Manner, Cause & Mechanisms of Death: 3 Key Differences

When a person passes away, it's the medical examiner's or coroner's job to determine the exact reason why they died. On the death certificate, they will list the person's manner, cause, and mechanism of death.

These details mean everything to a coroner, a forensic scientist, or someone else who conducts an autopsy for their job. It's how they ensure justice is served and peace is delivered to vulnerable families. 

Jump ahead to these sections:

• What is a Manner of Death?
• What is a Cause of Death?
• What is a Mechanism of Death?
• Manner of Death vs. Cause of Death
• Manner of Death vs. Mechanism of Death
• Mechanism of Death vs. Cause of Death

If you're interested in one of these careers or simply want to know more, then this article is for you. One of the first things you'll need to learn is the manner, cause, and mechanism of death and what each one means. Keep reading to learn how to distinguish each.

What is a Manner of Death?

When a coroner is determining the reason why someone died, they're going to look at the cause, mechanism, and manner of death. Together, all three give a detailed picture about what occurred. We'll discuss cause and mechanism below, and we'll take a look at the manner of death here. 

The five manners of death include natural deaths, accidental deaths, suicide, homicide, and undetermined.  The manner of death may also be marked as "pending" until further investigation is completed. Let's dig into this a bit deeper.

• Natural death: Natural death is the type of event when someone says their grandfather died of "old age." However, old age, strictly speaking, can't kill you. Since there is no one method of recording death due to organs slowly quitting and the body no longer functioning due to age, the manner of death is recorded as "natural death" or a "natural process. Natural deaths are also used to categorize deaths due to disease. For example, death from cancer is placed under the "natural death" category.
• Accidental death: This category includes all deaths that are truly accidental. Included in this category are falls, car accidents, and other incidents that cause death where no one individual was the instigator or willful cause. 
• Suicide: Suicide includes intentional or unintentional drug overdoses and any other method by which the deceased killed themselves.
• Homicides: Homicide includes all deaths whereby one party is responsible for another party's death. This includes first-degree murder and manslaughter.
• Undetermined: An undetermined death applies to deaths that are unexplainable. For example, sudden infant death syndrome (SIDS) falls into this category since there is no specific explanation for why the child passes away.

What is a Cause of Death?

The cause of death is the specific thing that led to a person's death. This can include the disease that caused life to cease or a specific condition like suffocation.

Medical examiners and coroners, in particular, deal with specifics. The specifics they find lead them to discover the truth behind a person's death. In some cases, these differences can be the matter of determining a natural death or homicide. Ruling out foul play is a critical part of a coroner's job.

The specific injury that led to a person's death, the cause, can sometimes be glaringly obvious. At other times, a detailed autopsy is necessary to find the truth. 

Here are some examples of causes of death:

• Heart failure
• Asthma
• Stroke
• Chronic obstructive pulmonary disease (COPD)
• Cancer
• Kidney disease

What is a Mechanism of Death?

The mechanism of death relies on important technicalities. A gunshot wound is a great example — but you could say that it’s obvious. Someone was shot so they die of a gunshot wound. There’s no other explanation, right?

The “mechanism of death” concept takes it a step further. A victim doesn’t truly die of a gunshot wound. He dies of excessive blood loss caused by the gunshot wound. The difference seems tiny, but it means a lot. That means the mechanism would be categorized as blood loss — and to use the technical term, he dies of exsanguination. 

Here are some examples of the mechanism of death:  

• Blood loss
• Lack of oxygen
• Cardiac arrhythmia
• Lack of blood flow to the brain
• Sepsis
• Respiratory depression and paralysis

Manner of Death vs. Cause of Death

Now that you know the basic definitions, let's break down how each category differs. The best way to look at these differences is to give practical examples.

The first thing to do is remember that the manner of death is the overarching, broad category of death. The manner is only one of five including natural, accidental, suicide, homicide, or undetermined. It's the "category" of death if you will.

The cause of death is the specific thing that led to the person's death. This can include things like heart failure, cancer, and kidney disease.

So, if you have a 65-year-old male who passed away due to kidney disease, the manner of death would be "natural death" and the cause would be kidney disease.

Manner of Death vs. Mechanism of Death

When determining the manner of death vs. the mechanism, again the best thing to do is go back to the definitions of each.

The manner of death can only be the five categories that a death is placed into including natural, accidental, suicide, homicide, or undetermined. 

The mechanism, however, refers to the exact, explicit reason that caused the death to occur. This includes things like lack of oxygen or blood loss.

So, if a 30-year-old female passed away after getting shot, the manner of death would be homicide but the mechanism of death would likely be blood loss.

Mechanism of Death vs. Cause of Death

Determining the mechanism of death vs. the cause of death can be more tricky since both are related to the reason why a person dies.

The easiest way to distinguish the two is to remember that the cause of death is the basic reason why they died, whereas the mechanism is the specific reason why the body ceased to exist.

Causes are things like diseases and wounds, whereas mechanisms include things like lack of oxygen or blood loss.

If, for example, a 53-year-old male died from an asthma attack, the cause of death would be asthma and the mechanism would be lack of oxygen.

In the case of a heart attack, the cause is a heart attack but the mechanism is cardiac arrhythmia or cardiogenic shock. 

Manner of Death, Cause of Death, Mechanism of Death: Summing Up

Whether you’re interested in moving toward a medical examiner’s career or just curious, understanding the difference between the manner of death, cause of death, and mechanism of death can play an important part in reading death certificates.

The next time you hear about a crime situation, try to determine the manner, cause, and mechanisms of death on your own. Just remember that the manner includes those five broad categories (natural, accidental, homicide, suicide, or undetermined), cause means the specific illness or injury that caused the death, and the mechanism is the exact reason the body ceased to live.

If you're looking for more information on what occurