualist
majority opinion in Arlington Central School District,195 the textualist majority opinion in SW
General
explained that legislative history is disfavored where the text is clear,196 giving less
weight to this tool than the dissenting opinion.197 These cases demonstrate that if a judge’s theory
of statutory interpretation counsels that some tools should be preferred over others,198 that theory
can change the way the judge resolves a particular dispute. A number of scholars have
nonetheless argued that the divide between purposivism and textualism may not be so stark, in
that the choice to use legislative history or the canons of construction may not always neatly track
judges’ legal philosophies.199
Empiricism and Refinement of the Theories
In theory, both purposivism and textualism seek the most objectively reasonable meaning of a
statute, looking to the construct of an objective intent rather than attempting to discern Congress’s
actual intent with respect to the question before the court.200 As two scholars argued in a 2017
article, the legal system often purposefully seeks “to replace real answers with fake ones.”201 In
this view, persistent disagreements about “real” answers such as actual legislative intent require
the legal system to “helpfully” substitute “fake” answers “on which society (mostly) agrees.”202
Objective intent qualifies as one of these “fake” answers, although as previously discussed,
purposivists and textualists continue to disagree on the focus of objective intent. Accordingly,
judges subscribing to these theories have justified their rulings by reference to specific, accepted
tools of statutory interpretation that they claim helped constrain judges to appropriately defined
legislative intent.203
Because the objective intent sought by both purposivists and textualists is a construct, it is open to
attack on the basis that it does not reflect actual meaning. Some legal scholars have conducted
empirical research to examine additional means of identifying intent and legal meaning.204

evidence”); with id. at 954 (Sotomayor, J., dissenting) (arguing the majority’s position “disregards the full text of the
[relevant act] and finds no support in its purpose or history”) (emphasis added).
193 Arlington Cent. Sch. Dist. Bd. of Educ. v. Murphy, 548 U.S. 291 (2006); see supra “A Clear Distinction.”
194 See SW Gen., Inc., 137 S. Ct. at 938 (majority opinion); id. at 950 (Sotomayor, J., dissenting).
195 548 U.S. at 304 (“Under these circumstances, where everything other than the legislative history overwhelmingly
suggests that expert fees may not be recovered, the legislative history is simply not enough.”).
196 SW Gen., Inc., 137 S. Ct. at 942 (“The text is clear, so we need not consider this extra-textual evidence.”).
197 See id. at 953 (Sotomayor, J., dissenting).
198 See, e.g., Molot, The Rise and Fall of Textualism, supra note 44, at 3–4 (noting differences in types of “context”
considered by textualists and purposivists).
199 See, e.g., Gluck & Posner, supra note 169, at 1310–11; Anita S. Krishnakumar, Reconsidering Substantive Canons,
84 U. CHI. L. REV. 825, 891 (2017); John F. Manning, The New Purposivism, 2011 SUP. CT. REV. 113, 146–47 (2011);
Nina Mendelson, Change, Creation, and Unpredictability in Statutory Interpretation: Interpretive Canon Use in the
Roberts Court’s First Decade
, 117 MICH. L. REV. 71, 100 (2018).
200 See, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 91. See also discussion supra
“Major Theories of Statutory Interpretation.”
201 Baude & Sachs, supra note 33, at 1096.
202 Id.
203 Supra “20th Century: Rise of Legal Realism” and “Modern Jurisprudence: Responding to Legal Realism.”
204 See, e.g., Abbe R. Gluck & Lisa Schultz Bressman, Statutory Interpretation from the Inside—An Empirical Study of
Congressional Drafting, Delegation, and the Canons: Part I
, 65 STAN. L. REV. 901, 907 (2013); Stephen C. Mouritsen,
Hard Cases and Hard Data: Assessing Corpus Linguistics as an Empirical Path to Plain Meaning, 13 COLUM. SCI. &
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Scholars assessing tools of statutory interpretation have attempted to discern, for example,
whether judges’ conceptions of ordinary meaning in fact align with how people usually use
language and whether judges’ use of legislative history reflects a proper understanding of how a
bill is passed.
Thus, for example, purposivists seek to ascribe legal meaning to texts, in part, by drawing on the
legislative context in which statutes were enacted. To discover this context, they may look to
legislative history such as committee reports but may also rely on other traditional tools of
interpretation. As discussed in more detail below, some scholars have looked to evidence about
how Congress actually operates in order to criticize—or support—existing uses of legislative
history and the canons of construction.205 This scholarship, once termed “process-based theories”
by Justice Amy Coney Barrett, seems to draw from purposivism while also challenging some
judges’ use of particular tools.206
In comparison, textualists seek to determine the most objectively reasonable meaning of the
words of a statute by asking how a reasonable English speaker would understand what is being
conveyed. Some scholars have used empirical research to evaluate textualism’s assumptions
about how people ordinarily use language, suggesting refinements in the tools used to assess
ordinary meaning as well as the canons of construction.207
It remains to be seen how useful judges who focus on objective intent will consider tools that
arguably go to actual meaning.208 Nonetheless, as discussed below, a number of judges have cited
empirical studies to refine their statutory analyses, either to replace or supplement their traditional
methods of discerning legislative intent. Further, at least one scholar has stated that some sources
described as empirical in nature are still filtered through statutory context and legal interpretation,
preventing those sources “from transforming legal interpretation into an empirical science.”209
Tools of Statutory Interpretation
Judges use a variety of tools to help them interpret statutes, most frequently relying on five types
of interpretive tools: ordinary meaning, statutory context, canons of construction, legislative
history, and evidence of the way a statute is implemented.210

TECH. L. REV. 156, 164 (2011).
205 See, e.g., Jesse M. Cross, Legislative History in the Modern Congress, 57 HARV. J. ON LEGIS. 91, 95 (2020); Gluck
& Bressman, supra note 204, at 905.
206 Barrett, supra note 136, at 2194.
207 See, e.g., Mouritsen, Hard Cases and Hard Data, supra note 204, at 164; Kevin Tobia, Brian G. Slocum & Victoria
Nourse, Statutory Interpretation from the Outside, 122 COLUM. L. REV. 213, 221–23 (2022).
208 See, e.g., Carissa Byrne Hessick, Corpus Linguistics and the Criminal Law, 2017 B.Y.U. L. REV. 1503, 1511 (2017)
(arguing relying on a judge’s intuition about a word’s ordinary meaning is more appropriate than the frequency analysis
involved in consulting corpus linguistics); Manning, Inside Congress’s Mind, supra note 31, at 1916 (arguing that
studies about legislative drafting practices do not undermine “the intent skepticism that has framed so much of the
discussion about how to read statutes”).
209 Brian G. Slocum, Big Data and Accuracy in Statutory Interpretation, 86 BROOKLYN L. REV. 357, 361 (2021).
210 In addition to the tools discussed below, courts also rely on judicial precedent; that is, if another case has previously
interpreted a particular statutory provision, a judge may afford that prior interpretation some significance. See, e.g.,
Krishnakumar, Reconsidering Substantive Canons, supra note 199, at 887 (“Supreme Court precedent and practical
consequences . . . stand out as the two most frequently referenced alternate interpretive resources [in Supreme Court
opinions decided between 2006 and 2012, other than text or plain meaning].”). However, this process of reasoning is
more or less similar to the way courts normally resolve cases. This report focuses on judicial tools specifically used to
interpret statutes, and accordingly, does not discuss this use of judicial precedent. Nonetheless, it is important to note
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These tools often overlap. For example, a judge might use evidence of an agency’s
implementation of a statute to support her own understanding of a word’s ordinary meaning.211
Further, basic principles about understanding statutory context are sometimes described as canons
of construction.212
Some theories of statutory interpretation counsel that certain tools are generally disfavored; for
example, textualism teaches that judges should only rarely look to legislative history.213
Consequently, a judge’s interpretive theory might influence which tools she uses. Different
judges, then, might unearth different evidence about the meaning of a particular statute,214 and
even if they find the same evidence, they might consider it in different ways.215 However, in
practice, judges will often draw on whatever tools provide useful evidence of the meaning of the
statute before them.
Ordinary Meaning
Courts often begin by looking for the “ordinary” or “plain” meaning of the statutory text.216
Where a term is not expressly defined in the statute,217 courts generally assume “that Congress
uses common words in their popular meaning, as used in the common speech of men.”218 Thus,
for example, in the context of a case that raised the question of what it meant to “use” a gun,
Justice Scalia stated the following in a dissenting opinion:
To use an instrumentality ordinarily means to use it for its intended purpose. When
someone asks, “Do you use a cane?,” he is not inquiring whether you have your
grandfather’s silver-handled walking stick on display in the hall; he wants to know whether

that judges sometimes adopt a “super-strong presumption of correctness for statutory precedents,” meaning that they
will be even more likely to adhere to a prior decision about statutory meaning than they would in any other decisional
context. ESKRIDGE, supra note 87, at 253. See, e.g., Ill. Brick Co. v. Illinois, 431 U.S. 720, 737 (1977)
(“[C]onsiderations of stare decisis weigh heavily in the area of statutory construction, where Congress is free to change
this Court’s interpretation of its legislation.”).
211 See, e.g., S.D. Warren Co. v. Me. Bd. Of Envtl. Prot., 547 U.S. 370, 378 (2006).
212 See, e.g., SCALIA & GARNER, supra note 24, at 167 (describing the “whole-text canon”).
213 See, e.g., Solan, supra note 170, at 2029.
214 See generally, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 91 (describing
distinctions between contextual evidence used by textualists and purposivists).
215 See Anita S. Krishnakumar, Dueling Canons, 65 DUKE L.J. 909, 930–31 (2016) (discussing instances in which
majority and dissenting opinions in Supreme Court cases used “dueling canons” or invoked the same interpretive tools
to support competing statutory constructions).
216 See, e.g., Anita S. Krishnakumar, Statutory Interpretation in the Roberts Court’s First Era: An Empirical and
Doctrinal Analysis
, 62 HASTINGS L.J. 221, 251 (2010) (noting that between January 31, 2006, and June 29, 2009, the
majority of Supreme Court Justices “referenced text/plain meaning and Supreme Court precedent more frequently than
any of the other interpretive tools”). Scholars sometimes use “plain meaning” to refer to the “literalist” school of
statutory interpretation, supra note 51, and use “ordinary meaning” to refer to the concept invoked by modern
textualists. See, e.g., Richard H. Fallon, Jr., Three Symmetries between Textualist and Purposivist Theories of Statutory
Interpretation—and the Irreducible Roles of Values and Judgment within Both
, 99 CORNELL L. REV. 685, 687 (2014).
This report does not make this distinction, focusing primarily on modern invocations of the concept by courts, which do
not generally distinguish the terms in this way. See Mouritsen, Hard Cases and Hard Data, supra note 204, at 164.
217 Stenberg v. Carhart, 530 U.S. 914, 942 (2000) (“When a statute includes an explicit definition, we must follow that
definition, even if it varies from that term’s ordinary meaning.”).
218 Frankfurter, supra note 8, at 536. See also, e.g., Wooden v. United States, 142 S. Ct. 1063, 1069 (2022) (interpreting
a statutory term in a criminal law by “consider[ing] first first how an ordinary person (a reporter; a police officer; yes,
even a lawyer) might describe” the defendant’s crimes).
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you walk with a cane. Similarly, to speak of “using a firearm” is to speak of using it for its
distinctive purpose, i.e., as a weapon.219
The Supreme Court has also referred to this exercise as seeking a word’s “natural meaning”220 or
its “normal and customary meaning.”221 However, this “ordinary meaning” presumption can be
overcome if there is evidence that the statutory term is a term of art that has a specialized
meaning in law222 or in another relevant field.223 In addition, a word’s ordinary meaning may
change over time. In that situation, the Court will either effectuate the meaning of the term at the
time of the statute’s enactment224 or, depending on the statutory context and relevant history,
conclude that new applications are covered by the plain text.225
Judges may use a wide variety of materials to gather evidence of a text’s ordinary meaning. In
many cases, “simple introspection” suffices, as judges are English speakers who presumably
engage in everyday conversation like the rest of the general public.226 Judges also turn to
dictionaries to help inform their understanding of a word’s normal usage.227 Judges may then
have to choose between multiple definitions provided by the same dictionary228 or by different
dictionaries.229 Courts have also turned to books to discover a word’s ordinary meaning, drawing
from works such as Moby Dick or the Bible230 as well as Aesop’s Fables231 and the work of Dr.
Seuss.232 Judges may also look for evidence of normal usage elsewhere in the law, such as in

219 Smith v. United States, 508 U.S. 223, 242 (1993) (Scalia, J., dissenting).
220 Id. at 228 (majority opinion).
221 Schwegmann Bros. v. Calvert Distillers Corp., 341 U.S. 384, 388 (1951).
222 E.g., FAA v. Cooper, 566 U.S. 284, 291–92 (2012) (concluding that “‘actual damages’ is a legal term of art”).
223 E.g., Van Buren v. United States, 141 S. Ct. 1648, 1657 (2021) (concluding that the statutory term “access” has a
long-standing technical meaning “[i]n the computing context”).
224 E.g., MCI Telecomms. Corp. v. AT&T Co., 512 U.S. 218, 228 (1994). Cf., e.g., Intel Corp. Inv. Policy Comm. v.
Sulyma, 140 S. Ct. 768, 776 (2020) (looking to dictionaries from the time of a statute’s enactment and modern
dictionaries to determine that statutory terms had the same meaning in both time periods).
225 E.g., Bostock v. Clayton Cty., 140 S. Ct. 1731, 1750 (2020).
226 Solan, supra note 170, at 2054. See, e.g., FCC v. AT&T Inc., 562 U.S. 397, 403 (2011) (“‘Personal’ ordinarily
refers to individuals [and not to artificial entities]. . . . Certainly, if the chief executive officer of a corporation
approached the chief financial officer and said, ‘I have something personal to tell you,’ we would not assume the CEO
was about to discuss company business.”).
227 See Solan, supra note 170, at 2055; e.g., Republic of Sudan v. Harrison, 139 S. Ct. 1048, 1056 (2019). Cf. HART &
SACKS, supra note 17, at 1190 (“A dictionary, it is vital to observe, never says what meaning a word must bear in a
particular context. . . . An unabridged dictionary is simply an historical record, not necessarily all-inclusive, of the
meanings which words in fact have borne, in the judgment of the editors, in the writings of reputable authors.”).
228 See, e.g., Muscarello v. United States, 524 U.S. 125, 128 (1998) (emphasizing first dictionary definition as
supplying “the word’s primary meaning”). But see James J. Brudney & Lawrence Baum, Oasis or Mirage: The
Supreme Court’s Thirst for Dictionaries in the Rehnquist and Roberts Eras
, 55 WM. & MARY L. REV. 483, 514 (2013)
(noting many dictionaries use different principles other than frequency of use to order definitions).
229 See, e.g., MCI Telecomms. Corp. v. AT&T Co., 512 U.S. 218, 227 (1994) (rejecting definition that was not only
contained in only one of the dictionaries consulted but also “contradict[ed] one of the meanings contained in virtually
all other dictionaries”). See generally Antonin Scalia & Bryan A. Garner, A Note on the Use of Dictionaries, 16 GREEN
BAG 2d 419 (2013).
230 Muscarello, 524 U.S. at 129.
231 Freeman v. Quicken Loans, Inc., 566 U.S. 624, 634 (2012).
232 Yates v. United States, 574 U.S. 528, 553 (2015) (Kagan, J., dissenting).
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judicial decisions233 or in other governmental materials.234 More recently, some scholars and
judges have turned to corpus linguistics as a source of concrete empirical data for determining the
most common meanings of statutory phrases.235 “Corpus linguistics” uses large “collections of
naturally occurring language called corpora,” for example, such as a database of newspapers, to
study “language function and use.”236
The idea that courts should generally give the words of a statute their “usual” meaning is an old
one.237 This principle straddles judicial philosophies: for example, all current members of the
Supreme Court have invoked this rule of ordinary meaning.238 If Congress does in fact generally
use words as they would be normally understood, this interpretive tool helps judges act as faithful
agents of Congress by ensuring that judges and Congress—along with the ordinary people
governed by statutes—are looking to the same interpretive context: “normal conversation.”239
Although there is wide judicial consensus on the general validity of this rule, disputes arise in its
application. To say that a statutory word should be given the same meaning that it would have in
“everyday language”240 serves only as a starting point for debate in many cases.241 The ordinary

233 E.g., Wooden v. United States, 142 S. Ct. 1063, 1070 (2022); S.D. Warren Co. v. Me. Bd. Of Envtl. Prot., 547 U.S.
370, 376 (2006).
234 E.g., Smith v. United States, 508 U.S. 223, 243 (1993) (Scalia, J., dissenting) (“The normal usage is reflected, for
example, in the United States Sentencing Guidelines . . . .”).
235 See, e.g. Muscarello, 524 U.S. at 129 (looking to a database of newspapers for evidence that a particular statutory
phrase had been used to convey a certain meaning); Caesars Entm’t Corp. v. Int’l Union of Operating Eng’rs Local 68
Pension Fund, 932 F.3d 91, 95 (3d Cir. 2019) (looking to the Corpus of Historical American English to help determine
a statutory term’s most common usage); United States v. Woodson, 960 F.3d 852, 855 (6th Cir. 2020) (looking to the
Corpus of Contemporary American English for evidence of how a word “is used in ordinary speech”); see generally,
e.g.
, Stefan Gries & Brian G. Slocum, Ordinary Meaning and Corpus Linguistics, 2017 B.Y.U. L. REV. 1417 (2017);
Thomas R. Lee & Stephen C. Mouritsen, Judging Ordinary Meaning, 127 YALE L.J. 788 (2018).
236 Mouritsen, Hard Cases and Hard Data, supra note 204, at 159.
237 1 WILLIAM BLACKSTONE, COMMENTARIES *59 (“Words are generally to be understood in their usual and most
known signification, not so much regarding the propriety of grammar as their general and popular use.”).
238 E.g., FCC v. AT&T Inc., 562 U.S. 397, 403 (2011) (Roberts, C.J.) (“When a statute does not define a term, we
typically give the phrase its ordinary meaning.” (internal quotation marks omitted)); FDIC v. Meyer, 510 U.S. 471, 476
(1994) (Thomas, J.) (“In the absence of such a [statutory] definition, we construe a statutory term in accordance with its
ordinary or natural meaning.”); BP Am. Prod. Co. v. Burton, 549 U.S. 84, 91 (2006) (Alito, J.) (“Unless otherwise
defined, statutory terms are generally interpreted in accordance with their ordinary meaning.”); Sebelius v. Cloer, 569
U.S. 369, 376 (2013) (Sotomayor, J.) (“As in any statutory construction case, we start, of course, with the statutory text,
and proceed from the understanding that unless otherwise defined, statutory terms are generally interpreted in
accordance with their ordinary meaning.” (internal quotation marks, alterations, and citations omitted)); Fry v.
Napoleon Cmty. Sch., 137 S. Ct. 743, 753 (2017) (Kagan, J.) (beginning statutory analysis by looking to text’s
“ordinary meaning”); Henson v. Santander Consumer USA Inc., 137 S. Ct. 1718, 1723 (2017) (Gorsuch, J.) (referring
to a word’s meaning “as a matter of ordinary English”); Quarles v. United States, 139 S. Ct. 1872, 1877 (2019)
(Kavanaugh, J.) (referring to a statutory term’s “ordinary usage”); Babcock v. Kijakazi, 142 S. Ct. 641, 645 (2022)
(Barrett, J.) (attempting to discover statute’s “plain meaning”); Delaware v. Pennsylvania, No. 145, Orig., slip op. at 10
(U.S. Feb. 28, 2023) (Jackson, J.) (looking to a statutory term’s “‘ordinary, contemporary, common meaning’” (quoting
Sandifer v. U.S. Steel Corp., 571 U.S. 220, 227 (2014))).
239 Green v. Bock Laundry Mach. Co., 490 U.S. 504, 529 (1989) (Scalia, J., concurring). Cf. Frederick Schauer,
Statutory Construction and the Coordinating Function of Plain Meaning, 1990 SUP. CT. REV. 231, 232 (1990) (arguing
plain language serves “as a second-best coordinating device for multiple decisionmakers attempting to reach some
methodological consensus in the face of substantive disagreements among them”).
240 Yates v. United States, 574 U.S. 528, 553 (2015) (Kagan, J., dissenting).
241 Compare, e.g., Bostock v. Clayton Cty., 140 S. Ct. 1731, 1741 (2020) (giving effect to the “the ordinary public
meaning of the statute’s language at the time of the law’s adoption”), with, e.g., id. at 1824, 1833 (Kavanaugh, J.,
dissenting) (accusing the majority of giving effect to the law’s “literal meaning rather than ordinary meaning”). See
also, e.g.
, Taylor, supra note 133, at 360 (“[S]tructural textualism does not derive meaning simply in a formal manner;
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meaning of a term may often be “clear,” or uncontroversial in its application to some core set of
circumstances.242 Some have argued that invoking a word’s plain meaning in these cases is
tautological, equivalent to saying that “[w]ords should be read as saying what they say.”243
Moreover, at the margins, when a court is no longer considering a prototypical example of the
disputed statutory term, the judge is called upon to explain how the statute applies to the facts
before the court.244 Therefore, in some cases, merely adverting to the ordinary meaning tool may
not help illuminate a statutory term.245
There are also a number of theoretical criticisms of the “ordinary meaning” standard. Some have
argued that judges might invoke “ordinary meaning” merely to mask their own policy
preferences.246 Judge Easterbrook claimed that frequently, “[t]he invocation of ‘plain meaning’
just sweeps under the rug the process by which meaning is divined.”247 Because “ordinary
meaning” invites judges to refer to their own experiences as English speakers, it is arguably
susceptible to the importation of personal policy preferences.248 Dictionaries or corpus linguistics
may supply a more objective source of evidence of meaning than the judge’s intuitions can, but
those sources may not be focused on a term’s usage in a particular statutory context.249

it also does not find meaning to be ‘plain’ in the sense of being immediately obvious. The inquiry demands argument,
and meaning requires construction.”).
242 Cf. LAWRENCE M. SOLAN, THE LANGUAGE OF JUDGES 98 (1993) (“When we speak of clarity in construing the
concepts expressed by statutes, we are not really making statements about the clarity of the concepts themselves.
Rather, we are expressing judgments about the goodness of fit between the statutory concept and the thing or event in
the world that is the subject of dispute. . . . [For example,] we mean that a truck is such a typical token of the category
vehicle that there should be no controversy about the applicability of the statute to the situation at hand.”).
243 Chapman v. Higbee Co., 319 F.3d 825, 835 (6th Cir. 2003) (Suhrheinrich, J., dissenting) (quoting Reed Dickerson,
THE INTERPRETATION AND APPLICATION OF STATUTES 229 (1975)) (internal quotation marks omitted).
244 Cf. SOLAN, supra note 242, at 13, 26 (arguing most plain meaning is determined by “what linguists call a generative
grammar, the set of internalized rules and principles that permit us, unselfconsciously, to speak and understand
language with ease and with great rapidity,” and claiming that in determining whether a statute is ambiguous, “the
question is whether the meaning of the disputed language is determined fully by our generative grammars, or whether
disputed aspects of the meaning are left open as part of the residue of meaning that our internal grammars do not fully
determine”).
245 Compare, e.g., United States v. Marshall, 908 F.2d 1312, 1317 (7th Cir. 1990) (“LSD is applied to paper in a
solvent; after the solvent evaporates, a tiny quantity of LSD remains. Because the fibers absorb the alcohol, the LSD
solidifies inside the paper rather than on it. You cannot pick a grain of LSD off the surface of the paper. Ordinary
parlance calls the paper containing tiny crystals of LSD a mixture.”); with id. at 1332 (Posner, J., dissenting)
(“[A]pparently some gelatin is part of a ‘mixture or substance’ and some is not. . . . Would the gelatin be a part of the
mixture or substance in an LSD case if a defendant sprayed an LSD-alcohol solution into a capsule, but not if a grain of
LSD were placed into the capsule with a tweezers? It is not enough to say that ‘ordinary usage’ precludes including the
weight of a heavy glass bottle . . . . The words ‘mixture or substance’ are ambiguous . . . .”).
246 See Frederick Schauer, The Practice and Problems of Plain Meaning: A Response to Aleinikoff and Shaw, 45 VAND.
L. REV. 715, 738 (1992) (“It is true that judges have historically tended to mask contested social and political choices of
interpretation of indeterminate texts in the language of linguistic inexorability.”); SOLAN, supra note 242, at 27 (“[T]he
appeal of neutral linguistic principles as justification for a decision will loom especially large when the judge’s ‘real
reasons’ for the decision are not ones that are properly articulated in a judicial opinion.”); Patricia M. Wald, The
Sizzling Sleeper: The Use of Legislative History in Construing Statutes in the 1988–89 Term of the United States
Supreme Court
, 39 AM. U. L. REV. 277, 304 (1990) (“The second alternative source of meaning is for the courts to
supply their own suppositions and assumptions regarding the will of Congress . . . .”).
247 Frank H. Easterbrook, Statutes’ Domains, 50 U. CHI. L. REV. 533, 536 (1983).
248 See Ward Farnsworth et al., Ambiguity about Ambiguity: An Empirical Inquiry into Legal Interpretation, 2 J. OF
LEGAL ANALYSIS 257, 259 (2010); Solan, supra note 170, at 2048 (“[C]ourts find ordinary meaning anywhere they
look and judges are not restrained in deciding where they are willing to look.”).
249 See, e.g., Wright v. Spaulding, 939 F.3d 695, 700 n.1 (6th Cir. 2019) (saying that in the case before the court,
“corpus linguistics turned out not to be the most helpful tool in the toolkit”); see also, e.g., Lawrence M. Solan &
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Statutory Context
Often, a statutory dispute will turn on the meaning of only a few words.250 Courts will interpret
those words, though, in light of the full statutory context.251 To gather evidence of statutory
meaning, a judge may turn to the rest of the provision,252 to the act as a whole,253 or to similar
provisions elsewhere in the law.254 As the Supreme Court said in one opinion, “Statutory
construction . . . is a holistic endeavor. A provision that may seem ambiguous in isolation is often
clarified by the remainder of the statutory scheme. . . .”255
For instance, a court might look to see whether the disputed language is used in another statutory
provision.256 Courts will generally try to give identical terms the same meaning throughout a
statute,257 and another provision may offer context that illuminates the meaning of the relevant
term.258 However, this rule calling for words to be defined consistently is defeasible, again
depending on the context: “A given term in the same statute may take on distinct characters from
association with distinct statutory objects calling for different implementation strategies.”259 For
example, in Azar v. Allina Health Services, the Court concluded that a statutory phrase should be
interpreted consistently throughout the Medicare Act but held that the Medicare Act did not need
to be interpreted consistently with the Administrative Procedure Act.260 The Court’s view was
based on the specific language, context, and functioning of both statutory schemes.261 At least one
scholar has argued that when seeking to compare terms used in different statutes, courts might
reasonably look to whether the statutes deal with similar subjects or were enacted

Tammy Gales, Corpus Linguistics as a Tool in Legal Interpretation, 2018 B.Y.U. L. REV. 1311, 1315 (2017) (noting
limitations inherent in certain databases, including, for example, geographic bias).
250 See, e.g., Yates v. United States, 574 U.S. 528, 536 (2015) (plurality opinion) (considering whether a fish is a
“tangible object” within the meaning of 18 U.S.C. § 1519).
251 See, e.g., id. at 532 (“A fish is no doubt an object that is tangible . . . . But it would cut [18 U.S.C.] § 1519 loose
from its financial-fraud mooring to hold that it encompasses any and all objects . . . .”).
252 E.g., NLRB v. SW Gen., Inc., 137 S. Ct. 929, 938–39 (2017) (considering disputed terms from statutory subsection
individually and then considering them as a whole).
253 E.g., FCC v. AT&T Inc., 562 U.S. 397, 407–08 (2011) (considering meaning of “personal privacy” in light of its use
in a distinct but similar exemption within the same statute); Holder v. Hall, 512 U.S. 874, 883 (1994) (comparing the
functioning of two sections within the Voting Rights Act of 1965 that “differ in structure, purpose, and application”).
254 E.g., Unicolors, Inc. v. H&M Hennes & Mauritz, L.P., 142 S. Ct. 941, 947 (2022) (looking to how “nearby statutory
provisions” use a specific word); Peter v. NantKwest, Inc., 140 S. Ct. 365, 373 (2019) (looking to how two statutory
phrases were used “across various statutes” dealing with similar subjects). In their book cataloguing the canons of
construction, Justice Scalia and Bryan Garner describe this concept as part of the “whole text canon.” SCALIA &
GARNER, supra note 24, at 167; cf. Anita S. Krishnakumar, Cracking the Whole Code Rule, 96 N.Y.U.L. REV. 76
(2021) (reviewing the practice and identifying five types of whole code comparisons: (1) modeled, borrowed, and
incorporated statutes; (2) consistent usage; (3) meaningful variation; (4) superfluity; and (5) harmonization).
255 United Sav. Ass’n of Tex. v. Timbers of Inwood Forest Assocs., Ltd., 484 U.S. 365, 371 (1988).
256 See United Sav. Ass’n of Tex., 484 U.S. at 371. See also, e.g., Brown v. Gardner, 513 U.S. 115, 118 (1994) (looking
to how a term is used in “analogous statutes”).
257 E.g., Cochise Consultancy, Inc. v. United States ex rel. Hunt, 139 S. Ct. 1507, 1512 (2019).
258 E.g., Smith v. United States, 508 U.S. 223, 234 (1993).
259 Envtl. Def. v. Duke Energy Corp., 549 U.S. 561, 574 (2007).
260 Azar v. Allina Health Servs., 139 S. Ct. 1804, 1811–13 (2019) (interpreting a Medicare Act provision that required
notice and comment procedures for rules or other policy statements that established a “substantive legal standard”).
261 See id.
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contemporaneously.262 The scholar further found, however, that only the second factor was
considered consistently by the Supreme Court.263
A judge might also look to the rest of the statute to find whether Congress used different language
in other provisions. If Congress elsewhere used language that more clearly captured an
interpretation urged by one of the parties, it might suggest that the disputed term should not be
given that construction.264 Courts will generally read as meaningful “the exclusion of language
from one statutory provision that is included in other provisions of the same statute.”265 Some
have questioned, however, whether this “meaningful variation form of cross-statute comparison”
is consistent with congressional practice.266
Thus, statutory context can supply evidence of semantic, or text-focused, context. In Smith v.
United States
, for example, a defendant challenged his sentence following conviction for a drug
trafficking offense during which he offered to trade a gun for cocaine.267 The Supreme Court had
to decide whether the defendant should be subject to a sentence enhancement that applied to any
“‘use’ of a firearm ‘during and in relation to . . . [a] drug trafficking crime.’”268 The defendant
argued that this enhancement should apply only when a firearm was “used as a weapon,” not
when it was used to barter for drugs.269 The Supreme Court disagreed.270
During the course of its analysis, the Court investigated how Congress had employed the term
“use” in other provisions of the statute.271 The Court found it compelling that a different
subsection of the statute called for forfeiture of a firearm that was “used” in an interstate transfer
of a firearm or in a federal offense involving the exportation of a firearm.272 In the eyes of the
Court, this other provision clearly contemplated that firearms could be “used” “as items of
commerce rather than as weapons,”273 suggesting the same interpretation of “used” should apply
to the disputed sentence enhancement.274 The Court also explained that Congress had used the
phrase “involved in” instead of the word “use” elsewhere in the statute.275 Specifically, a different
provision allowed the seizure of a firearm that was “‘involved in’ . . . the making of a false
statement material to the lawfulness of a gun’s transfer.”276 The Court reasoned that this

262 See Krishnakumar, Cracking the Whole Code Rule, supra note 254, at 103.
263 Id. at 104, 108 (reviewing “data from the Roberts Court’s first twelve-and-a-half Terms”).
264 E.g. City of Chicago v. Envtl. Def. Fund, 511 U.S. 328, 337–38 (1994) (“Our interpretation is confirmed by
comparing [the disputed statute] with another statutory exemption in [the same act]. . . . [T]his [other] provision shows
that Congress knew how to draft a waste stream exemption . . . when it wanted to.” (internal quotation marks omitted)).
265 Hamdan v. Runsfeld, 548 U.S. 557, 578 (2006).
266 Krishnakumar, Cracking the Whole Code Rule, supra note 254, at 150–51. See also, e.g., Caraco Pharm. Labs., Ltd.
v. Novo Nordisk A/S, 566 U.S. 399, 416 (2012) (“[T]he mere possibility of clearer phrasing cannot defeat the most
natural reading of a statute; if it could (with all due respect to Congress), we would interpret a great many statutes
differently than we do.”).
267 Smith v. United States, 508 U.S. 223, 226–27 (1993).
268 Id. at 225 (alteration in original) (quoting 18 U.S.C. § 924(c)(1)).
269 Id. at 227.
270 Id. at 225.
271 Id. at 233.
272 Id. at 234.
273 Id. at 235.
274 Id. at 235–36.
275 Id. at 235.
276 Id. (quoting 18 U.S.C. § 924(d)(1)).
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distinction demonstrated that Congress found it was necessary in the other provision to use more
expansive language because “making a material misstatement in order to acquire or sell a gun is
not ‘use’ of the gun.”277 By contrast, Congress “did not so expand the language for offenses in
which firearms were ‘intended to be used,’ even though the firearms in many of those offenses
function as items of commerce rather than as weapons.”278 Therefore, according to the majority
opinion, “Congress apparently was of the view that one could use a gun by trading it.”279
Statutory context can also help a court determine how the disputed terms fit into the rest of the
law, illuminating the purpose of a provision.280 Courts may consider statutory declarations of
purpose as well as the broad functioning of the statutory scheme.281 Judges sometimes weigh the
practical consequences of the various proposed interpretations, as discussed in more detail in a
later section.282 It could be that “only one of the permissible meanings produces a substantive
effect that is compatible with the rest of the law.”283 This use of statutory context often implicates
the broader debate between purposivism and textualism,284 as well as arguments over when
judges should use practical consequences to determine statutory meaning.285
Canons of Construction
Over time, courts have created the “canons of construction” to serve as guiding principles for
interpreting statutes.286 The canons supply default assumptions about the way Congress generally
expresses meaning,287 but are not “rules” in the sense that they must invariably be applied.288 A
judge may decline to interpret a statute in accordance with any given canon if the canon’s
application is not justified in that case.289 In some cases, two canons may appear to apply but

277 Id.
278 Id. (quoting 18 U.S.C. § 924(d)(3)) (emphasis added).
279 Id. See also, e.g., Babcock v. Kijakazi, 142 S. Ct. 641, 645–46 (2022) (concluding statutory context confirmed
statute’s plain meaning treating military technicians as civilians, because other statutory provisions “consistently
distinguished technician employment from National Guard service”).
280 E.g., Freeman v. Quicken Loans, Inc., 566 U.S. 624, 632 (2012) (rejecting an interpretation that would undermine
the purpose of a statute by imposing liability on “the very class for whose benefit [the statute] was enacted”).
281 E.g. United States v. Turkette, 452 U.S. 576, 589 (1981) (considering statutory declaration of purpose and
evaluating “various Titles of the Act” as “the tools through which this goal is to be accomplished”).
282 E.g., Krishnakumar, Reconsidering Substantive Canons, supra note 199, at 887 (noting empirical evidence that the
Supreme Court frequently uses practical consequences to interpret statutes). See, e.g., King v. Burwell, 576 U.S. 473,
490–91 (2015) (considering meaning of statutory phrase in light of the functioning of the entire Patient Protection and
Affordable Care Act); id. at 2494 (“It is implausible that Congress meant the Act to operate in this manner.”). For more
information on statutory operation as a distinct tool, see infra “Practical Consequences.”
283 United Sav. Ass’n of Tex. v. Timbers of Inwood Forest Assocs., Ltd., 484 U.S. 365, 371 (1988).
284 Compare, e.g., Freeman, 566 U.S. at 637 (“Vague notions of statutory purpose provide no warrant for expanding [a
statute’s] prohibition beyond the field to which it is unambiguously limited . . . .”), with King, 576 U.S. at 497 (“In this
instance, the context and structure of the Act compel us to depart from what would otherwise be the most natural
reading of the pertinent statutory phrase.”).
285 See infra “Practical Consequences.”
286 E.g. MIKVA & LANE, supra note 9, at 114 (“Canons of construction are judicially crafted maxims or aphorisms for
determining the meaning of statutes. Canons are expressly intended to limit judicial discretion by rooting interpretive
decisions in a system of aged and shared principles . . . .”).
287 See, e.g., Nelson, supra note 101, at 383.
288 HART & SACKS, supra note 17, at 1191; SCALIA & GARNER, supra note 24, at 51.
289 See, e.g., Michael Sinclair, “Only a Sith Thinks Like That”: Llewellyn’s “Dueling Canons,” One to Seven, 50
N.Y.L. SCH. L. REV. 919, 923 (2005) (“The application of a canon depends on its justification. When the conditions
presupposed by a canon do not obtain, then it should not be used. . . . A canon . . . looks more like a formulaic summary
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support different interpretations.290 Some judges, especially purposivists and some pragmatists,
may even doubt the general validity of the canons as interpretive rules.291 Nonetheless, the canons
are widely used and defended, as discussed in more detail below.292
Judges may also disagree on what qualifies as a valid canon, either as a matter of theory or
historical fact.293 These disagreements will sometimes stem from a judge’s individual theory of
statutory interpretation and their justifications for using the canons more generally.294 This
report’s Appendix combines two preeminent anthologies of the canons of construction, providing
a list of widely accepted canons of construction.295 However, even the authors of these prominent
lists disagree about whether certain canons are valid.296 This report does not attempt to resolve
those disputes and set out a definitive compilation of the canons of construction, but merely
describes the canons generally, giving examples where appropriate. Furthermore, new canons
may emerge over time. For example, this report does not discuss the “major questions
doctrine,”297 a relatively new interpretive rule—still with an uncertain scope—that requires
Congress to speak clearly if it gives an agency authority over an issue of “vast ‘economic and
political significance.’”298
Generally, legal scholars and judges divide the canons into two groups: semantic and substantive
canons.299

of the end result of a process of reasoning, but a process sufficiently commonplace to justify a canonical formula.”).
290 See, e.g., Lockhart v. United States, 577 U.S. 347 (2016). Lockhart is discussed infra “Semantic Canons.”
291 See, e.g., Breyer, supra note 32, at 869–71; Posner, Statutory Interpretation—in the Classroom and in the
Courtroom
, supra note 125, at 806–07.
292 Infra “Justifications: Disrepute, Rehabilitation, and Empirical Studies.See also, e.g., Mendelson, supra note 199, at
75.
293 See, e.g., Nelson, supra note 101, at 386 (asking “What Makes Canons Canonical?”).
294 See, e.g., Manning, Legal Realism & the Canons’ Revival, supra note 176, at 288 (describing why some theorists
disfavor the canons).
295 SCALIA & GARNER, supra note 24; WILLIAM N. ESKRIDGE, JR., PHILLIP P. FRICKEY, ELIZABETH GARRETT, & JAMES J.
BRUDNEY, CASES AND MATERIALS ON LEGISLATION AND REGULATION: STATUTES AND THE CREATION OF PUBLIC POLICY
(5th ed. 2014). The list in the latter casebook builds upon the list given in William N. Eskridge, Jr. & Philip P. Frickey,
Foreword: Law As Equilibrium, 108 HARV. L. REV. 26, 97–108 (1994).
296 Compare, e.g., SCALIA & GARNER, supra note 24, at 359 (describing as a “false notion” the idea that statutory
exemptions should be strictly construed), with Eskridge & Frickey, Law As Equilibrium, supra note 295, at 105
(describing the “narrow interpretation of statutory exemptions” as a canon). See generally, e.g., Evan C. Zoldan, Canon
Spotting
, 59 HOUS. L. REV. 621, 629 (2022) (suggesting three criteria for identifying a canon: “it reflects use by legal
interpreters; it affects an interpretive outcome when applied; and it is supported by a claim of theoretical justification”).
297 For more discussion of this issue, see CRS In Focus IF12077, The Major Questions Doctrine, by Kate R. Bowers.
Compare West Virginia v. EPA, 142 S. Ct. 2587, 2609 (2022) (saying the Court’s cases applying the major questions
doctrine have used an approach “distinct” from “routine statutory interpretation”), with Gundy v. United States, 139 S.
Ct. 2116, 2142 (2019) (Gorsuch, J., dissenting) (describing the “major questions doctrine” as “nominally a canon of
statutory construction”).
298 Util. Air Regul. Grp. v. EPA, 573 U.S. 302, 324 (2014) (quoting FDA v. Brown & Williamson Tobacco Corp., 529
U.S. 120, 160 (2000)). The major questions doctrine is related to the “elephants in mouseholes” principle, which is
mentioned elsewhere in the report. Infra note 484; notes 598 to 599 and accompanying text. See also, e.g., Nathan
Richardson, Keeping Big Cases from Making Bad Law: The Resurgent “Major Questions” Doctrine, 49 CONN. L. REV.
355, 373 (2016) (arguing this principle has “its roots in the major questions doctrine”).
299 E.g., JOHN F. MANNING & MATTHEW C. STEPHENSON, LEGISLATION AND REGULATION: CASES AND MATERIALS 202
(2d ed. 2013).
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Semantic Canons
The semantic, or textual, canons represent “rules of thumb for decoding legal language.”300
Because these canons focus on statutory text, they are often favored by textualists.301 The
semantic canons frequently reflect the rules of grammar that govern ordinary language usage.302
Consequently, these rules may overlap with indicators of a provision’s ordinary meaning303—and
indeed, some authors label the principle that words should be given their ordinary meaning as a
semantic canon.304 But there are a greater number of semantic canons beyond the ordinary
meaning rule, several of which are discussed below.
For example, the “grammatical ‘rule of the last antecedent’” states that “a limiting clause or
phrase . . . should ordinarily be read as modifying only the noun or phrase that it immediately
follows.”305 In Barnhart v. Thomas, the Supreme Court illustrated this canon with the following
hypothetical:
Consider, for example, the case of parents who, before leaving their teenage son alone in
the house for the weekend, warn him, “You will be punished if you throw a party or engage
in any other activity that damages the house.” If the son nevertheless throws a party and is
caught, he should hardly be able to avoid punishment by arguing that the house was not
damaged. The parents proscribed (1) a party, and (2) any other activity that damages the
house.306
The last-antecedent canon tells the reader of the parents’ edict that the descriptive clause “that
damages the house” refers to the “nearest reasonable antecedent”: here, “any other activity.”307

300 Id. at 204.
301 Manning, Legal Realism & the Canons’ Revival, supra note 176, at 290 (“Because textualists believe in a strong
version of legislative supremacy, their skepticism about actual [legislative] intent or purpose has . . . inspired renewed
emphasis on the canons of interpretation, particularly the linguistic or syntactic canons of interpretation.”); id. at 292
(“[T]extualists deem it essential to foster clear and predictable linguistic and syntactic rules to permit legislators and
interpreters to decode enacted texts.”).
302 E.g., Kavanaugh, supra note 131, at 2159–60. But see Adam Schlusselberg & Michael Sinclair, ‘Only a Sith Thinks
Like That’: Llewellyn’s ‘Dueling Canons’, Twenty-Five to Twenty-Eight
36 (Sept. 24, 2010) (N.Y. Law Sch. Research
Paper Series 10/11 #3), https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1682164 (questioning whether it is
“productive to call the rules of grammar ‘canons of construction’”).
303 E.g., MANNING & STEPHENSON, supra note 299, at 204–05.
304 E.g., SCALIA & GARNER, supra note 24, at 69. Cf. MIKVA & LANE, supra note 9, at 114 (“The authors do not, as
some do, define the plain meaning rule as a canon of construction. This is based on our view that the plain meaning rule
is the constitutionally compelled starting place for any statutory construction and that tools of interpretation are only
applicable when, for whatever reason, the plain meaning rule fails to provide the answer.”). Judges also disagree about
whether the plain meaning rule is a special and superior canon. Compare, e.g., State v. Peters, 665 N.W.2d 171, 177–78
(Wis. 2003) (Abrahamson, C.J., concurring) (arguing plain meaning rule, as well as rules saying courts may use
dictionaries and that statutory definitions must control, are all canons, and arguing that all canons representing
“‘[i]ntrinsic aids’ to construction . . . are essential to any application of the plain meaning rule”), with Metro One
Telecomms., Inc. v. Comm’r, 704 F.3d 1057, 1063 (9th Cir. 2012) (“[W]here the plain meaning rule has provided a
clear answer, we do not need to look to other canons of statutory construction.”).
305 Barnhart v. Thomas, 540 U.S. 20, 26 (2003). See also Lockhart v. United States, 577 U.S. 347, 351 (2016) (“The
rule reflects the basic intuition that when a modifier appears at the end of a list, it is easier to apply that modifier only to
the item directly before it. That is particularly true where it takes more than a little mental energy to process the
individual entries in the list, making it a heavy lift to carry the modifier across them all.”).
306 Barnhart, 540 U.S. at 27.
307 See SCALIA & GARNER, supra note 24, at 144–45 (discussing Barnhart and the Court’s hypothetical).
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Accordingly, that clause modifies only the phrase “any other activity,” and not “party,” a more
remote antecedent.308
In Lockhart v. United States, the Supreme Court applied the last-antecedent canon to interpret a
federal criminal statute that imposed a 10-year mandatory minimum sentence on any person
possessing child pornography309 if that person had “a prior conviction . . . under the laws of any
State relating to aggravated sexual abuse, sexual abuse, or abusive sexual conduct involving a
minor or ward.”310 The question before the Court was “whether the limiting phrase that appears at
the end of that list—‘involving a minor or ward’—applies to all three predicate crimes preceding
it in the list or only the final predicate crime.”311 Invoking the rule of the last antecedent, the
Court concluded that the limiting phrase “modifies only the phrase that it immediately follows:
‘abusive sexual conduct.’”312
The dissenting opinion in Lockhart argued that a different semantic canon, the “series-qualifier
canon,” applied instead of the last-antecedent canon.313 The “series-qualifier” canon provides that
under certain circumstances, a modifier should be applied to all terms in a list.314 Because the
modifying clause “involving a minor or ward” followed “a list of multiple, parallel terms,” the
dissent claimed that it should apply to the entire series.315 In the dissenters’ view, “the reference to
a minor or ward applies as well to sexual abuse and aggravated sexual abuse as to abusive sexual
conduct.”316 By contrast, the majority of the Court believed the series-qualifier canon was
inapplicable, concluding that the disputed provision “does not contain items that readers are used
to seeing listed together or a concluding modifier that readers are accustomed to applying to each
of them.”317 Further, the majority argued, “the varied syntax of each item in the list makes it hard
for the reader to carry the final modifying clause across all three.”318 Lockhart therefore
demonstrates the complexities of applying the canons of construction, particularly when different
canons suggest different interpretations.
Another semantic canon, the rule against surplusage, relies less on the niceties of grammar and
more on the general principles underlying how courts assume Congress conveys meaning.319 The
surplusage canon requires courts to give each word and clause of a statute operative effect, if

308 See id. at 145.
309 18 U.S.C. § 2252(a)(4).
310 Lockhart, 577 U.S. at 349 (quoting 18 U.S.C. § 2252(b)(2)).
311 Id. (quoting 18 U.S.C. § 2252(b)(2)).
312 Id. at 352 (quoting 18 U.S.C. § 2252(b)(2)).
313 Id. at 364 (Kagan, J., dissenting) (quoting BLACK’S LAW DICTIONARY 1574 (10th ed. 2014)) (internal quotation
marks omitted).
314 Id. (citing SCALIA & GARNER, supra note 24, at 147).
315 Id. at 363–64. Cf. id. at 364–65 (“When the nouns in a list are so disparate that the modifying clause does not make
sense when applied to them all, then the last-antecedent rule takes over. Suppose your friend told you not that she wants
to meet ‘an actor, director, or producer involved with Star Wars,’ [in which case the modifier would apply to the entire
list] but instead that she hopes someday to meet ‘a President, Supreme Court Justice, or actor involved with Star Wars.’
Presumably, you would know that she wants to meet a President or Justice even if that person has no connection to the
famed film franchise.”).
316 Id. at 366.
317 Id. at 352 (majority opinion).
318 Id.
319 See SCALIA & GARNER, supra note 24, at 174. This canon is also sometimes referred to as the “canon against
superfluity.” See, e.g., Microsoft Corp. v. i4i Ltd. P’ship, 564 U.S. 91, 106 (2011).
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possible.320 Stated another way, courts should not interpret any statutory provision in a way that
would render it or another part of the statute inoperative or redundant.321 Accordingly, for
example, when a court is faced with a statutory list of terms, it generally will read each term to
convey some distinct meaning.322 In Bailey v. United States, the Supreme Court considered a
statute that imposed a five-year mandatory minimum sentence on a person who “uses or carries a
firearm” during a crime of violence or drug trafficking crime.323 The Court refused to give the
term “use” such a broad reading that “no role remains for ‘carry.’”324 Instead, the Court assumed
“that Congress used two terms because it intended each term to have a particular, nonsuperfluous
meaning,” and gave “use” a more limited connotation that “preserve[d] a meaningful role for
‘carries’ as an alternative basis for a charge.”325
Elsewhere, however, judges have questioned whether the assumption underlying the surplusage
canon is true or whether instead it is more likely that Congress sometimes does use redundant
language.326 In one case, the Supreme Court noted that “redundancies are common in statutory
drafting—sometimes in a congressional effort to be doubly sure, sometimes because of
congressional inadvertence or lack of foresight, or sometimes simply because of the shortcomings
of human communication.”327 This discussion demonstrates the idea that the canons are
presumptions, rather than rules, and cannot replace a broader contextual inquiry.328
Substantive Canons
In contrast to the semantic canons, the substantive canons express “judicial presumption[s] . . . in
favor of or against a particular substantive outcome.”329 Some of these canons, particularly those
that protect constitutional values, are described as “clear statement rules” because courts will
favor certain outcomes unless the statute makes a “clear statement” that unambiguously dislodges
the presumption.330 The substantive canons “look to the legal consequences of interpretation

320 See Duncan v. Walker, 533 U.S. 167, 174 (2001).
321 See, e.g., Fourth Estate Pub. Ben. Corp. v. Wall-Street.com, LLC, 139 S. Ct. 881, 889 (2019); Colautti v. Franklin,
439 U.S. 379, 392 (1979). But see, e.g., Rimini St., Inc. v. Oracle USA, Inc., 139 S. Ct. 873, 881 (2019) (stating that
this rule “is not a silver bullet” and acknowledging that “[s]ometimes the better overall reading of the statute contains
some redundancy”).
322 See, e.g., McDonnell v. United States, 579 U.S. 550, 569 (2016).
323 Bailey v. United States, 516 U.S. 137, 138–39 (1995) (quoting 18 U.S.C. § 924(c)(1)) (internal quotation mark
omitted).
324 Id. at 145.
325 Id. at 146.
326 See, e.g., Microsoft Corp. v. i4i Ltd. P’ship, 564 U.S. 91, 106 (2011) (noting that “no interpretation” of the relevant
statute “avoids excess language”); id. at 107 (“‘There are times when Congress enacts provisions that are superfluous,’
and the kind of excess language [at issue] . . . is hardly unusual in comparison to other [similar] statutes . . . .” (quoting
Corley v. United States, 556 U.S. 303, 325 (2009) (Alito, J., dissenting))); Hively v. Ivy Tech Cmty. Coll. of Ind., 853
F.3d 339, 344 (7th Cir. 2017) (“Congress may certainly choose to use both a belt and suspenders to achieve its
objectives . . . .”).
327 Barton v. Barr, 140 S. Ct. 1442, 1453 (2020).
328 See also infra “Justifications: Disrepute, Rehabilitation, and Empirical Studies.”
329 MANNING & STEPHENSON, supra note 299, at 202.
330 See, e.g., HART & SACKS, supra note 17, at 1376; Manning, Textualism and the Equity of the Statute, supra note 32,
at 121–22.
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rather than to linguistic issues alone.”331 If a statute is susceptible to more than one meaning, they
may tip the scale toward a particular result.332
Accordingly, invocation of the substantive canons frequently invites judicial disagreement.333 The
canon of constitutional avoidance provides a good example of how even a well-established334
substantive canon can provoke debate.335 The canon of constitutional avoidance provides that if
one plausible reading of a statute would raise “serious doubt” about the statute’s constitutionality,
a court should look for another, “fairly possible” reading that would avoid the constitutional
issue.336 Thus, for instance, the constitutional-avoidance canon might lead a court to adopt a
limiting construction of a statutory provision, if a broader interpretation would allow the
government to exercise a constitutionally problematic amount of power.337
The constitutional-avoidance canon may allow a court to adopt a “reasonable alternative
interpretation”338 even if it is not otherwise “the most natural interpretation” of the disputed
statute.339 For example, in Bond v. United States, the Supreme Court interpreted a statute making
it a crime for a person to use “any chemical weapon.”340 The Court noted that the “expansive
language” of the statute could be read to encompass the conduct of the defendant, who had placed
toxic chemicals on the car door, mailbox, and door knob of a friend after discovering that the
friend had become pregnant by the defendant’s husband.341 However, the Court decided that it
would not interpret the statute “to reach purely local crimes”342 because such an interpretation
would intrude on powers traditionally reserved for the states, implicating constitutional concerns
about the balance of power between the federal government and the states.343 Instead, the Court
read the statute more narrowly, to exclude the defendant’s conduct.344

331 SOLAN, supra note 242, at 65.
332 See id. (stating substantive canons “stack the deck in favor of one party and against another”); Scalia, supra note 84,
at 27 (referring to “rules of construction that load the dice for or against a particular result”).
333 See, e.g., ESKRIDGE ET AL., supra note 40, at 342.
334 See Edward J. DeBartolo Corp. v. Fla. Gulf Coast Bldg. & Constr. Trades Council, 485 U.S. 568, 575 (1988)
(saying the canon “has for so long been applied by this Court that it is beyond debate”).
335 See, e.g., ESKRIDGE ET AL., supra note 40, at 362–67 (discussing arguments for and against using the canon).
336 Crowell v. Benson, 285 U.S. 22, 62 (1932). This canon is distinct from other variations on the principle of
constitutional avoidance, including the “rule of judicial procedure” stating that “‘if a case can be decided on either of
two grounds, one involving a constitutional question, the other a question of statutory construction . . . , the Court will
decide only the latter.’” See SCALIA & GARNER, supra note 24, at 251 (quoting Ashwander v. Tenn. Valley Auth., 297
U.S. 288, 347 (1936) (Brandeis, J., concurring)). The procedural rule tells a court when to decide a statutory question
(i.e., before the constitutional question); the canon tells a judge how to interpret the statute. MANNING & STEPHENSON,
supra note 299, at 250. This report uses the term to refer to the canon, although there is room for disagreement
regarding how to classify various aspects of the constitutional avoidance doctrine. For more information on the
doctrine, see CRS Report R43706, The Doctrine of Constitutional Avoidance: A Legal Overview, by Andrew Nolan.
337 See, e.g., Gomez v. United States, 490 U.S. 858, 863–64 (1989) (noting that “read literally,” disputed statute would
allow federal magistrate to take on “any assignment that is not explicitly prohibited,” and instead adopting an
alternative interpretation—that the additional duties must be related to statutorily specified duties of the office).
338 Id. at 864.
339 Nat’l Fed’n of Indep. Bus. v. Sebelius, 567 U.S. 519, 563 (2012).
340 572 U.S. 844, 851 (2014) (quoting 18 U.S.C. 229(a)(1) (quotation mark omitted)).
341 Id. at 860–61.
342 Id. at 860.
343 Id. at 862–63.
344 Id. at 866.
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Of course, judges may disagree on whether an alternative reading that avoids a constitutional
problem is “fairly possible.”345 As the Supreme Court emphasized in one case, the constitutional-
avoidance canon “does not give a court the authority to rewrite a statute as it pleases.”346
Accordingly, the Court has rejected application of the canon if the text “unambiguously
forecloses” the proferred construction.347
Many of the substantive canons entail difficult judgments in determining whether triggering
threshold conditions have been met.348 In the case of the canon of constitutional avoidance, a
court need not conclude that a suggested reading of the statute in fact would render the statute
unconstitutional; the canon requires only that there is a “serious doubt” about the constitutionality
of the proffered interpretation.349 Judges disagree, however, on how much constitutional “doubt”
must be present before a court may use the constitutional-avoidance canon to support a certain
interpretation of a statute.350 As one treatise puts it: “How doubtful is doubtful?”351 Some judges
have argued that the constitutional-avoidance canon should be used sparingly, if at all.352
At a more general level, judges frequently disagree about whether substantive canons are
appropriately used to interpret statutes, both in theory and in practical application.353 This
disagreement sometimes stems from different beliefs about the general justifications for using the
canons.354 To the extent that the substantive canons suggest that a judge should read a statute in a
way that is not immediately evident from the statute’s text or purpose, both textualists and
purposivists may be wary of employing these canons.355 Consequently, most courts will not apply

345 Crowell v. Benson, 285 U.S. 22, 62 (1932). See also Eric S. Fish, Constitutional Avoidance as Interpretation and as
Remedy
, 114 MICH. L. REV. 1275, 1285 (2016) (distinguishing “tiebreaking avoidance,” in which the canon may be
used to choose one of two similarly plausible interpretations, from “rewriting avoidance,” in which the canon may be
used “to select a less-accurate interpretation”).
346 Jennings v. Rodriguez, 138 S. Ct. 830, 843 (2018).
347 United States v. Palomar-Santiago, 141 S. Ct. 1615, 1622 (2021). See also, e.g., Holder v. Humanitarian Law
Project, 561 U.S. 1, 17 (2010) (rejecting invocation of canon where construction would “revise” the law rather than
interpret it, and “pervert[] the purpose of” the disputed law).
348 Compare, e.g., Muscarello v. United States, 524 U.S. 125, 138–39 (1998) (concluding statute is not sufficiently
ambiguous to make the rule of lenity applicable), with id. at 148–49 (Ginsburg, J., dissenting) (arguing rule of lenity
should apply to resolve statutory ambiguity).
349 Crowell, 285 U.S. at 62. Cf. Brown v. Plata, 563 U.S. 493, 526 (2011) (concluding reading is “permissible” because
the alternative interpretation “would raise serious constitutional concerns”); Legal Servs. Corp. v. Velazquez, 531 U.S.
533, 545 (2001) (“It is well understood that when there are two reasonable constructions for a statute, yet one raises a
constitutional question, the Court should prefer the interpretation which avoids the constitutional issue.”).
350 Anthony Vitarelli, Comment, Constitutional Avoidance Step Zero, 119 YALE L.J. 837, 841–42 (2010).
351 SCALIA & GARNER, supra note 24, at 250. Compare, e.g., United States v. X-Citement Video, Inc., 513 U.S. 64, 78
(1994) (determining constitutional-avoidance canon supports reading mens rea requirement into statute because statute
would otherwise “raise serious constitutional doubts”), with id. at 83 (Scalia, J., dissenting) (arguing statute does not
raise serious constitutional doubts).
352 See, e.g., United States v. Marshall, 908 F.2d 1312, 1335–36 (7th Cir. 1990) (Posner, J., dissenting) (“Courts often
do interpretive handsprings to avoid having even to decide a constitutional question. In doing so they expand, very
questionably in my view, the effective scope of the Constitution, creating a constitutional penumbra in which statutes
wither, shrink, are deformed. A better case for flexible interpretation is presented when the alternative is to nullify
Congress’s action: when in other words there is not merely a constitutional question about, but a constitutional barrier
to, the statute when interpreted literally.” (citation omitted)).
353 See, e.g., ESKRIDGE ET AL., supra note 40, at 342 (“The substantive canons of interpretation . . . are even more
controversial, because they are rooted in broader policy or value judgments.”).
354 See, e.g., MANNING & STEPHENSON, supra note 299, at 248 (discussing possible justifications for the canons of
construction).
355 See, e.g., Manning, Textualism and the Equity of the Statute, supra note 32, at 125; Nelson, supra note 101, at 393–
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the substantive canons unless they conclude that after consulting other interpretive tools, the
statute remains ambiguous.356 Again, however, such a conclusion often presents a debatable
question about whether a statute is sufficiently ambiguous to call for the application of a
substantive canon.357
Justifications: Disrepute, Rehabilitation, and Empirical Studies
Judges may choose not to apply a canon to resolve a statutory ambiguity if they disagree with the
justifications generally proffered to justify that canon, or if they simply believe that those general
justifications do not warrant its extension to the case before them.358 The canons of construction
were a disfavored tool of statutory interpretation for a significant portion of the 20th century.359
This view was reflected in a frequently cited article written by legal scholar Karl Llewellyn in
1950, in which he argued that the canons were not useful interpretive tools because of their
indeterminacy.360 He compiled a table of “thrusts” and “parries” that purported to demonstrate
that for every canon, there was an opposing canon on the same point.361 For example, one thrust
declares that “[w]ords and phrases which have received judicial construction before enactment
are to be understood according to that construction,” while the parry counters, “[n]ot if the statute
clearly requires them to have a different meaning.”362 Some modern judges have agreed with this
criticism, arguing that judges effectively “need a canon for choosing between competing
canons.”363
Others, however, have challenged Llewellyn’s list, questioning the validity of the rules that he
claimed were canons.364 Scholars and judges have also cast doubt on whether his thrusts and

94.
356 Compare, e.g., Beecham v. United States, 511 U.S. 368, 374 (1994) (“Because the statutory language is
unambiguous, the rule of lenity, which petitioners urge us to employ here, is inapplicable.”), with Liparota v. United
States, 471 U.S. 419, 427–28 (1985) (“Although the rule of lenity is not to be applied where to do so would conflict
with the implied or expressed intent of Congress, it provides a time-honored interpretive guideline when the
congressional purpose is unclear. In the instant case, the rule directly supports petitioner’s contention that the
Government must prove knowledge of illegality to convict him . . . .”). See also, e.g., United States v. Monsanto, 491
U.S. 600, 611 (1989) (noting the canons “are quite often useful in close cases, or when statutory language is
ambiguous,” but declining to use them where “the language is clear and the statute comprehensive”).
357 See supra note 348.
358 E.g., supra notes 289 and 291.
359 E.g. MIKVA & LANE, supra note 9, at 115 (“The use of canons of construction for the interpretation of statutes has
been held in scholarly ill repute for over a century.”). Cf. Posner, Statutory Interpretation—in the Classroom and in the
Courtroom
, supra note 125, at 805 (“[I]t has been many years since any legal scholar had a good word to say about any
but one or two of the canons, but scholarly opinion . . . has had little impact on the writing of judicial opinions, where
the canons seem to be flourishing as vigorously as ever.”).
360 Llewellyn, supra note 72, at 401. Cf. Frankfurter, supra note 8, at 544 (“[C]anons of construction . . . give an air of
abstract intellectual compulsion to what is in fact a delicate judgment . . . .”); id. at 544–45 (arguing canons are valid
only insofar as they are flexible “axioms of experience” that judges may revisit and adapt through application).
361 Llewellyn, supra note 72, at 401. See also SEC v. C. M. Joiner Leasing Corp., 320 U.S. 344, 353 (1943) (“Some
authority is cited and a great array could be assembled to support the general proposition that penal statutes must be
strictly construed. An almost equally impressive collection can be made of decisions holding that remedial statutes
should be liberally construed. What, then, shall we say of the construction of a [statute] like this which may be the basis
of either civil proceedings of a preventive or remedial nature or of punitive proceedings, or perhaps both?”).
362 Llewellyn, supra note 72, at 403.
363 Posner, Statutory Interpretation—in the Classroom and in the Courtroom, supra note 125, at 806.
364 See, e.g., Scalia, supra note 84, at 26–27 (identifying two examples of “faux canons”). Cf. Michael Sinclair, “Only a
Sith Thinks Like That”: Llewellyn’s “Dueling Canons,” Pairs Thirteen to Sixteen
, 53 N.Y.L. SCH. L. REV. 953, 985
(2008/09) (questioning the provenance of Llewellyn’s formulation of the canons).
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parries are truly contradictory, arguing that many of his pairs instead represent two halves of one
rule, the thrust giving the general rule, and the parry, the exception or condition.365 By and large,
the canons of construction have been rehabilitated among jurists and legal scholars, primarily by
textualists, who have argued on a number of bases that the canons represent “sound interpretive
conventions.”366
The foregoing criticisms, however, have forced many judges to more diligently justify their use of
the canons. One scholar has placed the canons into two categories based on the justifications
given for their canonization.367 For that scholar, the first group of canons is descriptive; such
canons “simply reflect broader conventions of language use, common in society at large at the
time the statute was enacted.”368 Judges invoke these canons because, according to this scholar,
they are accurate descriptions of the way that all people use words.369 As a result, courts expect
that these principles will also apply to legislative drafting.370 The scholar describes the second
group of canons as normative.371 These normative canons are “used primarily by lawyers” rather
than society at large and “relate specifically to the interpretation of statutes.”372 Courts may think
that these canons, as well, accurately capture insights about congressional behavior.373 But judges
might also apply these canons as a matter of historical practice,374 or because they believe the

365 See Scalia, supra note 84, at 27; Schlusselberg & Sinclair, supra note 302, at 38. See, e.g., Landgraf v. USI Film
Prods., 511 U.S. 244, 264, 280 (1994) (noting “apparent tension” between two canons and resolving the conflict). Cf.
SOLAN, supra note 242, at 31 (suggesting some canons embody two “types of devices,” reflecting the way English
speakers generally understand language: “[1] interpretive strategies that function to ease the rapid processing of
language as it is heard or read, but which can be overridden if their application leads to nonsensical or ungrammatical
interpretations of sentences, and [2] rules of grammar, which make certain interpretations impossible,” and questioning
whether judges apply the canons consistently with linguistic theory).
366 E.g., SCALIA & GARNER, supra note 24, at xxvii (“Nothing but conventions and contexts cause a symbol or sound to
convey a particular idea.”); id. at xxviii (“We seek to restore sound interpretive conventions.”). See also Nelson, supra
note 101, at 377, 383 (arguing textualists prefer the canons to legislative history because of their more rule-like nature);
William N. Eskridge, Jr., The New Textualism, 37 UCLA L. REV. 621, 663 (1990) (“The new textualists . . . seek a
revival of canons that rest upon precepts of grammar and logic, proceduralism, and federalism. The Court’s opinions in
the last two Terms reflect this revival urged by the new textualists.”).
367 Nelson, supra note 101, at 383. Nelson prefers these categories to the traditional distinction between semantic and
substantive canons. See id. at 394 n.140. Cf. Cass R. Sunstein, Interpreting Statutes in the Regulatory State, 103 HARV.
L. REV. 405, 454 (1989) (noting canons “have served different functions” and distinguishing widely shared and
uncontroversial “invisible norms” from “background norms” that “more visibly serve substantive or institutional
goals,” but recognizing that “the distinction . . . is imprecise”).
368 Nelson, supra note 101, at 383.
369 Id.
370 Id. at 383–84.
371 Id. at 384.
372 Id.
373 See id. at 390 (“Many of the canons used by textualists reflect observations about Congress’s own habits.”).
374 See Scalia, supra note 84, at 29 (“The rule of lenity is almost as old as the common law itself, so I suppose that is
validated by sheer antiquity.”). See also, e.g., United States v. Wiltberger, 18 U.S. (5 Wheat.) 76, 95 (1820) (“The rule
that penal laws are to be construed strictly, is perhaps not much less old than construction itself.”).
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canons reflect good policy,375 or because they believe the canons provide principles that limit
judicial deference376 and promote predictability in judicial decisionmaking.377
Defenders of the canons have argued that they help judges act as faithful agents of the legislature,
either because they reflect legislative drafting practices or because they provide coordinating
background rules that can guide Congress when drafting legislation.378 For example, the
constitutional-avoidance canon is frequently said to respect legislative supremacy379—although
judges do not always agree on the reasons why.380 The Court has, at times, said that the
constitutional-avoidance canon reflects what Congress meant because Congress would not have
wanted to enact an unconstitutional statute.381 Choosing a reasonable alternative interpretation
“recognizes that Congress, like [the courts], is bound by and swears an oath to uphold the
Constitution.”382 Others have argued that even if the canon does not reflect actual congressional
practice, it properly represents a judicial policy judgment “that courts should minimize the
occasions on which they confront and perhaps contradict the legislative branch.”383
Some judges, however—primarily purposivists—have argued for greater caution in deploying the
canons of construction, warning that insofar as they do not reflect the reality of legislative

375 See, e.g., Stephen F. Ross, Where Have You Gone, Karl Llewellyn? Should Congress Turn Its Lonely Eyes to You?,
45 VAND. L. REV. 561, 563 (1992) (“[N]ormative canons are principles . . . that . . . direct courts to construe any
ambiguity in a particular way in order to further some policy objective.”). See also William N. Eskridge, Jr., Public
Values in Statutory Interpretation
, 137 U. PA. L. REV. 1007, 1018 (1989) (arguing interpreters should explicitly
incorporate “rational background understandings,” or “underlying public values” into application of the canons of
construction); Sunstein, supra note 367, at 413 (arguing some substantive canons can and should “be supported through
an understanding of the ways in which they incorporate constitutional principles, promote deliberation in government,
and respond to New Deal reforms of the legal system”).
376 See, e.g., Posner, Statutory Interpretation—in the Classroom and in the Courtroom, supra note 125, at 807 (“A . . .
line of defense is that even if the canons do not make very good sense, it is better that the judges should feel
constrained by some interpretive rules than free to roam at large in a forest of difficult interpretive questions . . . .”).
377 See, e.g., Nelson, supra note 101, at 391 (“[C]anons and presumptions can . . . take advantage of . . . relative
predictability. . . . [S]ome specialized canons help courts discern Congress’s likely intent . . . simply because members
of Congress know that the courts use them. That knowledge . . . enables members of Congress to convey their intended
meaning in a way that the courts will understand.”). See also Eskridge & Frickey, Law As Equilibrium, supra note 295,
at 67 (“[T]he canons may be understood as conventions, similar to driving a car on the right-hand side of the road;
often it is not as important to choose the best convention as it is to choose one convention, and stick to it.”).
378 Christopher J. Walker, Inside Agency Statutory Interpretation, 67 STAN. L. REV. 999, 1021 (2015); HART & SACKS,
supra note 17, at 1376; see also, e.g., Morrison v. Nat’l Austl. Bank Ltd., 561 U.S. 247, 261 (2010) (noting that
consistent application of presumption against extraterritoriality creates “a stable background against which Congress
can legislate with predictable effects”). But see Abbe R. Gluck, Congress, Statutory Interpretation, and the Failure of
Formalism: The CBO Canon and Other Ways That Courts Can Improve on What They Are Already Trying to Do
, 84 U.
CHI. L. REV. 177, 179 (2017) (arguing that the system-coordinating justification for a formalist approach employing the
canons is untenable).
379 See, e.g., William K. Kelley, Avoiding Constitutional Questions as a Three-Branch Problem, 86 CORNELL L. REV.
831, 843 (2001). But see, e.g., Frank H. Easterbrook, Do Liberals and Conservatives Differ in Judicial Activism?, 73 U.
COLO. L. REV. 1401, 1405 (2002) (arguing the canon of constitutional avoidance is “wholly illegitimate” because it
“acts as a roving commission to rewrite statutes to taste”).
380 See, e.g., MANNING & STEPHENSON, supra note 299, at 260–61. Others argue that even if the constitutional-
avoidance canon does not advance legislative supremacy, it may be useful to protect constitutional values, by allowing
courts to impose narrowing constructions on constitutionally dubious statutes. See ESKRIDGE ET AL., supra note 40, at
365.
381 See, e.g., Yates v. United States, 354 U.S. 298, 319 (1957) (“[W]e should not assume that Congress chose to
disregard a constitutional danger zone so clearly marked.”).
382 Edward J. DeBartolo Corp. v. Fla. Gulf Coast Bldg. & Constr. Trades Council, 485 U.S. 568, 575 (1988).
383 SCALIA & GARNER, supra note 24, at 249.
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drafting, they may not respect legislative supremacy.384 Supporting this concern, some empirical
studies have raised questions as to whether some of these canons do in fact reflect how ordinary
English speakers or legislatures use words.385 One widely discussed article, published in 2013,
surveyed 137 congressional staffers to assess whether legislative staffers were aware of various
judicial doctrines of statutory interpretation and whether the drafters actually complied with those
doctrines.386 Their findings demonstrated a wide range of awareness and use of various semantic
and substantive canons, and suggested that some canons, such as the surplusage canon, are not
widely used by Congress.387 However, some have pointed out that this study may not provide a
complete view of the federal lawmaking process388—and the authors themselves recognized many
of the limitations in their study.389
Responding to this study, then-professor (now Justice) Barrett explained that textualists would
likely reject this legislative “process-based” approach to evaluating the canons because textualists
do not use canons “in an effort to track the linguistic patterns of the governors; they use them
because they reflect the linguistic patterns of the governed.”390 In response to this criticism,
another group of scholars surveyed “4,500 demographically representative people recruited from
the United States, as well as a sample of over one-hundred first-year U.S. law students” to test
their knowledge of the canons.391 The study found that while non-governmental speakers do
frequently read laws in accordance with many of the canons tested, some of them are less
frequently applied.392 A number of judges have cited the initial study on congressional drafting
practices in explaining their choices about whether to apply certain canons;393 it remains to be
seen whether this second survey will be as influential.
Even if a judge agrees that a particular canon is generally valid, the court may still doubt that it
should control the interpretation of a particular statute. Modern theory acknowledges that the
application of a particular canon in any case is highly context-dependent.394 The canons merely
supply “one indication” of meaning,395 suggesting only that “a particular meaning is linguistically

384 See, e.g., KATZMANN, supra note 111, at 52 (“[W]iping out legislative history, in the face of empirical evidence that
Congress views it as essential in understanding its meaning, leaves us largely with a canon-based interpretive regime
that may not only fail to reflect the reality of the legislative process, but may also undermine the constitutional
understanding that Congress’s statutemaking should be respected as a democratic principle.”). See also Breyer, supra
note 32, at 870 (arguing legislative history is more accessible than the canons to give notice of statutory meaning).
385 See, e.g., Tobia et al., supra note 207, at 249–62, 271; Gluck & Bressman, supra note 204, at 907.
386 Gluck & Bressman, supra note 204, at 920.
387 Id. at 949.
388 See, e.g., Kysar, supra note 116, at 1118–19; Jarrod Shobe, Intertemporal Statutory Interpretation and the Evolution
of Legislative Drafting
, 114 COLUM. L. REV. 807, 810–11, 837, 863–65 (2014).
389 See Gluck & Bressman, supra note 204, at 922–23 (noting limitations in survey sample); 1020–21 (noting
possibility that collective or outside knowledge may impact drafting process).
390 Barrett, supra note 136, at 2194.
391 Tobia et al., supra note 207, at 225.
392 Id. at 249–62.
393 See, e.g., Yates v. United States, 574 U.S. 528, 562 (2015) (Kagan, J., dissenting); United States v. Koutsostamatis,
956 F.3d 301, 307 n.1 (5th Cir. 2020); Zarda v. Altitude Express, Inc., 883 F.3d 100, 130 (2d Cir. 2018); Loving v.
IRS, 742 F.3d 1013, 1019 (D.C. Cir. 2014).
394 See, e.g., HART & SACKS, supra note 17, at 1191 (“Of course there are pairs of maxims susceptible of being invoked
for opposing conclusions. Once it is understood that meaning depends on context, and that contexts vary, how could it
be otherwise?”).
395 Scalia, supra note 84, at 27 (“Every canon is simply one indication of meaning; and if there are more contrary
indications (perhaps supported by other canons), it must yield.”). See, e.g., Rice v. Rehner, 463 U.S. 713, 732 (1983)
(“[W]e have consistently refused to apply . . . a canon of construction when application would be tantamount to a
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permissible, if the context warrants it.”396 Judges sometimes describe the canons as akin to
rebuttable presumptions.397 Judges will weigh application of the canon against the evidence of
statutory meaning discovered through other interpretive tools and may disagree about whether a
canon is so contrary to other indicators of meaning that it should not be applied.398 The use of the
canons “rest[s] on reasoning,” and their application should be justified in any given case.399
A judge’s willingness to deploy a particular canon, generally or in a specific case, may also
depend on that judge’s particular theory of interpretation. Many judges will turn to the canons
only if more favored tools fail to resolve any ambiguity.400 For example, Justice Clarence
Thomas, who is generally described as a textualist,401 stated the following in one Supreme Court
opinion:
[C]anons of construction are no more than rules of thumb that help courts determine the
meaning of legislation, and in interpreting a statute a court should always turn first to one,
cardinal canon before all others. We have stated time and again that courts must presume
that a legislature says in a statute what it means and means in a statute what it says there.402
Acccordingly, in that opinion, Justice Thomas concluded that because the statutory text was clear,
the canon against surplusage was inapplicable.403
In a similar vein, Justice William Brennan argued that it was unnecessary to invoke the canon of
constitutional avoidance in his dissenting opinion in NLRB v. Catholic Bishop of Chicago.404 In
particular, he contended that the alternative reading adopted by the majority was not a “fairly
possible” interpretation of the statute, relying heavily on the statute’s legislative history to
demonstrate that Congress intended to foreclose the majority opinion’s construction.405 Thus,
although a particular canon might facially operate to resolve a particular statutory ambiguity,
judges may disagree about whether a canon’s application is appropriate, if another interpretive

formalistic disregard of congressional intent. . . . In the present case, congressional intent is clear from the face of the
statute and its legislative history.”).
396 HART & SACKS, supra note 17, at 1191. See also, e.g., Yellen v. Confederated Tribes of the Chehalis Reservation,
141 S. Ct. 2434, 2448 (2021) (noting that canons must give way if they yield a “contextually implausible outcome,”
because “[t]he most grammatical reading of a sentence in a vacuum does not always produce the best reading in
context” (quoting Facebook, Inc. v. Duguid, 141 S. Ct. 1163, 1171 (2021)) (internal quotation marks omitted)).
397 See, e.g., District of Columbia v. Thompson, 593 A.2d 621, 631 (D.C. 1991). See also, e.g., Frank H. Easterbrook,
The Absence of Method in Statutory Interpretation, 84 U. CHI. L. REV. 81, 83 (2017) (noting that “every canon
implicitly begins or ends with the statement ‘unless the context indicates otherwise’”).
398 See, e.g., Lockhart v. United States, 577 U.S. 347, 352 (2016) (arguing rule of last antecedent applies and “is not
overcome by other indicia of meaning”); id. at 363 (Kagan, J., dissenting) (arguing statutory context shows rule of last
antecedent does not apply to the disputed provision).
399 Sinclair, supra note 289, at 992. See also Varity Corp. v. Howe, 516 U.S. 489, 511 (1996) (“To apply a canon
properly one must understand its rationale.”).
400 See, e.g., Richlin Sec. Serv. Co. v. Chertoff, 553 U.S. 571, 589–90 (2008) (“[W]e have never held that [a particular
canon] displaces the other traditional tools of statutory construction. . . . In this case, traditional tools of statutory
construction and considerations of stare decisis compel [a certain] conclusion . . . . There is no need for us to resort to
the . . . canon because there is no ambiguity left for us to construe.”).
401 See, e.g., Fallon, Three Symmetries, supra note 216 at 691 (describing Justice Thomas as “a recognized textualist”).
402 Conn. Nat’l Bank v. Germain, 503 U.S. 249, 253–54 (1992).
403 Id. Two concurring opinions in that case argued that the Court should have also considered the statute’s legislative
history, id. at 255 (Stevens, J., concurring), and should have acknowledged that this interpretation did violate the canon
against surplusage and explained why the canon did not control, id. at 256 (O’Connor, J., concurring).
404 NLRB v. Catholic Bishop of Chi., 440 U.S. 490, 511 (1979) (Brennan, J., dissenting).
405 Id. at 511–15.
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tool suggests the statute should bear another meaning and if a particular jurisprudential
methodology counsels for reliance on that particular tool.406
Legislative History
Where the text of the statute alone does not answer the relevant question, judges have at times
turned to a statute’s legislative history,407 defined as the record of Congress’s deliberations when
enacting a law.408 One of the Supreme Court’s most famous—and perhaps infamous—invocations
of legislative history came in United Steelworkers v. Weber.409 In that case, the Court considered
whether Title VII of the Civil Rights Act of 1964, which “make[s] it unlawful to
‘discriminate . . . because of . . . race’ in hiring” and training employees, prohibited a private
employer from adopting an affirmative action plan intended to increase the number of black
employees in one of its training programs.410 The Court noted that “a literal interpretation” of the
relevant statutory provisions arguably would forbid such plans, since they “discriminate[d]
against white employees solely because they [were] white.”411 Nonetheless, the Court concluded
that in this case, such a “literal construction” was “misplaced.”412 Instead, writing for the
majority, Justice Brennan used the legislative history of Title VII to uncover evidence of the
statute’s purpose, examining a number of statements from individual Senators as well as the
committee report.413 He concluded that the law sought to “address centuries of racial injustice,”
and Congress could not have “intended to prohibit the private sector from taking effective steps to
accomplish the goal that Congress designed Title VII to achieve.”414 In Justice Brennan’s view,
the private employer’s plan mirrored the purposes of the statute415 by seeking “to abolish

406 See, e.g., Grand Trunk W. R.R. Co. v. U.S. Dep’t of Labor, 875 F.3d 821, 825 (2017) (concluding statutory context
overcomes presumption of “so-called Russello structural canon”—that “‘[w]here Congress includes particular language
in one section of a statute but omits it in another section of the same Act, it is generally presumed that Congress acts
intentionally and purposely in the disparate inclusion or exclusion’” (alteration in original) (quoting Russello v. United
States, 464 U.S. 16, 23 (1983))).
407 See, e.g., Mitchell v. Cohen, 333 U.S. 411, 418 (1948).
408 ESKRIDGE ET AL., supra note 40, at 303. This report addresses only pre-enactment legislative history, and does not
discuss the even more contentious category of post-enactment legislative history. See, e.g., ESKRIDGE ET AL., supra note
40, at 316 (discussing “subsequent legislative history,” or congressional statements and actions related to a law after its
enactment, such as when Congress rejects amendments to a law). The report addresses separately other post-enactment
interpretive tools infra “Statutory Implementation.See also HART & SACKS, supra note 17, at 1255–70 (reviewing
“post-enactment aids to interpretation,” including popular construction, administrative construction, judicial
construction, and legislative silence or acquiescence).
409 United Steelworkers of Am., AFL-CIO-CLC v. Weber, 443 U.S. 193, 201 (1979). Cf., e.g., SCALIA & GARNER,
supra note 24, at 12 (arguing this case’s reading of the statute “def[ies] the text”); Eskridge & Frickey, Statutory
Interpretation as Practical Reasoning
, supra note 169, at 336 (arguing this case was decided “by romanticizing the
legislative process and subordinating other purposes of Title VII”).
410 United Steelworkers, 443 U.S. at 201 (quoting 42 U.S.C. § 2000-e(2)(a), (d)).
411 Id.
412 Id.
413 Id. at 202–07.
414 Id. at 204. See also id. at 207 (“Congress did not intend to limit traditional business freedom to such a degree as to
prohibit all voluntary, race-conscious affirmative action.”).
415 Id. at 208.
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traditional patterns of racial segregation and hierarchy,”416 and the legislative history
demonstrated that Congress intended to leave an “area of discretion” for just such a plan.417
Purposes for Using Legislative History
The use of legislative history has generated significant debate over the past century.418 In its most
controversial applications, legislative history has been deployed in opinions that cite a statute’s
purpose to override arguably clear text, as demonstrated by Weber.419 Most frequently, however,
when modern judges use legislative history, it is not to contradict a clear text but to discover
evidence of an ambiguous statute’s underlying purpose or confirm a reading suggested by other
tools.420 As with the substantive canons, courts have suggested that legislative history should not
be examined unless the statutory text is ambiguous.421 Of course, judges may disagree whether
the text is sufficiently ambiguous to warrant recourse to a statute’s legislative history.422 Judges
have also used legislative history to support a textual interpretation.423 An increasingly common
phrasing in Supreme Court majority opinions discusses legislative history as additional support
for “those who consider” it.424
Judges do not always use legislative history to determine a statute’s purpose.425 Even textualist
judges may use legislative history to determine whether a statutory term has a specialized
meaning426 or to determine whether a seemingly incongruous result nonetheless aligns with

416 Id. at 204.
417 Id. at 209.
418 E.g., MANNING & STEPHENSON, supra note 299, at 127. See also id. at 127–28 (outlining historical trends in use of
legislative history in U.S. courts, beginning with a rule of general exclusion, swinging towards general inclusion around
1940, and describing the new backlash against its use beginning in the 1980s).
419 See Weber, 443 U.S. at 201–02. See also, e.g., Church of the Holy Trinity v. United States, 143 U.S. 457, 464–65
(1892).
420 See, e.g., Milner v. Dep’t of the Navy, 562 U.S. 562, 572 (2011) (“Those of us who make use of legislative history
believe that clear evidence of congressional intent may illuminate ambiguous text. We will not take the opposite tack of
allowing ambiguous legislative history to muddy clear statutory language.”). See also, e.g., HART & SACKS, supra note
17, at 1379 (“Effect should not be given to evidence from the internal legislative history if the result would be to
contradict a purpose otherwise indicated . . . .”).
421 See, e.g., Green v. Bock Laundry Mach. Co., 490 U.S. 504, 508–09 (1989).
422 Compare, e.g., Arlington Cent. Sch. Dist. Bd. of Educ. v. Murphy, 548 U.S. 291, 304 (2006) (disregarding
legislative history where statutory text was unambiguous), with id. at 323 (Breyer, J., dissenting) (arguing statutory text
was ambiguous and turning to legislative history). Then-Judge Brett Kavanaugh argued that “the indeterminacy of the
trigger”—that is, determining when the text is ambiguous— “greatly exacerbates the problems with the use of
legislative history.” Kavanaugh, supra note 131, at 2149.
423 See, e.g., Milavetz, Gallop & Milavetz, P. A. v. United States, 559 U.S. 229, 236 n.3 (2010) (“Although reliance on
legislative history is unnecessary in light of the statute’s unambiguous language, we note the support that record
provides for the Government’s reading.”). But see, e.g., Dig. Realty Tr., Inc. v. Somers, 138 S. Ct. 767, 783–84 (2018)
(Thomas, J., concurring) (arguing majority opinion should not have relied on committee report “to discuss the supposed
‘purpose’ of the statute”).
424 E.g., Unicolors, Inc. v. H&M Hennes & Mauritz, L.P., 142 S. Ct. 941, 946–48 (2022) (discussing the text and
statutory context before turning to legislative history as additional “persuasive” support for “those who consider” it);
Guerrero-Lasprilla v. Barr, 140 S. Ct. 1062, 1072 (2020) (similar); Sturgeon v. Frost, 139 S. Ct. 1066, 1085 (2019)
(similar).
425 See, e.g., Breyer, supra note 32, at 848.
426 See, e.g., Pierce v. Underwood, 487 U.S. 552, 563–64 (1988) (relying on “a Committee Report prepared at the time
of the original enactment of” the disputed statute to define the phrase “substantially justified,” as used in the disputed
statute to describe a party’s litigating position). See also, e.g., SCALIA & GARNER, supra note 24, at 388 (“[F]or the
purpose of establishing linguistic usage—showing that a particular word or phrase is capable of bearing a particular
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congressional intent.427 Some judges may also use legislative history to determine the scope of a
statute and ascertain whether Congress sought to address the particular problem before the court
at all.428 Thus, for example, in FDA v. Brown & Williamson Tobacco Corp., the Court reviewed
the history of various “tobacco-specific legislation that Congress ha[d] enacted over the past 35
years,” along with the history of the disputed provision located in the agency’s organic statute,
the Federal Food, Drug, and Cosmetic Act (FDC&A).429 In the Court’s view, the fact that the
other legislative acts specifically concerned the issue of tobacco bore directly on the meaning of
the FDC&A, which did not expressly address tobacco.430 The Court concluded that Congress did
not intend to give the FDA jurisdiction to broadly regulate tobacco products in the FDC&A.431
The Debate over Using Legislative History
To the extent that legislative history is used to determine statutory purpose, purposivists and
textualists may disagree about whether legislative history is a permissible tool of statutory
interpretation.432 Many purposivists defend the use of legislative history on the grounds that these
deliberative materials can illuminate the context and purpose of a statutory provision.433
Purposivists emphasize legislative process,434 and legislative history provides a record of that
process.435 Defenders of legislative history generally argue that in statutory interpretation, judges
should respect the processes Congress has established and should pay attention to those materials
that Congress itself has used to memorialize the lawmaking process.436 This is particularly true,
argue some, because Congress generally does place significance on at least certain types of
legislative history.437 Thus, the central argument in favor of the use of legislative history is
grounded in the purposivist view of legislative supremacy.438

meaning—it is no more forbidden (though no more persuasive) to quote a statement from the floor debate on the statute
in question than it is to quote the Wall Street Journal or the Oxford English Dictionary.”).
427 See, e.g., Green v. Bock Laundry Mach. Co., 490 U.S. 504, 527 (1989) (Scalia, J., concurring) (arguing that it is
“entirely appropriate to consult all public materials, including the background of [the disputed provision] and the
legislative history of its adoption, to verify that what seems to us an unthinkable disposition . . . was indeed unthought
of, and thus to justify a departure from the ordinary meaning [of the disputed term]”). See also, e.g., SCALIA & GARNER,
supra note 24, at 388 (“[L]egislative history can be consulted to refute attempted application of the absurdity
doctrine—to establish that it is indeed thinkable that a particular word or phrase should mean precisely what it says.”).
Similarly, courts may—in rare cases—use legislative history to determine that Congress made a mistake. See, e.g., U.S.
Nat’l Bank v. Indep. Ins. Agents of Am., 508 U.S. 439, 462 (1993) (“In these unusual cases, we are convinced that the
placement of the quotation marks in the 1916 Act was a simple scrivener’s error, a mistake made by someone
unfamiliar with the law’s object and design.”).
428 See Easterbrook, What Does Legislative History Tell Us?, supra note 146, at 443.
429 FDA v. Brown & Williamson Tobacco Corp., 529 U.S. 120, 143–56 (2000).
430 Id. at 143.
431 Id. at 142.
432 See, e.g., Manning, What Divides Textualists from Purposivists?, supra note 23, at 84, 90.
433 Breyer, supra note 32, at 848.
434 E.g., KATZMANN, supra note 111, at 31 (“[L]egislation is the product of a deliberative and informed process. Statutes
in this conception have purposes or objectives that are discernible. The task of the judge is to make sense of legislation
in a way that is faithful to Congress’s purposes.”).
435 E.g., id. at 29.
436 E.g., Breyer, supra note 32, at 858–60.
437 E.g., Gluck & Bressman, supra note 204, at 967; Jesse M. Cross & Abbe R. Gluck, The Congressional
Bureaucracy
, 168 U. PA. L. REV. 1541, 1549 (2020).
438 E.g., KATZMANN, supra note 111, at 4 (“Our constitutional system charges Congress, the people’s branch of
representatives, with enacting laws. So, how Congress makes its purposes known, through text and reliable
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By contrast, many textualists argue that legislative history should be used sparingly.439 The first
and perhaps most persistent objection is theoretical: Justice Scalia, for example, argued the use of
legislative history improperly “assumes that what [judges] are looking for is the intent of the
legislature rather than the meaning of the statutory text.”440 Accordingly, to the extent legislative
history enables a judge to elevate a judgment about “background purposes” above “the clear
import of an enacted text,” textualists disagree with the use of this tool.441 Textualists frequently
claim that using legislative history in this way is inappropriate because “as a formal matter,” it is
this text, and not the “committee reports and floor statements,” that are “the law enacted by
Congress.”442 Textualists’ primary objections to legislative history are therefore rooted in their
own distinct view of how courts best observe legislative supremacy.443
Many textualists also harbor more practical concerns about the reliability of legislative history.444
Justice Scalia frequently argued that “[e]ven if legislative intent did exist, there would be little
reason to think it might be found in the sources that the courts consult.”445 In his view, even
committee reports do not necessarily represent the understanding of the full Congress, given that
they are created by a minority of Members, making it dangerous to draw assumptions about the
whole body’s understanding of the statute from such documents.446 Justice Scalia also warned
that legislative history is subject to intentional manipulation and gamesmanship, making it even
less likely that these documents reflect legislative intent.447 Finally, judges have pointed out that
due to the multiplicity of actors, “legislative history is often conflicting,” making it difficult to
determine which parts of the record should be heeded.448 Judge Harold Leventhal once observed
that using legislative history can be like “looking over a crowd and picking out your friends.”449

accompanying materials constituting legislative history, should be respected, lest the integrity of legislation be
undermined.”). See generally Manning, Legal Realism & the Canons’ Revival, supra note 176, at 288–89 (“Legislative
history [in the view of purposivists] . . . might serve the same function as the canons (eliminating ambiguity), but with
the distinct advantage of having a more democratic pedigree.”). This justification for using legislative history appeals
beyond purposivists to at least some pragmatists. See, e.g., ESKRIDGE ET AL., supra note 40, at 239.
439 See, e.g., Nelson, supra note 101, at 361.
440 SCALIA & GARNER, supra note 24, at 375. See also Conroy v. Aniskoff, 507 U.S. 511, 519 (1993) (Scalia, J.,
concurring) (“The greatest defect of legislative history is its illegitimacy. We are governed by laws, not by the
intentions of legislators.”). This concern rests on the “intent skepticism” shared by both textualists and purposivists.
Manning, Inside Congress’s Mind, supra note 31, at 1912–13.
441 Manning, What Divides Textualists from Purposivists?, supra note 23, at 73.
442 Kavanaugh, supra note 131, at 2149. See also, e.g., NLRB v. SW Gen., Inc., 137 S. Ct. 929, 942 (2017) (“What
Congress ultimately agrees on is the text that it enacts, not the preferences expressed by certain legislators.”); City of
Chicago v. Envtl. Def. Fund, 511 U.S. 328, 337 (1994) (“[I]t is the statute, and not the Committee Report, which is the
authoritative expression of the law . . . .”).
443 See, e.g., MANNING & STEPHENSON, supra note 299, at 151–53; Lawson v. FMR LLC, 571 U.S. 429, 459–60 (2014)
(Scalia, J., concurring) (arguing against using legislative history to discover congressional intent because “we are a
government of laws, not of men, and are governed by what Congress enacted rather than by what it intended”).
444 See, e.g., MANNING & STEPHENSON, supra note 299, at 158.
445 E.g., SCALIA & GARNER, supra note 24, at 376.
446 Wis. Pub. Intervenor v. Mortier, 501 U.S. 597, 620–21 (1991) (Scalia, J., concurring).
447 See, e.g., SCALIA & GARNER, supra note 24, at 376–77. See also, e.g., Circuit City Stores v. Adams, 532 U.S. 105,
120 (2001) (“We ought not attribute to Congress an official purpose based on the motives of a particular group that
lobbied for or against a certain proposal . . . .”).
448 Kavanaugh, supra note 131, at 2149. See also, e.g., Conroy v. Aniskoff, 507 U.S. 511, 519–20 (1993) (Scalia, J.,
concurring) (arguing legislative history is indeterminate).
449 Patricia M. Wald, Some Observations on the Use of Legislative History in the 1981 Supreme Court Term, 68 IOWA
L. REV. 195, 214 (1983).
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These concerns about the reliability of legislative history may apply whether the tool is used to
discover a statute’s purpose or for another reason.
In light of these criticisms, many judges who see value in examining legislative history to discern
the legislature’s intent have used such materials in more nuanced ways.450 Courts review
legislative history in light of the text ultimately enacted,451 and in conjunction with other
interpretive tools.452 Many judges also view some types of legislative history as more reliable
than others, drawing from their understanding of congressional procedure.453 Justice Sotomayor,
for example, has written that committee reports “are a particularly reliable source” of legislative
history because they are circulated with a bill to Members and their staff, and are viewed by those
people as reliable indicators of the bill’s meaning.454 By contrast, the Court has noted that floor
debates are a weaker form of legislative history because they “reflect at best the understanding of
individual Congressmen.”455

450 See, e.g., Exxon Mobil Corp. v. Allapattah Servs., Inc., 545 U.S. 546, 568 (2005); see also, e.g., Victoria F. Nourse,
A Decision Theory of Statutory Interpretation: Legislative History by the Rules, 122 YALE L.J. 70, 78 (2012) (arguing
courts must view legislative history with a better understanding of congressional procedures). Cf. KATZMANN, supra
note 111, at 46 (noting that in response to textualist critiques of legislative history, judges “tend to give it more of a
supporting rather than a leading role in statutory interpretation”); Gluck & Posner, supra note 169, at 1326 (noting that
none of the judges in their survey use legislative history “indiscriminately”).
451 See, e.g., NLRB v. SW Gen., Inc., 137 S. Ct. 929, 942–43 (2017).
452 See, e.g., Wyeth v. Levine, 555 U.S. 555, 566–68 (2009) (looking to legislative history to determine whether
Congress intended to overcome presumption embodied in substantive canon); Howard Delivery Serv., Inc. v. Zurich
Am. Ins. Co., 547 U.S. 651, 658–59 (2006) (looking to legislative history, including drafting history and committee
reports, to determine the purpose of the disputed provision, and reviewing this purpose in light of the statutory context).
453 See, e.g., Schwegmann Bros. v. Calvert Distillers Corp., 341 U.S. 384, 395–96 (1951) (Jackson, J., concurring)
(“Resort to legislative history is only justified where the face of the Act is inescapably ambiguous, and then I think we
should not go beyond Committee reports, which presumably are well considered and carefully prepared. . . . [T]o select
casual statements from floor debates, not always distinguished for candor or accuracy, as a basis for making up our
minds what law Congress intended to enact is to substitute ourselves for the Congress in one of its important
functions.”).
454 Dig. Realty Tr., Inc. v. Somers, 138 S. Ct. 767, 782 (2018) (Sotomayor, J., concurring). See also George A.
Costello, Average Voting Members and Other “Benign Fictions”: The Relative Reliability of Committee Reports, Floor
Debates, and Other Sources of Legislative History
, 1990 DUKE L.J. 39, 43 (1990) (noting committee reports are
“ordinarily . . . considered the most reliable and persuasive element of legislative history” by the Supreme Court).
455 Zuber v. Allen, 396 U.S. 168, 186 (1969) (“A committee report represents the considered and collective
understanding of those Congressmen involved in drafting and studying proposed legislation. Floor debates reflect at
best the understanding of individual Congressmen. It would take extensive and thoughtful debate to detract from the
plain thrust of a committee report in this instance.”). See also, e.g., Food Mktg. Inst. v. Argus Leader Media, 139 S. Ct.
2356, 2364 (2019) (describing witness statements from congressional hearings on a different bill as particularly
unhelpful, especially given that the statements contradicted official committee reports).
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One group of legal scholars created a
hierarchy of legislative history derived from
federal case law, shown in Figure 1.456 One
Figure 1. Hierarchy of Legislative History
2020 article provided some empirical
insight into legislative history hierarchy by
conducting interviews with 30
congressional staffers.457 That study
suggested courts should view legislative
history, “in order of decreasing reliability,
as follows: (1) [c]ommittee reports; (2) [a]ll
statements by a Chair or Ranking Member
of a committee or subcommittee on a topic
within committee or subcommittee
jurisdiction; (3) [o]ther markup and hearing
statements; (4) [o]ther floor statements.”458
The preceding discussion does not account
for a special form of legislative history—a
history of amendment. Courts will generally
accord significant weight to Congress’s
changes to a prior statute in a subsequent
statute.459 Like the other forms of legislative
history discussed in this report, legislative
action amending a statute provides a record

of congressional deliberation prior to the
enactment of the disputed statute.
Source: E
460
SKRIDGE ET AL., supra note 40, at 317.
However, unlike the other forms of legislative history, a prior version of a statute is itself formally
enacted, and to many, therefore provides stronger evidence of a statute’s evolution. The Supreme
Court has said, “When Congress acts to amend a statute, we presume it intends its amendment to
have real and substantial effect.”461 As a result, a statute’s amendment history can even overcome
other evidence of statutory meaning.462

456 ESKRIDGE ET AL., supra note 40, at 317. See also KATZMANN, supra note 111, at 54 (arguing “conference committee
reports and committee reports” should be considered most authoritative, “followed by statements of the bill’s managers
in the Congressional Record, with stray statements of legislators on the floor—who had heretofore not been involved in
consideration of the bill—at the bottom”).
457 Cross, supra note 205, at 95.
458 Id. at 97.
459 See, e.g., Lomax v. Ortiz-Marquez, 140 S. Ct. 1721, 1726–27 (2020) (concluding that the purpose of a law was to go
beyond existing provisions regulating the same topic, and rejecting an interpretation that would have made the new law
coextensive with prior coverage); United States v. Brown, 333 U.S. 18, 25 (1948) (concluding amendment of disputed
provision “was intended . . . to broaden the Act’s coverage or to assure its broad coverage”).
460 See supra note 408 and accompanying text.
461 Stone v. INS, 514 U.S. 386, 397 (1995). See also, e.g., Ross v. Blake, 578 U.S. 632, 640–41 (2016) (concluding
mandatory nature of disputed provision was affirmed by its history, where it replaced a weaker precursor). In
comparison, one Supreme Court opinion described as “noteworthy” a Senate vote approving a joint resolution that, if
enacted into law, would have disapproved a particular agency interpretation of the disputed statute. Nat’l Fed’n of
Indep. Bus. v. OSHA, 142 S. Ct. 661, 666 (2022).
462 See, e.g., Pierce Cty. v. Guillen, 537 U.S. 129, 145 (2003) (concluding substantive canon should not apply because
that canon “would render the 1995 amendment to [the disputed provision] . . . an exercise in futility”).
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Statutory Implementation
Finally, courts frequently investigate how a statute actually works, asking what problem Congress
sought to address by enacting the disputed provision, and how Congress went about doing that.463
As a result, courts have assessed whether the consequences of an asserted interpretation align
with the statutory scheme.464 A focus on practical consequences is, at least academically,
sometimes aligned with the so-called dynamic theories of interpretation and, when viewed as
such, is generally disfavored.465 Nonetheless, scholars have maintained that “practical
considerations play an important role in the [Supreme] Court’s statutory cases,”466 as discussed in
more detail below. Further, judges may look to the consequences of a particular meaning as part
of a broader inquiry that primarily focuses on the text.467 Courts sometimes look for evidence of
practical consequences in materials from the agencies that are charged with implementing the
disputed statute, but they also rely on their own understandings of how the statute works.
Agency Interpretations
Administrative agencies are frequently the first official interpreters of statutes: in the course of
implementing a statutory scheme, interpretive questions arise and must be resolved in order for
the agency to do its work. When courts interpret a statute, they sometimes consider these agency
interpretations, whether the agency’s views are asserted through administrative rulings or a
pattern of action.468 A judge might cite an agency’s unofficial but public interpretation of a
statutory term to support other evidence justifying a particular interpretation.469 Alternatively, a
judge might use evidence of the way an administrative agency has implemented a statute to gain a
sense of the problem that Congress sought to address and how the statutory scheme generally
works to address that problem.470

463 See, e.g., Nixon v. Mo. Mun. League, 541 U.S. 125, 132–33 (2004) (“[C]oncentration on the writing on the page
does not produce a persuasive answer here. . . . [I]n this litigation it helps if we ask how Congress could have
envisioned the preemption clause actually working if the FCC applied it at the municipal respondents’ urging.”).
464 See, e.g., Schwegmann Bros. v. Calvert Distillers Corp., 341 U.S. 384, 389 (1951) (rejecting interpretation under
which “the exception swallows the proviso and destroys its practical effectiveness”).
465 See supra notes 89 to 94 and accompanying text (discussing dynamic theories of interpretation). See also, e.g., BP
p.l.c. v. Mayor of Baltimore, 141 S. Ct. 1532, 1542 (2021) (“[T]his Court’s task is to discern and apply the law’s plain
meaning as faithfully as we can, not ‘to assess the consequences of each approach and adopt the one that produces the
least mischief.’” (quoting Lewis v. Chicago, 560 U.S. 205, 217 (2010))).
466 Nicholas S. Zeppos, The Use of Authority in Statutory Interpretation: An Empirical Analysis, 70 TEX. L. REV. 1073,
1107 (1992). This finding was confirmed in more recent empirical studies of Supreme Court cases. See Krishnakumar,
Statutory Interpretation in the Roberts Court’s First Era, supra note 216, at 225–26 (suggesting there are two camps of
Justices that use practical consequences in distinct ways); Krishnakumar, Reconsidering Substantive Canons, supra
note 199, at 887 (noting empirical evidence that the Supreme Court frequently uses practical consequences to interpret
statutes).
467 See, e.g., RJR Nabisco, Inc. v. European Cmty., 579 U.S. 325, 344 (2016) (“The practical problems we have
identified with [the defendant’s reading of the statute] are not, by themselves, cause to reject it. Our point in reciting
these troubling consequences of [the defendant’s] theory is simply to reinforce our conclusion, based on [the disputed
statute’s] text and context . . . .”).
468 See, e.g., FCC v. Am. Broad. Co., 347 U.S. 284, 294–95 (1954).
469 See, e.g., id.; S.D. Warren Co. v. Me. Bd. of Envtl Prot., 547 U.S. 370, 377 (2006) (citing the EPA’s Water Quality
Standards Handbook). Cf. Burlington N. & Santa Fe Ry. Co. v. White, 548 U.S. 53, 65–66 (2006) (considering
potentially contradictory statements of EEOC).
470 See, e.g., FDA v. Brown & Williamson Tobacco Corp., 529 U.S. 120, 144–46 (2000). Cf., e.g., Zuni Pub. Sch. Dist.
No. 89 v. Dep’t of Educ., 550 U.S. 81, 90–91 (2007) (noting Congress adopted language originally drafted by the
Secretary of Education without amendment or comment, and viewing this as evidence Congress did not intend to
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This use of an agency’s interpretation of a statute is distinct from the special weight, called
Chevron deference, that a court will sometimes give to an agency interpretation.471 Chevron
deference generally applies when a court is reviewing an agency’s official interpretation of a
statute that the agency is charged with administering.472 In such a situation, if a statute is silent or
ambiguous with respect to the specific issue being litigated, then Chevron instructs a court to give
the agency’s construction controlling weight, so long as it is reasonable.473 Even outside the
context of Chevron deference, though, when a court is determining for itself the best reading of
the statute, it will still consider an agency’s interpretation.474 Courts may view the agency’s
interpretation as evidence that the statute can bear a particular meaning, similar to a dictionary
definition.475
Two legal scholars suggested that “popular” constructions of a statute, especially those embodied
in the actions of those entities implementing that law, should be entitled to some special
weight.476 According to them, evidence of how a law has been implemented does not show
merely “peoples’ understanding of the [disputed] term . . . in the abstract,” as a dictionary would,
but gives “evidence of the understanding upon which people had acted,” and sometimes the ways
in which people have acted against their own interests.477 In this sense, they contend that
interpreters should give special weight to “action by the primary addressees who were required by
the very nature of the arrangement to make the initial decisions under it.”478 This view accords
with one of the central justifications given for deferring to agency interpretations under Chevron:
courts should give special weight to agency constructions of statutes that they administer because
they have special expertise in that subject area, and because Congress itself has given the agency
a special role in interpreting the statute.479 Notwithstanding these considerations, however, judges
regularly reject agency interpretations if they are contrary to the text of the statute or other strong
evidence of the statute’s meaning.480

disturb the agency’s interpretation of the relevant language).
471 See Chevron U.S.A., Inc. v. Natural Res. Def. Council, 467 U.S. 837, 842–43 (1984). For more on Chevron
deference, see CRS Report R44954, Chevron Deference: A Primer, by Valerie C. Brannon and Jared P. Cole. As that
report discusses, in recent years, the “major questions doctrine” mentioned earlier in the report has become one
limitation on the applicability of Chevron deference.
472 See Chevron, 467 U.S. at 842–43.
473 See id. at 844.
474 See, e.g., S.D. Warren Co., 547 U.S. at 377–78 (considering agency’s interpretation as evidence of statutory term’s
meaning even though the particular “expressions of agency understanding do not command deference”).
475 E.g., id. at 378 (“[T]he administrative usage of ‘discharge’ in this way confirms our understanding of the everyday
sense of the term.”); HART & SACKS, supra note 17, at 1270 (“Such action, manifestly, is especially cogent evidence
that the words of the statute would bear the meaning which the action necessarily attributed to them.”).
476 See HART & SACKS, supra note 17, at 1270.
477 See id. at 1269.
478 See id. at 1270. See also, e.g., NLRB v. SW Gen., Inc., 137 S. Ct. 929, 953–54 (2017) (Sotomayor, J., dissenting)
(considering as evidence the practices of executive branch prior to and following the enactment of the disputed
statutory text). Cf. Bd. of Trs. of the Leland Stanford Junior Univ. v. Roche Molecular Sys., Inc., 563 U.S. 776, 793
(2011) (noting the “common practice” of “parties operating under the act”).
479 See Chevron U.S.A., Inc. v. Natural Res. Def. Council, 467 U.S. 837, 843–44, 865 (1984).
480 See, e.g., SW Gen., Inc., 137 S. Ct at 943 (majority opinion) (rejecting as insubstantial evidence of executive
branch’s “post-enactment practice” under statute); Freeman v. Quicken Loans, Inc., 566 U.S. 624, 629–30 (2012)
(noting that an agency had authority to interpret statute but rejecting its interpretation as “manifestly inconsistent with
the statute [that the agency] purported to construe”).
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Practical Consequences
Judges may also rely on their own understandings of how a statute should be implemented to
interpret the statute’s meaning. Even textualists, who generally protest the use of consequentialist
reasoning, do regularly invoke policy consequences to evaluate the validity of a proffered
interpretation.481 If a court believes that the practical consequences of a particular interpretation
would undermine the purposes of the statute, the court may reject that reading even if it is the one
that seems most consistent with the statutory text.482 Similarly, judges will refer to concerns of
administrability when interpreting statutes.483 Judges may also rely on policy considerations to
limit the reach of a statute, if one possible construction would seem to expand the government’s
authority beyond what the judge believes to be reasonable.484
In one prominent example, the Supreme Court concluded in King v. Burwell that “the context and
structure of the [Patient Protection and Affordable Care] Act compel us to depart from what
would otherwise be the most natural reading of the pertinent statutory phrase.”485 The disputed
statute provided that the availability of certain tax credits rested in part on whether a taxpayer had
“enrolled in an insurance plan through ‘an Exchange established by the State.’”486 At issue was
whether these tax credits were “available in States that have a Federal Exchange rather than a
State Exchange.”487 The Court acknowledged that based solely on this statutory text, “it might
seem that a Federal Exchange cannot fulfill [the] requirement” of being “established by the
State.”488 Based on the statutory context and the “broader structure of the Act,” however, the
Court concluded that a strict textualist approach to interpreting the statute was not the best
reading of the statute.489 The Court reviewed the reforms that the Act aimed to achieve and
considered how the exchanges would actually operate under this plain-text reading.490 The Court
expressed that a reading that would deny tax credits to most individuals “could well push a

481 See, e.g., Krishnakumar, Reconsidering Substantive Canons, supra note 199, at 886–87 (noting that Justices Scalia
and Thomas referenced practical consequences in a number of their opinions). See also, e.g., Van Buren v. United
States, 141 S. Ct. 1648, 1659–60 (2021) (Barrett, J.) (looking to the “design” of a statute and concluding a particular
reading was “ill fitted” to its operation); Artis v. District of Columbia, 138 S. Ct. 594, 612 (2018) (Gorsuch, J.,
dissenting) (pointing out “some examples of the absurdities that follow” from the majority’s reading).
482 See, e.g., King v. Burwell, 576 U.S. 473, 488 (2015). Courts sometimes describe this as seeking to avoid absurd
results. See, e.g., Clinton v. City of New York, 524 U.S. 417, 429 (1998) (“Acceptance of the Government’s new-found
reading of [the disputed statute] ‘would produce an absurd and unjust result which Congress could not have
intended.’”) (quoting Griffin v. Oceanic Contractors, Inc., 458 U.S. 564, 574 (1982)); see generally John F. Manning,
The Absurdity Doctrine, 116 HARV. L. REV. 2387, 2390 (2003) (“Despite the absurdity doctrine’s deep roots, recent
intellectual and judicial developments have undermined the doctrine’s strong intentionalist foundations.”).
483 See, e.g., Robers v. United States, 572 U.S. 639, 644 (2014).
484 See, e.g., Van Buren, 141 S. Ct. at 1661 (concluding that the “fallout” from reading a criminal law to encompass “a
breathtaking amount of commonplace . . . activity” supported a narrower textual interpretation); Rapanos v. United
States, 547 U.S. 715, 721–22 (2006) (plurality opinion) (discussing the consequences stemming from the agency’s
reading of the law). Cf. Whitman v. Am. Trucking Ass’ns, 531 U.S. 457, 468 (2001) (“Congress . . . does not alter the
fundamental details of a regulatory scheme in vague terms or ancillary provisions—it does not, one might say, hide
elephants in mouseholes.”).
485 King, 576 U.S. at 497.
486 Id. at 483 (quoting 26 U.S.C. § 36B(b)-(c)).
487 Id.
488 Id. at 487.
489 Id. at 492.
490 Id. at 492–93.
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State’s individual insurance market into a death spiral.”491 Ultimately, the Court decided that it
was “implausible that Congress meant the Act to operate in this manner.”492
Justice Scalia authored the dissent in King, arguing that it was “quite absurd” to read “Exchange
established by the State” to mean “Exchange established by the State or the Federal
Government.”493 Arguing that “[w]ords no longer have meaning if an Exchange that is not
established by a State is ‘established by the State,’”494 the dissent described the majority opinion
as “rewriting the law under the pretense of interpreting it.”495 The majority opinion itself
recognized that “[r]eliance on context and structure in statutory interpretation is a ‘subtle
business, calling for great wariness lest what professes to be mere rendering becomes creation
and attempted interpretation of legislation becomes legislation itself.’”496 In the dispute before it,
on the other hand, the Court argued such reliance was warranted “to avoid the type of calamitous
result that Congress plainly meant to avoid.”497 The Court concluded by asserting that it was
required to “respect the role of the Legislature, and take care not to undo what it has done.”498
While King’s discussion of an interpretation’s practical consequences was quite obvious,499 courts
may also consider the policy consequences of a particular interpretation in more subtle ways.
Courts frequently will discuss pragmatic concerns in the context of a discussion of another
interpretive tool.500 Many of the substantive canons, for instance, explicitly favor certain policy
outcomes, inviting judges to choose the reading that comports with that outcome.501
Conclusion
When Congress understands how courts interpret statutes, it can draft according to the prevailing
interpretive conventions.502 Because courts act as the arbiters of statutory meaning and
necessarily shape the way a statute is implemented, Congress may be able to eliminate at least
some misunderstandings by legislating with judges in mind.503 Understanding the theories and

491 Id. at 492.
492 Id. at 494.
493 Id. at 498 (Scalia, J., dissenting) (internal quotation marks omitted).
494 Id. at 500.
495 Id. at 516.
496 Id. at 497–98 (majority opinion) (quoting Palmer v. Massachusetts, 308 U.S. 79, 83 (1939)).
497 Id. at 498. See also id. (“Congress passed the Affordable Care Act to improve health insurance markets, not to
destroy them. If at all possible, we must interpret the Act in a way that is consistent with the former, and avoids the
latter.”).
498 Id.
499 See id.
500 See, e.g., Zeppos, supra note 466, at 1108 (arguing empirical studies likely “undercount the role such
consequentialist concerns play in the Court’s decisionmaking process” because “practical considerations are masked by
the invocation of more formal sources of authority”).
501 See supra notes 329 to 331 and accompanying text.
502 See, e.g., Manning, Inside Congress’s Mind, supra note 31, at 1932–33 (2015) (noting importance to textualists of
creating stable background rules against which Congress may legislate). See also, e.g., Project on Statutory
Construction Promotes Inter-Branch Communications
, U.S. COURTS (Sept. 10, 2015),
http://www.uscourts.gov/news/2015/09/10/project-statutory-construction-promotes-inter-branch-communications
(discussing project through which federal appellate courts send Congress “opinions that note possible technical
problems in statutes,” using them as “teaching tools” for legislative drafters).
503 See, e.g., KATZMANN, supra note 111, at 92–93.
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tools that govern judicial statutory interpretation may be especially beneficial as some scholars
turn their attention to actual legislative processes and legislative drafting practices. A continued
dialogue between the courts and Congress can help ensure that, in Justice Thomas’s phrase,
Congress successfully “says in a statute what it means and means in a statute what it says.”504


504 Conn. Nat’l Bank v. Germain, 503 U.S. 249, 254 (1992). This phrase has been repeated in a number of Supreme
Court opinions by a variety of Justices. See, e.g., Henson v. Santander Consumer USA Inc., 137 S. Ct. 1718, 1725
(2017) (Gorsuch, J.); Simmons v. Himmelreich, 578 U.S. 621, 627 (2016) (Sotomayor, J.).
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Appendix. Canons of Construction
This appendix draws from two different works to present an exemplary list of the canons of
construction.505 The two works take different approaches to compiling the canons, and sometimes
disagree on what counts as a legitimate canon of construction.506 In their book Reading Law: The
Interpretation of Legal Texts
, Justice Antonin Scalia and Bryan Garner507 took an
“unapologetically normative” approach to this task, collecting only those canons that they
deemed valid under their approach to textualism.508 By contrast, a casebook authored by law
professor William Eskridge and others took a more descriptive approach, compiling the canons
“invoked by” the Supreme Court from 1986 to 2014.509 This appendix does not intend to favor a
position in any ongoing debates about the validity of the canons, and where feasible, notes
disagreement among the authors in the footnotes.
Some editorial choices were made in the process of combining and reproducing the authors’ lists.
These edits include some generalization and consolidation of canons.510 The list also omits a
number of canons that are too specific511 or otherwise outside the scope512 of this report, which
aims to provide a general overview of how courts interpret statutes. The appendix likewise
excludes canons that seem to represent substantive legal principles rather than assumptions about
how to read statutes.513

505 ANTONIN SCALIA & BRYAN A. GARNER, READING LAW: THE INTERPRETATION OF LEGAL TEXTS (2012); WILLIAM N.
ESKRIDGE, JR., PHILLIP P. FRICKEY, ELIZABETH GARRETT, & JAMES J. BRUDNEY, CASES AND MATERIALS ON LEGISLATION
AND REGULATION: STATUTES AND THE CREATION OF PUBLIC POLICY (5th ed. 2014). While a more recent edition of this
latter source has been published since the report’s author first compiled this list, the appendix containing these canons
was unchanged. This report therefore continues to cite to the fifth edition.
506 Compare, e.g., SCALIA & GARNER, supra note 505, at 359 (describing as a “false notion” the idea that statutory
exemptions should be strictly construed), with William N. Eskridge, Jr. & Philip P. Frickey, Foreword: Law As
Equilibrium
, 108 HARV. L. REV. 26, 105 (1994) (describing as statute-based canon the “narrow interpretation of
statutory exemptions”).
507 Bryan Garner’s biography describes him as “noted speaker, writer, and consultant regarding legal writing and
drafting;” he is the current editor-in-chief of Black’s Law Dictionary. Bryan Garner, SMU Dedman School of Law,
https://www.smu.edu/Law/Faculty/Profiles/Garner-Bryan-A (last visited Mar. 10, 2023).
508 SCALIA & GARNER, supra note 505, at 9.
509 ESKRIDGE ET AL., supra note 505, at 1195. This list is built upon a preliminary compilation created by Eskridge and
Frickey in 1994. See Eskridge & Frickey supra note 506, at 97. Professor Eskridge has acknowledged that this list does
not include “all possible canons.” William N. Eskridge, Jr., The New Textualism and Normative Canons, 113 COLUM.
L. REV. 531, 536 n.31 (2013) (reviewing SCALIA & GARNER, supra note 505).
510 For example, the Eskridge & Frickey list contained a number of different canons relating to federal preemption of
state law, which this list provides for with the general presumption against such preemption. See ESKRIDGE ET AL.,
supra note 505, at 1205–07; infra note 586 and accompanying text.
511 See, e.g., ESKRIDGE ET AL., supra note 505, at 1212–15 (discussing canons applicable to statutes governing a wide
variety of specific issue areas). For example, this appendix excludes a canon of patent law that creates a presumption
that “abstract ideas and laws of nature are not patentable.” Id. at 1214.
512 See, e.g., id. at 1199–1200 (discussing “canons” that apply when courts review agency interpretations of statutes).
See also
SCALIA & GARNER, supra note 505, at 53 (outlining the “interpretation principle” that “[e]very application of a
text to particular circumstances entails interpretation”).
513 For example, the Eskridge casebook describes a “[S]uper-strong rule against congressional interference with
President’s inherent powers, his executive authority.” ESKRIDGE ET AL., supra note 505, at 1204. Arguably, the cases
cited in support of this rule do establish such a principle, but do not describe this rule as a presumption about how to
generally read statutes. See, e.g., Dep’t of the Navy v. Egan, 484 U.S. 518, 530 (1988). Cf. Morrison v. Olson, 487 U.S.
654, 682 (1988) (invoking canon of constitutional avoidance to narrowly construe statute to avoid infringing
President’s removal powers).
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This appendix names and briefly describes each canon, citing either or both of the two lists and
applicable cases as appropriate. In many cases, the canon includes both the general rule and any
relevant exceptions, in accord with the modern understanding that the application of a canon is
highly context-dependent.514 The list distinguishes semantic canons from substantive canons, but
does not further group the canons.515 The canons are listed in alphabetical order.
Semantic Canons
1. “Artificial-Person Canon”:516 “The word person includes corporations and other
entities, but not the sovereign.”517
2. Casus Omissus: A matter not covered by a statute should be treated as
intentionally omitted (casus omissus pro omisso habendus est).518
3. “Conjunctive/Disjunctive Canon”:519 “And” usually “joins a conjunctive list,”
combining items, while “or” usually joins “a disjunctive list,” denoting
alternatives.520
4. Ejusdem Generis: A general term that follows an enumerated list of more specific
terms should be interpreted to cover only “matters similar to those specified.”521
5. Expresio Unius: “The expression of one thing implies the exclusion of others
(expressio unius est exclusio alterius).”522 This canon is strongest “when the
items expressed are members of an ‘associated group or series,’ justifying the

514 See discussion supra, “Justifications: Disrepute, Rehabilitation, and Empirical Studies.” See also SCALIA & GARNER,
supra note 505, at 59 (outlining the “principle of interrelating canons,” stating that “[n]o canon of interpretation is
absolute”).
515 Both lists from which this appendix is drawn do draw further distinctions, but such groupings require more
discussion and justification than would arguably be helpful here.
516 SCALIA & GARNER, supra note 505, at 273 (emphasis added).
517 Id. See also ESKRIDGE ET AL., supra note 505, at 1196 (noting Dictionary Act, 1 U.S.C. § 1, supplies default
statutory definitions). See, e.g., Burwell v. Hobby Lobby Stores, Inc., 573 U.S. 682, 707–08 (2014) (adopting
Dictionary Act’s definition of “person” to conclude corporations were covered by disputed statute); Vt. Agency of Nat.
Res. v. United States ex rel. Stevens, 529 U.S. 765, 780 (2000) (applying the “longstanding interpretive presumption
that ‘person’ does not include the sovereign”).
518 SCALIA & GARNER, supra note 505, at 93; State v. I.C.S., 145 So. 3d 350, 355 (La. 2014) (“We recognize the canon
casus omissus pro omisso habendus est, which means that a case omitted is to be held as intentionally omitted.”). See
also, e.g.
, Ebert v. Poston, 266 U.S. 548, 554 (1925) (“A casus omissus does not justify judicial legislation. This Act is
so carefully drawn as to leave little room for conjecture.” (citation omitted)). Cf. ESKRIDGE ET AL., supra note 505, at
1198 (“Avoid the implication of broad congressional delegation of agency authority when statute carefully limits
agency authority in particular matters.”).
519 SCALIA & GARNER, supra note 505, at 116 (emphasis added).
520 Id. See also ESKRIDGE ET AL., supra note 505, at 1197. See, e.g., City of Rome v. United States, 446 U.S. 156, 172
(1980) (“By describing the elements of discriminatory purpose and effect in the conjunctive [by using “and”], Congress
plainly intended that a voting practice not be precleared unless both discriminatory purpose and effect are absent.”);
United States v. Woods, 571 U.S. 31, 45 (2013) (“[T]he operative terms are connected by the conjunction ‘or.’ . . .
[That term’s] ordinary use is almost always disjunctive, that is, the words it connects are to ‘be given separate
meanings.’” (quoting Reiter v. Sonotone Corp., 442 U.S. 330, 339 (1979))). But cf. SCALIA & GARNER, supra note 505,
at 116–25 (discussing nuances introduced by the use of “negatives, plurals, and various specific wordings”).
521 Gooch v. United States, 297 U.S. 124, 128 (1936). Accord Hall St. Assocs., L.L.C. v. Mattel, Inc., 552 U.S. 576,
586 (2008) (“Under that rule [of ejusdem generis], when a statute sets out a series of specific items ending with a
general term, that general term is confined to covering subjects comparable to the specifics it follows.”). See also
SCALIA & GARNER, supra note 505, at 199; ESKRIDGE ET AL., supra note 505, at 1195.
522 SCALIA & GARNER, supra note 505, at 107. See also ESKRIDGE ET AL., supra note 505, at 1195. See, e.g., Lindh v.
Murphy, 521 U.S. 320, 330 (1997) (describing “negative implications raised by disparate provisions”).
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inference that items not mentioned were excluded by deliberate choice, not
inadvertence.”523
6. “Gender/Number Canon”:524 Usually, “the masculine includes the feminine (and
vice versa) and the singular includes the plural (and vice versa).”525
7. “General/Specific Canon”:526 Where two laws conflict, “the specific governs the
general (generalia specialibus non derogant).”527 That is, “a precisely drawn,
detailed statute pre-empts more general remedies,”528 and conversely, “a statute
dealing with a narrow, precise, and specific subject is not submerged by a later
enacted statute covering a more generalized spectrum.”529
8. “General-Terms Canon”:530 “General terms are to be given their general meaning
(generalia verba sunt generaliter intelligenda).”531
9. Grammar Canon: Statutes “follow accepted standards of grammar.”532
10. “Harmonious-Reading Canon”:533 “The provisions of a text should be
interpreted in a way that renders them compatible, not contradictory.”534

523 Barnhart v. Peabody Coal Co., 537 U.S. 149, 168 (2003) (quoting United States v. Vonn, 535 U.S. 55, 65 (2002)).
524 SCALIA & GARNER, supra note 505, at 129 (emphasis added).
525 Id. See also ESKRIDGE ET AL., supra note 505, at 1196 (noting Dictionary Act, 1 U.S.C. § 1, supplies default
statutory definitions). See, e.g., United States v. Hayes, 555 U.S. 415, 432 (2009) (Roberts, C.J., dissenting) (arguing
singular statutory term should be read to encompass the plural, by reference to the Dictionary Act and semantic
context); but see, e.g., Niz-Chavez v. Garland, 141 S. Ct. 1474, 1480 (2021) (emphasizing the use of “the singular
article ‘a’” to conclude that the statute referred to a singular term).
526 SCALIA & GARNER, supra note 505, at 183 (emphasis added).
527 Nitro-Lift Techs., L.L.C. v. Howard, 568 U.S. 17, 21 (2012). See also ESKRIDGE ET AL., supra note 505, at 1199
(“Specific provisions targeting a particular issue apply instead of provisions more generally covering the issue.”);
SCALIA & GARNER, supra note 505, at 183 (“If there is a conflict between a general provision and a specific provision,
the specific provision prevails (generalia specialibus non derogant).”).
528 Brown v. Gen. Servs. Admin., 425 U.S. 820, 834 (1976). See also ESKRIDGE ET AL., supra note 505, at 1210.
529 Radzanower v. Touche Ross & Co., 426 U.S. 148, 153 (1976). But as the authors point out in Reading Law, it can
be “difficult to determine whether a provision is a general or a specific one.” SCALIA & GARNER, supra note 505, at
187–88 (discussing Radzanower).
530 SCALIA & GARNER, supra note 505, at 101 (emphasis added).
531 Id. See, e.g., Dep’t of Hous. & Urban Dev. v. Rucker, 535 U.S. 125, 131 (2002) (giving unqualified statutory term
broad meaning). See also Arizona v. Tohono O’odham Nation, 818 F.3d 549, 557 (9th Cir. 2016) (“[A] word or phrase
is not ambiguous just because it has a broad general meaning under the generalia verba sunt generaliter intelligenda
canon of statutory construction.”).
532 ESKRIDGE ET AL., supra note 505, at 1197. See also SCALIA & GARNER, supra note 505, at 140. See, e.g., Niz-Chavez
v. Garland, 141 S. Ct. 1474, 1481 (2021) (discussing the use of definite versus indefinite articles); Carr v. United
States, 560 U.S. 438, 448 (2010) (“Consistent with normal usage, we have frequently looked to Congress’ choice of
verb tense to ascertain a statute’s temporal reach.”). Cf. Nielsen v. Preap, 139 S. Ct. 954, 964–65 (2019) (noting that
“an adverb cannot modify a noun,” but saying this rule of grammar is not dispositive and “merely complements” a
reading based on statutory context).
533 SCALIA & GARNER, supra note 505, at 180 (emphasis added).
534 Id. See also ESKRIDGE ET AL., supra note 505, at 1198 (“Avoid interpreting a provision in a way that is inconsistent
with the overall structure of the statute or with another provision or with a subsequent amendment to the statute or with
another statute enacted by a Congress relying on a particular interpretation.” (citations omitted)). See, e.g., Lindh v.
Murphy, 521 U.S. 320, 336 (1997) (favoring reading that “accords more coherence” to the disputed statutory
provisions).
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11. “Irreconcilability Canon”:535 “If a text contains truly irreconcilable provisions at
the same level of generality, and they have been simultaneously adopted, neither
provision should be given effect.”536
12. Legislative History Canons:537 “[C]lear evidence of congressional intent”
gathered from legislative history “may illuminate ambiguous text.”538 The most
“authoritative source for finding the Legislature’s intent lies in the Committee
Reports on the bill.”539 Floor statements, especially those made by a bill’s
sponsors prior to its passage, may be relevant,540 but should be used cautiously.541
“[T]he views of a subsequent Congress form a hazardous basis for inferring the
intent of an earlier one.”542
13. “Mandatory/Permissive Canon”:543 “Shall” is usually mandatory and imposes a
duty; “may” usually grants discretion.544
14. “Nearest-Reasonable-Referent Canon”:545 “When the syntax involves
something other than a parallel series of nouns or verbs, a prepositive or
postpositive modifier normally applies only to the nearest reasonable referent.”546
15. Noscitur a Sociis: “Associated words bear on one another’s meaning . . . .”547

535 SCALIA & GARNER, supra note 505, at 189 (emphasis added).
536 Id.
537 The authors of Reading Law disagree with the use of legislative history to discover statutory purpose and describe
the idea “that committee reports and floor speeches are worthwhile aids in statutory construction” as a “false notion.”
SCALIA & GARNER, supra note 505, at 367.
538 Milner v. Dep’t of the Navy, 562 U.S. 562, 572 (2011). See also ESKRIDGE ET AL., supra note 505, at 1202
(“Consider legislative history (the internal evolution of a statute before enactment) if the statute is ambiguous.”).
539 Garcia v. United States, 469 U.S. 70, 76 (1984). See also ESKRIDGE ET AL., supra note 505, at 1202 (“Committee
reports (especially conference committee reports reflecting the understanding of both House and Senate) are the most
authoritative legislative history, but cannot trump a textual plain meaning, and should not be relied on if they are
themselves ambiguous or imprecise.” (citations omitted)); id. at 1203 (“Committee report language that cannot be tied
to a specific statutory provision cannot be credited. House and Senate reports inconsistent with one another should be
discounted.” (citations omitted)).
540 See, e.g., Hamdan v. Rumsfeld, 548 U.S. 557, 580 n.10 (2006). See also ESKRIDGE ET AL., supra note 505, at 1203.
541 See, e.g., Garcia, 469 U.S. at 76 (“We have eschewed reliance on the passing comments of one Member, and casual
statements from the floor debates.” (citation omitted)). See also ESKRIDGE ET AL., supra note 505, at 1203. Cf. Gen.
Dynamics Land Sys., Inc. v. Cline, 540 U.S. 581, 599 (2004) (“Even from a sponsor, a single outlying statement cannot
stand against a tide of context and history, not to mention 30 years of judicial interpretation producing no apparent
legislative qualms.”).
542 Consumer Prod. Safety Comm’n v. GTE Sylvania, Inc., 447 U.S. 102, 117 (1980) (quoting United States v. Price,
361 U.S. 304, 313 (1960)). See also ESKRIDGE ET AL., supra note 505, at 1203.
543 SCALIA & GARNER, supra note 505, at 112 (emphasis added).
544 Id.; ESKRIDGE ET AL., supra note 505, at 1197. See, e.g., Kingdomware Techs., Inc. v. United States, 579 U.S. 162,
171 (2016) (“Unlike the word ‘may,’ which implies discretion, the word ‘shall’ usually connotes a requirement.”). But
see, e.g.
, SCALIA & GARNER, supra note 505, at 113–14 (noting controversy over whether “shall” is mandatory). Scalia
and Garner describe the first half of this canon as “mandatory words impose a duty,” without specifically naming
“shall” in the rule itself. SCALIA & GARNER, supra note 505, at 112.
545 SCALIA & GARNER, supra note 505, at 152 (emphasis added).
546 Id. See, e.g., Ray v. McCullough Payne & Haan, L.L.C., 838 F.3d 1107, 1111 (11th Cir. 2016).
547 SCALIA & GARNER, supra note 505, at 195. See also ESKRIDGE ET AL., supra note 505, at 1195. See, e.g., United
States v. Williams, 553 U.S. 285, 294 (2008) (“[T]he commonsense canon of noscitur a sociis . . . counsels that a word
is given more precise content by the neighboring words with which it is associated.”); Beecham v. United States, 511
U.S. 368, 371 (1994) (“That several items in a list share an attribute counsels in favor of interpreting the other items as
possessing that attribute as well.”). Cf. S.D. Warren Co. v. Me. Bd. of Envtl. Prot., 547 U.S. 370, 379–80 (2006)
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16. Ordinary Meaning Canon: Words should be given “their ordinary, everyday
meanings,”548 unless “Congress has provided a specific definition”549 or “the
context indicates that they bear a technical sense.”550
17. Plain Meaning Rule and Absurdity Doctrine: “Follow the plain meaning of the
statutory text, except when a textual plain meaning requires an absurd result or
suggests a scrivener’s error.”551
18. “Predicate-Act Canon”:552 “The law has long recognized that the
‘[a]uthorization of an act also authorizes a necessary predicate act.’”553
19. “Prefatory-Materials”554 andTitles-and-Headings”555 Canons: Preambles,
purpose clauses, recitals, titles, and headings are all “permissible indicators of
meaning,”556 though they generally will not be dispositive.557

(“[N]oscitur a sociis is no help absent some sort of gathering with a common feature to extrapolate.”).
548 SCALIA & GARNER, supra note 505, at 69. See also ESKRIDGE ET AL., supra note 505, at 1196. See, e.g., Perrin. v.
United States, 444 U.S. 37, 42 (1979) (“A fundamental canon of statutory construction is that, unless otherwise
defined, words will be interpreted as taking their ordinary, contemporary, common meaning.”). See also SCALIA &
GARNER, supra note 505, at 78 (“Words must be given the meaning they had when the text was adopted”); Perrin, 444
U.S. at 42 (“[W]e look to the ordinary meaning of the term . . . at the time Congress enacted the statute . . . .”).
549 ESKRIDGE ET AL., supra note 505, at 1196. See also SCALIA & GARNER, supra note 505, at 225. See, e.g., Nat’l Steel
Car, Ltd. v. Canadian Pac. Ry., Ltd., 357 F.3d 1319, 1328 (Fed. Cir. 2004) (noting that although “in some instances
there may be ambiguity” regarding whether the statute covered a single rail container, there was no ambiguity in that
case, given that “Congress has defined ‘vehicle’ with sufficient breadth to include an individual rail car”).
550 SCALIA & GARNER, supra note 505, at 69. See also ESKRIDGE ET AL., supra note 505, at 1196. See, e.g., Gustafson v.
Alloyd Co., 513 U.S. 561, 576 (1995) (holding statutory word “is a term of art”); cf., e.g., Rimini St., Inc. v. Oracle
USA, Inc., 139 S. Ct. 873, 879–80 (2019) (rejecting argument that statutory phrase is term of art).
551 ESKRIDGE ET AL., supra note 505, at 1195 (citations omitted). See also SCALIA & GARNER, supra note 505, at 56
(“supremacy-of-text principle”); id. at 234 (absurdity doctrine). See, e.g., Conn. Nat’l Bank v. Germain, 503 U.S. 249,
253–54 (1992) (“[C]ourts must presume that a legislature says in a statute what it means and means in a statute what it
says there.”); Public Citizen v. U.S. Dep’t of Justice, 491 U.S. 440, 454 (1989) (“Where the literal reading of a
statutory term would ‘compel an odd result,’ we must search for other evidence of congressional intent to lend the term
its proper scope.” (quoting Green v. Bock Laundry Machine Co., 490 U.S. 504, 509 (1989))); U.S. Nat’l Bank of Or. v.
Indep. Ins. Agents of Am., Inc., 508 U.S. 439, 462 (1993) (“[W]e are convinced that the placement of the quotation
marks in the 1916 Act was a simple scrivener’s error, a mistake made by someone unfamiliar with the law’s object and
design. . . . The true meaning of the 1916 Act is clear beyond question, and so we repunctuate.”); cf., e.g., Exxon Mobil
Corp. v. Allapattah Servs., 545 U.S. 546, 565 (2005) (noting that a result may be “odd” but not “absurd”).
552 SCALIA & GARNER, supra note 505, at 192 (emphasis added).
553 Luis v. United States, 578 U.S. 5, 26 (2016) (Thomas, J., concurring) (alteration in original) (quoting SCALIA &
GARNER, supra note 505, at 192). See also, e.g., State ex rel. Brown v. Klein, 22 S.W. 693, 695 (Mo. 1893)
(“[W]henever a power is given by a statute, everything necessary to the making of it effectual or requisite to attain the
end is implied. Quando lex aliquid concedit concedere videtur et id, per quod devenitur ad illud.”).
554 SCALIA & GARNER, supra note 505, at 217 (emphasis added).
555 Id. at 221 (emphasis added).
556 Id. at 217, 221. See also ESKRIDGE ET AL., supra note 505, at 1197. See, e.g., S.D. Warren Co. v. Me. Bd. Of Envtl.
Prot., 547 U.S. 370, 385 (2006) (relying on congressional declarations of policy); Almendarez-Torres v. United States,
523 U.S. 224, 234 (1998) (“‘[T]he title of a statute and the heading of a section’ are ‘tools available for the resolution
of a doubt’ about the meaning of a statute.” (quoting Bhd. of R.R. Trainmen v. Baltimore & Ohio R.R. Co., 331 U.S.
519, 529 (1947))).
557 See, e.g., Yates v. United States, 574 U.S. 528, 552 (2015) (Alito, J., concurring) (“Titles, of course, are . . . not
dispositive.”); Bhd. of R.R. Trainmen, 331 U.S. at 528 (“[H]eadings and titles are not meant to take the place of the
detailed provisions of the text.”).
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20. Presumption of Consistent Usage: “Generally, identical words used in different
parts of the same statute are . . . presumed to have the same meaning.”558
Conversely, “a material variation in terms suggests a variation in meaning.”559
21. “Presumption of Nonexclusive ‘Include’”:560 “[T]he term ‘including’ is not one
of all-embracing definition, but connotes simply an illustrative application of the
general principle.”561
22. “Presumption of Validity”:562 “An interpretation that validates outweighs one
that invalidates (ut res magis valeat quam pereat).”563 Stated another way, courts
should construe statutes to have effect.564
23. “Proviso Canon”:565 “A proviso,” or “a clause that introduces a condition,”
traditionally by using the word “provided,” “conditions the principal matter that
it qualifies—almost always the matter immediately preceding.”566
24. Punctuation Canon: Statutes “follow accepted punctuation standards,”567 and
“[p]unctuation is a permissible indicator of meaning.”568
25. Purposive Construction: “[I]nterpret ambiguous statutes so as best to carry out
their statutory purposes.”569

558 Robers v. United States, 572 U.S. 639, 643 (2014) (quoting Merrill Lynch, Pierce, Fenner & Smith Inc. v. Dabit,
547 U.S. 71, 86 (2006)) (internal quotation marks omitted); see also, e.g., Cochise Consultancy, Inc. v. United States ex
rel.
Hunt, 139 S. Ct. 1507, 1512 (2019) (“In all but the most unusual situations, a single use of a statutory phrase must
have a fixed meaning.”). See also ESKRIDGE ET AL., supra note 505, at 1198 (“presumption of statutory consistency”);
SCALIA & GARNER, supra note 505, at 170 (“presumption of consistent usage”).
559 SCALIA & GARNER, supra note 505, at 170. See also ESKRIDGE ET AL., supra note 505, at 1198 (“presumption of
meaningful variation”). See, e.g., Russello v. United States, 464 U.S. 16, 23 (1983) (“[Where] Congress includes
particular language in one section of a statute but omits it in another section of the same Act, it is generally presumed
that Congress acts intentionally and purposely in the disparate inclusion or exclusion.” (alteration in original) (quoting
United States v. Wong Kim Bo, 472 F.2d 720, 722 (5th Cir. 1972)) (internal quotation marks omitted)).
560 SCALIA & GARNER, supra note 505, at 132 (emphasis added).
561 Fed. Land Bank v. Bismarck Lumber Co., 314 U.S. 95, 100 (1941). See also SCALIA & GARNER, supra note 505, at
132 (“The verb to include introduces examples, not an exclusive list.”).
562 SCALIA & GARNER, supra note 505, at 66 (emphasis added).
563 Id. at 66. See, e.g., Ft. Leavenworth R. Co. v. Lowe, 114 U.S. 525, 534 (1885) (discussing approvingly United States
v. Cornell, 25 F. Cas. 646, 649 (D.R.I. 1819) (No. 14,867)). This principle overlaps with the canon of constitutional
avoidance. See infra note 583 and accompanying text; see, e.g., Virginia v. Black, 538 U.S. 343, 378 (2003) (Scalia, J.,
dissenting) (“[A]pplying the maxim ‘ut res magis valeat quam pereat’ we would do precisely the opposite of what the
plurality does here—that is, we would adopt the alternative reading that renders the statute constitutional rather than
unconstitutional.”) (emphasis omitted).
564 See Clark v. Barnard, 108 U.S. 436, 461 (1883) (“It is admitted, that if it does not mean this, it does not mean
anything, and we have already said that we are not at liberty to adopt that alternative. We must construe it, ut res magis
valeat quam pereat . . . .”). See also, e.g., Election Cases, 65 Pa. 20, 31 (1870) (concluding that the legislature could not
have intended to require something impossible, and therefore construing it not to require that).
565 SCALIA & GARNER, supra note 505, at 154 (emphasis added).
566 Id. See, e.g., Pennington v. United States, 48 Ct. Cl. 408, 411, 413 (1913) (rejecting argument that proviso was “a
separate and independent statute” and holding instead that, according to the general rule, it modified only “the enacting
clause to which [it was] attached”).
567 ESKRIDGE ET AL., supra note 505, at 1196. See, e.g., U.S. Nat’l Bank of Or. v. Indep. Ins. Agents of Am., 508 U.S.
439, 454 (1993) (“[T]he meaning of a statute will typically heed the commands of its punctuation.”).
568 SCALIA & GARNER, supra note 505, at 161. See, e.g., Jama v. ICE, 543 U.S. 335, 344 (2005) (“Each clause is
distinct and ends with a period, strongly suggesting that each may be understood completely . . . .”).
569 ESKRIDGE ET AL., supra note 505, at 1210. The casebook also describes a number of subject-area-specific
descriptions of purpose as canons; those are excluded from this appendix. See, e.g., id. at 1212 (“Sherman Act should
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26. Reddendo Singula Singulis: “[W]ords and provisions are referred to their
appropriate objects . . . .”570
27. Rule Against Surplusage: Courts should “give effect, if possible, to every clause
and word of a statute”571 so that “no clause is rendered ‘superfluous, void, or
insignificant.’”572
28. Rule of the Last Antecedent: “[A] limiting clause or phrase . . . should
ordinarily be read as modifying only the noun or phrase that it immediately
follows . . . .”573
29. “Scope-of-Subparts Canon”:574 “Material within an indented subpart relates
only to that subpart; material contained in unindented text relates to all the
following or preceding indented subparts.”575
30. Series-Qualifier Canon: “‘When there is a straightforward, parallel construction
that involves all nouns or verbs in a series,’ a modifier at the end of the list
‘normally applies to the entire series.’”576
31. “Subordinating/Superordinating Canon”:577 “Subordinating language (signaled
by subject to) or superordinating language (signaled by notwithstanding or
despite) merely shows which provision prevails in the event of a clash—but does
not necessarily denote a clash of provisions.”578

be applied in light of its overall purpose of benefitting consumers.”). Cf. SCALIA & GARNER, supra note 505, at 63 (“A
textually permissible interpretation that furthers rather than obstructs the document’s purpose should be favored.”); see,
e.g.
, Philadelphia v. Ridge Ave. Passenger R.R. Co., 102 Pa. 190, 196 (1883) (“[T]his purpose and object of the statute,
[under the proposed construction,] would be defeated; the absurdity of such a construction is therefore apparent.”).
570 Sandberg v. McDonald, 248 U.S. 185, 204 (1918). See also SCALIA & GARNER, supra note 505, at 214 (“Distributive
phrasing applies each expression to its appropriate referent . . . .”).
571 Duncan v. Walker, 533 U.S. 167, 174 (2001) (quoting United States v. Menasche, 348 U.S. 528, 538–39 (1955))
(internal quotation marks omitted).
572 Young v. UPS, 575 U.S. 206, 226 (2015) (quoting TRW Inc. v. Andrews, 534 U.S. 19, 31 (2001)) (internal
quotation mark omitted). See also ESKRIDGE ET AL., supra note 505, at 1197 (“Presumption against redundancy: avoid
interpreting a provision in a way that would render other provisions of the statute superfluous or unnecessary.”);
SCALIA & GARNER, supra note 505, at 174 (“If possible, every word and every provision is to be given effect (verba
cum effectu sunt accipienda
). None should be ignored. None should needlessly be given an interpretation that causes it
to duplicate another provision or to have no consequence.”). But see, e.g., Rimini St., Inc. v. Oracle USA, Inc., 139 S.
Ct. 873, 881 (2019) (“Sometimes the better overall reading of the statute contains some redundancy.”).
573 Barnhart v. Thomas, 540 U.S. 20, 26 (2003). See also ESKRIDGE ET AL., supra note 505, at 1197; SCALIA & GARNER,
supra note 505, at 144 (defining rule as applicable to “a pronoun, relative pronoun, or demonstrative adjective” because
“strictly speaking, only pronouns have antecedents”).
574 SCALIA & GARNER, supra note 505, at 156 (emphasis added).
575 Id. See, e.g., Jama v. ICE, 543 U.S. 335, 344 (2005) (“Each clause is distinct and ends with a period, strongly
suggesting that each may be understood completely without reading any further.”).
576 Lockhart v. United States, 577 U.S. 347, 364 (2016) (Kagan, J., dissenting) (quoting SCALIA & GARNER, supra note
505, at 147) (internal quotation marks omitted). Scalia and Garner describe this canon as applicable to either
prepositive or postpositive modifiers. SCALIA & GARNER, supra note 505, at 147. See also, e.g., Porto Rico Ry., Light
& Power Co. v. Mor, 253 U.S. 345, 348 (1920) (“When several words are followed by a clause which is applicable as
much to the first and other words as to the last, the natural construction of the language demands that the clause be read
as applicable to all.”); but see, e.g., Yellen v. Confederated Tribes of the Chehalis Reservation, 141 S. Ct. 2434, 2448
(2021) (concluding the series-qualifier canon did not apply based on the statutory context).
577 SCALIA & GARNER, supra note 505, at 126 (emphasis added).
578 Id. (quoted in part in NLRB v. SW Gen., Inc., 137 S. Ct. 929, 939 (2017)). See, e.g., Cisneros v. Alpine Ridge Grp.,
508 U.S. 10, 18 (1993) (“[T]he use of such a ‘notwithstanding’ clause clearly signals the drafter’s intention that the
provisions of the ‘notwithstanding’ section override conflicting provisions of any other section.”); see also Merit
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32. “Unintelligibility Canon”:579 “[A] statute must be capable of construction and
interpretation; otherwise it will be inoperative and void.”580
33. “Whole-Text Canon”:581 Courts “do not . . . construe statutory phrases in
isolation; [they] read statutes as a whole.”582
Substantive Canons
1. Canon of Constitutional Avoidance: “[W]here an otherwise acceptable
construction of a statute would raise serious constitutional problems, the Court
will construe the statute to avoid such problems unless such construction is
plainly contrary to the intent of Congress.”583
2. “Dog that Didn’t Bark”584 Presumption: A “prior legal rule should be retained if
no one in legislative deliberations even mentioned the rule or discussed any
changes in the rule.”585
3. Federalism Canons: Courts will generally require a clear statement before finding
that a federal statute “alter[s] the federal-state balance.”586 Thus, for example,

Mgmt. Grp., LP v. FTI Consulting, Inc., 200 L. Ed. 2d 183, 194 (2018) (stating that a notwithstanding clause indicates
that a certain provision “operates as an exception” to other provisions). Courts have recognized that the breadth of a
“notwithstanding” clause may be influenced by context. See, e.g., SW Gen., 137 S. Ct. at 940; Or. Nat. Res. Council v.
Thomas, 92 F.3d 792, 796–97 (9th Cir. 1996).
579 SCALIA & GARNER, supra note 505, at 134 (emphasis added).
580 State v. Partlow, 91 N.C. 550, 553 (1884). See also SCALIA & GARNER, supra note 505, at 134 (“An unintelligible
text is inoperative.”).
581 SCALIA & GARNER, supra note 505, at 167 (emphasis added).
582 United States v. Morton, 467 U.S. 822, 828 (1984). See also ESKRIDGE ET AL., supra note 505, at 1197; SCALIA &
GARNER, supra note 505, at 167. See, e.g., K Mart Corp. v. Cartier, Inc., 486 U.S. 281, 291 (1988) (“In ascertaining the
plain meaning of the statute, the court must look to the particular statutory language at issue, as well as the language
and design of the statute as a whole.”); Pennington v. Coxe, 6 U.S. (2 Cranch) 33, 52–53 (1804) (“That a law is the best
expositor of itself, that every part of an act is to be taken into view, for the purpose of discovering the mind of the
legislature; and that the details of one part may contain regulations restricting the extent of general expressions used in
another part of the same act, are among those plain rules laid down by common sense for the exposition of statutes
which have been uniformly acknowledged.”).
583 Edward J. DeBartolo Corp. v. Fla. Gulf Coast Bldg. & Constr. Trades Council, 485 U.S. 568, 575 (1988); cf., e.g.,
Holder v. Humanitarian Law Project, 561 U.S. 1, 17 (2010) (declining to apply the canon). See also ESKRIDGE ET AL.,
supra note 505, at 1203–04; SCALIA & GARNER, supra note 505, at 247.
584 Church of Scientology v. IRS, 484 U.S. 9, 17–18 (1987) (“All in all, we think this is a case where common sense
suggests, by analogy to Sir Arthur Conan Doyle’s ‘dog that didn’t bark,’ that an amendment having the effect petitioner
ascribes to it would have been differently described by its sponsor, and not nearly as readily accepted by the floor
manager of the bill.”). See also Anita S. Krishnakumar, The Sherlock Holmes Canon, 84 GEO. WASH. L. REV. 1, 4
(2016) (examining these “‘failure to comment’ arguments” as “the Sherlock Holmes canon”).
585 ESKRIDGE ET AL., supra note 505, at 1203. See, e.g., Zuni Pub. Sch. Dist. No. 89 v. Dep’t of Educ., 550 U.S. 81, 91
(2007) (“No one at the time—no Member of Congress, no Department of Education official, no school district or
State—expressed the view that this statutory language . . . was intended to require, or did require, the Secretary to
change the Department’s system of calculation, a system that the Department and school districts across the Nation had
followed for nearly 20 years . . . .”). The authors of Reading Law reject this canon. SCALIA & GARNER, supra note 505,
at 387. See also Koons Buick Pontiac GMC, Inc. v. Nigh, 543 U.S. 50, 73–74 (2004) (Scalia, J., dissenting) (“I have
often criticized the Court’s use of legislative history because it lends itself to a kind of ventriloquism. . . . The Canon of
Canine Silence that the Court invokes today introduces a reverse—and at least equally dangerous—phenomenon, under
which courts may refuse to believe Congress’s own words unless they can see the lips of others moving in unison.”).
586 ESKRIDGE ET AL., supra note 505, at 1205. See also id. at 1205–06; SCALIA & GARNER, supra note 505, at 290. See,
e.g.
, Bond v. United States, 572 U.S. 844, 860 (2014).
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courts require Congress to speak with “unmistakeable clarity” in order to
“abrogate state sovereign immunity.”587
4. In Pari Materia: “[S]tatutes addressing the same subject matter generally should
be read ‘as if they were one law.’”588
5. “Mens Rea Canon”:589 Courts should “presume that a criminal statute derived
from the common law carries with it the requirement of a culpable mental state—
even if no such limitation appears in the text—unless it is clear that the
Legislature intended to impose strict liability.”590 In the context of civil liability,
“willfulness . . . cover[s] not only knowing violations of a standard, but reckless
ones as well.”591
6. Nondelegation Doctrine: Courts should presume that “Congress does not delegate
authority without sufficient guidelines.”592
7. “Penalty/Illegality Canon”:593 “[A] statute that penalizes an act makes it unlawful
. . . .”594
8. “Pending-Action Canon”:595 “When statutory law is altered during the pendency
of a lawsuit, the courts at every level must apply the new law unless doing so
would violate the presumption against retroactivity.”596

587 Blatchford v. Native Vill. of Noatak, 501 U.S. 775, 785 (1991). See also ESKRIDGE ET AL., supra note 505, at 1209;
SCALIA & GARNER, supra note 505, at 281.
588 Wachovia Bank, Nat’l Ass’n v. Schmidt, 546 U.S. 303, 316 (2006) (quoting Erlenbaugh v. United States, 409 U.S.
239, 243 (1972)). See also ESKRIDGE ET AL., supra note 505, at 1201 (“In pari materia rule: when similar statutory
provisions are found in comparable statutory schemes, interpreters should presumptively apply them the same way.”);
id. at 1210 (“In pari materia: similar statutes should be interpreted similarly, unless legislative history or purpose
suggests material differences.”); SCALIA & GARNER, supra note 505, at 252 (“Statutes in pari materia are to be
interpreted together, as though they were one law.”). Cf. Smith v. City of Jackson, 544 U.S. 228, 233 (2005) (“[W]hen
Congress uses the same language in two statutes having similar purposes, particularly when one is enacted shortly after
the other, it is appropriate to presume that Congress intended that text to have the same meaning in both statutes.”);
ESKRIDGE ET AL., supra note 505, at 1201 (“Presumption that Congress uses same term consistently in different
statutes.”); id. (“Borrowed statute rule: when Congress borrows a statute, it adopts by implication interpretations placed
on that statute, absent indication to the contrary.”).
589 SCALIA & GARNER, supra note 505, at 303 (emphasis added).
590 Bond, 572 U.S. at 857. See also ESKRIDGE ET AL., supra note 505, at 1207; SCALIA & GARNER, supra note 505, at
303. See also, e.g., United States v. U.S. Gypsum Co., 438 U.S. 422, 437–38 (1978).
591 Safeco Ins. Co. of Am. v. Burr, 551 U.S. 47, 57 (2007). See also ESKRIDGE ET AL., supra note 505, at 1207.
592 ESKRIDGE ET AL., supra note 505, at 1204. See Mistretta v United States, 488 U.S. 361, 373 n.7 (1989) (“In recent
years, our application of the nondelegation doctrine principally has been limited to the interpretation of statutory texts,
and, more particularly, to giving narrow constructions to statutory delegations that might otherwise be thought to be
unconstitutional.”).
593 SCALIA & GARNER, supra note 505, at 295 (emphasis added).
594 Nat’l Fed’n of Indep. Bus. v. Sebelius, 567 U.S. 519, 664 (2012) (Scalia, Kennedy, Thomas, and Alito, JJ.,
dissenting). See also SCALIA & GARNER, supra note 505, at 295.
595 SCALIA & GARNER, supra note 505, at 266 (emphasis added).
596 Id. Cf. Bradley v. Richmond Sch. Bd., 416 U.S. 696, 711 (1974) (“[A] court is to apply the law in effect at the time
it renders its decision, unless doing so would result in manifest injustice or there is statutory direction or legislative
history to the contrary.”); but see Kaiser Aluminum & Chem. Corp. v. Bonjorno, 494 U.S. 827, 837 (1990) (noting
“apparent tension” between the rule of Bradley, 416 U.S. at 711, and the presumption against retroactivity but declining
to resolve that tension); id. at 841 (Scalia, J., concurring) (arguing these principles are not merely in tension but are “in
irreconcilable contradiction”).
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9. Presumption Against Extraterritoriality: Courts should presume, “absent a clear
statement from Congress, that federal statutes do not apply outside the United
States.”597
10. “Presumption Against Hiding Elephants in Mouseholes”:598
“Congress . . . does not alter the fundamental details of a regulatory scheme in
vague terms or ancillary provisions—it does not, one might say, hide elephants in
mouseholes.”599
11. Presumption Against Implied Repeals: “[R]epeals by implication are not
favored.”600
12. Presumption Against Implied Right of Action: Courts should not imply a
private remedy “unless . . . congressional intent [to create a private remedy] can
be inferred from the language of the statute, the statutory structure, or some other
source.”601 Without such intent, “a cause of action does not exist.”602

597 Bond v. United States, 572 U.S. 844, 857 (2014) (citing Morrison v. Nat’l Austl. Bank Ltd., 561 U.S. 247, 255
(2010)). See also ESKRIDGE ET AL., supra note 505, at 1208 (“Rule against extraterritorial application of U.S. law.
Presumption that Congress legislates with domestic concerns in mind.” (citations omitted)); SCALIA & GARNER, supra
note 505, at 268 (“A statute presumptively has no extraterritorial application (statuta suo clauduntur territorio, nec
ultra territorium disponunt
).”). Cf. ESKRIDGE ET AL., supra note 505, at 1201 (‘Presumption that statutes be interpreted
consistent with international law and treaties.”); id. at 1204 (“Presumption that U.S. law conforms to U.S. international
obligations. Presumption that Congress takes account of the legitimate sovereign interests of other nations when it
writes American laws.” (citations omitted)); id. at 1208 (“American laws apply to foreign-flag ships in U.S. territory
and affecting Americans, but will not apply to the ‘internal affairs’ of a foreign-flag ship unless there is a clear statutory
statement to that effect.”).
598 ESKRIDGE ET AL., supra note 505, at 1201 (emphasis added).
599 Whitman v. Am. Trucking Ass’ns, 531 U.S. 457, 468 (2001). See also ESKRIDGE ET AL., supra note 505, at 1201.
Cf., e.g., Bostock v. Clayton Cty., 140 S. Ct. 1731, 1753 (2020) (declining to apply the canon where the statute was
“written in starkly broad terms” and could not be considered a “mousehole”). Cf. Becerra v. Empire Health Found., 142
S. Ct. 2354, 2365 (2022) (citing Whitman to argue that a parenthetical phrase was “incapable of bearing” an
“interpretive weight” that would have overridden other indicia of statutory meaning).
600 Morton v. Mancari, 417 U.S. 535, 549 (1974) (quoting Posadas v. Nat’l City Bank, 296 U.S. 497, 503 (1936))
(internal quotation mark omitted). See also ESKRIDGE ET AL., supra note 505, at 1201, 1210 (“Presumption against
repeals by implication. But where there is a clear repugnancy between a more recent statutory scheme and an earlier
one, partial repeal will be inferred.” (citations omitted)); SCALIA & GARNER, supra note 505, at 327 (“Repeals by
implication are disfavored . . . . But a provision that flatly contradicts an earlier-enacted provision repeals it.”); id. at
336 (“A statute is not repealed by nonuse or desuetude.”). Cf. Posadas, 296 U.S. at 503 (“There are two well-settled
categories of repeals by implication—(1) where provisions in the two acts are in irreconcilable conflict, the later act to
the extent of the conflict constitutes an implied repeal of the earlier one; and (2) if the later act covers the whole subject
of the earlier one and is clearly intended as a substitute, it will operate similarly as a repeal of the earlier act.”).
601 Nw. Airlines v. Transp. Workers Union, 451 U.S. 77, 94 (1981). See also ESKRIDGE ET AL., supra note 505, at 1204
(“Presumption against ‘implying’ causes of action into federal statutes.”); id. at 1210 (“Presumption against private
right of action unless statute expressly provides one . . . .”); SCALIA & GARNER, supra note 505, at 313 (“A statute’s
mere prohibition of a certain act does not imply creation of a private right of action for its violation. The creation of
such a right must be either express or clearly implied from the text of the statute.”). Cf. ESKRIDGE ET AL., supra note
505, at 1210 (“When Congress enacts a specific remedy when no remedy was clearly recognized previously, the new
remedy is regarded as exclusive.”). See also, e.g., Va. Bankshares, Inc. v. Sandberg, 501 U.S. 1083, 1102 (1991)
(“[A]ny private right of action for violating a federal statute must ultimately rest on congressional intent to provide a
private remedy. From this the corollary follows that the breadth of the right once recognized should not, as a general
matter, grow beyond the scope congressionally intended.” (citation omitted)).
602 Alexander v. Sandoval, 532 U.S. 275, 286 (2001).
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13. Presumption Against Retroactive Legislation: “[C]ourts read laws as
prospective in application unless Congress has unambiguously instructed
retroactivity.”603
14. Presumption Against Waiver of Sovereign Immunity: A waiver of sovereign
immunity “cannot be implied but must be unequivocally expressed.”604
15. Presumption for Retaining the Common Law: “‘[W]hen a statute covers an
issue previously governed by the common law,’ [courts] must presume that
‘Congress intended to retain the substance of the common law.’”605
16. Presumptions in Favor of Judicial Process: Courts sometimes require clear
statements from Congress in order to bar judicial review of certain claims.606
17. “Presumption of Continuity”:607 “Congress does not create discontinuities in
legal rights and obligations without some clear statement.”608
18. Presumption of Legislative Acquiescence: “[A] long adhered to administrative
interpretation dating from the legislative enactment, with no subsequent change
having been made in the statute involved, raises a presumption of legislative
acquiescence . . . .”609 This also applies to judicial interpretations of the statute.610

603 Vartelas v. Holder, 566 U.S. 257, 266 (2012). See also ESKRIDGE ET AL., supra note 505, at 1207; SCALIA &
GARNER, supra note 505, at 261. Cf. ESKRIDGE ET AL., supra note 505, at 1209 (“[L]aw takes effect on date of
enactment.” (citing Gozlon-Peretz v. United States, 498 U.S. 395, 404 (1991))).
604 United States v. King, 395 U.S. 1, 4 (1969). See also ESKRIDGE ET AL., supra note 505, at 1209; SCALIA & GARNER,
supra note 505, at 281. See also, e.g., FAA v. Cooper, 566 U.S. 284, 290 (2012). The same is true for a statute to waive
state sovereign immunity. See infra note 587. Cf. ESKRIDGE ET AL., supra note 505, at 1209 (“Presumption that federal
agencies launched into commercial world with power to ‘sue and be sued’ are not entitled to sovereign immunity.”).
605 Kirtsaeng v. John Wiley & Sons, Inc., 568 U.S. 519, 538 (2013) (first alteration in original) (quoting Samantar v.
Yousuf, 560 U.S. 305, 320 n.13 (2010)). See also ESKRIDGE ET AL., supra note 505, at 1208 (“Presumption in favor of
following common law usage and rules where Congress has employed words or concepts with well-settled common
law traditions.”); SCALIA & GARNER, supra note 505, at 318 (“A statute will be construed to alter the common law only
when that disposition is clear.”); id. at 320 (“A statute that uses a common-law term, without defining it, adopts its
common-law meaning.”). See also, e.g., Evans v. United States, 504 U.S. 255, 259 (1992) (“[A] statutory term is
generally presumed to have its common-law meaning.” (quoting Taylor v. United States, 495 U.S. 575, 592 (1990))
(internal quotation mark omitted)).
606 ESKRIDGE ET AL., supra note 505, at 1207 (“Presumption in favor of judicial review.”); id. (“Rule against
interpreting statutes to deny a right to jury trial.”); id. (“Super-strong rule against implied congressional abrogation or
repeal of habeas corpus.”); id. at 1208 (“Presumption against exhaustion of remedies requirement for lawsuit to enforce
constitutional rights.”); id. (“Presumption that judgments will not be binding upon persons not party to adjudication.”);
id. (“Presumption against foreclosure of private enforcement of important federal rights.”). See, e.g., Demore v. Hyung
Joon Kim, 538 U.S. 510, 517 (2003). But see SCALIA & GARNER, supra note 505, at 367 (describing as a “false notion”
the idea “that a statute cannot oust courts of jurisdiction unless it does so expressly”).
607 ESKRIDGE ET AL., supra note 505, at 1201 (emphasis added).
608 Id. See Finley v. United States, 490 U.S. 545, 554 (1989) (“Under established canons of statutory construction, ‘it
will not be inferred that Congress, in revising and consolidating the laws, intended to change their effect unless such
intention is clearly expressed.’” (quoting Anderson v. Pac. Coast S.S. Co., 225 U.S. 187, 199 (1912))); Green v. Bock
Laundry Mach. Co., 490 U.S. 504, 521 (1989) (“A party contending that legislative action changed settled law has the
burden of showing that the legislature intended such a change.”).
609 Baker v. Compton, 211 N.E.2d 162, 164 (Ind. 1965) (citing Costanzo v. Tillinghast, 287 U.S. 341, 345 (1932)). See
also
ESKRIDGE ET AL., supra note 505, at 1202 (“acquiescence rules”); id. at 1199 (“Even informal and unsettled agency
interpretations (such as those embodied in handbooks or litigation briefs) may be useful confirmations for the
interpreter’s interpretation of statutory language.”).
610 E.g., Shapiro v. United States, 335 U.S. 1, 16 (1948) (“In adopting the language used in the earlier act, Congress
‘must be considered to have adopted also the construction given by this Court to such language, and made it a part of
the enactment.’” (quoting Hecht v. Malley, 265 U.S. 144, 153 (1924))). See also SCALIA & GARNER, supra note 505, at
322 (“If a statute uses words or phrases that have already received authoritative construction by the jurisdiction’s court
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More broadly, “when a statute refers to a general subject, the statute adopts the
law on that subject as it exists whenever a question under the statute arises.”611 If
Congress reenacts a statute without any change, it incorporates any settled
judicial constructions of the statute “so broad and unquestioned that [a court]
must presume Congress knew of and endorsed it.”612 However, “[o]rdinarily,
. . . courts are slow to attribute significance to the failure of Congress to act on
particular legislation.”613
19. Presumption of Narrow Construction of Exceptions: “An exception to a
‘general statement of policy’ is ‘usually read . . . narrowly in order to preserve the
primary operation of the provision.’”614
20. “Presumption of Purposive Amendment”:615 Courts should assume that
Congress intends any statutory “amendment to have real and substantial
effect.”616
21. “Repeal-of-Repealer Canon”:617 “The repeal or expiration of a repealing statute
does not reinstate the original statute.”618
22. “Repealability Canon”:619 “[O]ne legislature is competent to repeal any act
which a former legislature was competent to pass; and . . . one legislature cannot
abridge the powers of a succeeding legislature.”620

of last resort, or even uniform construction by inferior courts or a responsible administrative agency, they are to be
understood according to that construction.”).
611 Jam v. Int’l Fin. Corp., 139 S. Ct. 759, 769 (2019) (describing this as the “‘reference’ canon”).
612 Jama v. ICE, 543 U.S. 335, 349 (2005) (holding there was no such “congressional ratification”). ESKRIDGE ET AL.,
supra note 505, at 1202 (“re-enactment rule”); see also, e.g., United States v. Davis, 139 S. Ct. 2319, 2331 (2019)
(referring to but rejecting application of the “reenactment canon”).
613 Bob Jones Univ. v. United States, 461 U.S. 574, 600 (1983).
614 Maracich v. Spears, 570 U.S. 48, 60 (2013) (quoting Commissioner v. Clark, 489 U.S. 726, 739 (1989) (alteration in
original)). See also ESKRIDGE ET AL., supra note 505, at 1199, 1211. See also, e.g., A.H. Phillips, Inc. v. Walling, 324
U.S. 490, 493 (1945) (“Any exemption from . . . remedial legislation must . . . be narrowly construed, giving due regard
to the plain meaning of statutory language and the intent of Congress.”). But see SCALIA & GARNER, supra note 505, at
359 (describing as “false notion” the idea “that tax exemptions—or any other exemptions for this matter—should be
strictly construed”); BP p.l.c. v. Mayor & City Council of Baltimore, 141 S. Ct. 1532, 1538–39 (2021) (rejecting
narrow construction of exception and saying the Court has “no right to place our thumbs on one side of the scale or the
other”). Cf., e.g., Bostock v. Clayton Cty., 140 S. Ct. 1731, 1747 (2020) (“Nor is there any such thing as a ‘canon of
donut holes,’ in which Congress’s failure to speak directly to a specific case that falls within a more general statutory
rule creates a tacit exception. Instead, when Congress chooses not to include any exceptions to a broad rule, courts
apply the broad rule.”); Andrus v. Glover Constr. Co., 446 U.S. 609, 616–17 (1980) (“Where Congress explicitly
enumerates certain exceptions to a general prohibition, additional exceptions are not to be implied . . . .”).
615 ESKRIDGE ET AL., supra note 505, at 1198 (emphasis added).
616 Stone v. INS, 514 U.S. 386, 397 (1995). See also ESKRIDGE ET AL., supra note 505, at 1198 (“[S]tatutory
amendments are meant to have real and substantial effect.”); id. at 1202 (“Statutory history (the formal evolution of a
statute, as Congress amends it over the years) is always potentially relevant.”); SCALIA & GARNER, supra note 505, at
256 (“If the legislature amends or reenacts a provision other than by way of a consolidating statute or restyling project,
a significant change in language is presumed to entail a change in meaning.”). See also, e.g., Rumsfeld v. Forum for
Acad. & Institutional Rights, Inc., 547 U.S. 47, 57–58 (2006) (“We refuse to interpret the Solomon Amendment in a
way that negates its recent revision, and indeed would render it a largely meaningless exercise.”).
617 SCALIA & GARNER, supra note 505, at 334 (emphasis added).
618 Id.
619 Id. at 278 (emphasis added).
620 Fletcher v. Peck, 10 U.S. (6 Cranch) 87, 135 (1810). See also SCALIA & GARNER, supra note 505, at 278 (“The
legislature cannot derogate from its own authority or the authority of its successors.”).
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23. Rule of Lenity: “Ambiguity in a statute defining a crime or imposing a penalty should be
resolved in the defendant’s favor.”621

Author Information

Valerie C. Brannon

Legislative Attorney



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621 SCALIA & GARNER, supra note 505, at 296. See also ESKRIDGE ET AL., supra note 505, at 1207, 1213. E.g., Liparota
v. United States, 471 U.S. 419, 427 (1985). Cf. ESKRIDGE ET AL., supra note 505, at 1207 (“Rule of lenity may apply to
civil sanction that is punitive or when underlying liability is criminal.”); see also SCALIA & GARNER, supra note 505, at
297–98 (discussing this “interpretive problem”).
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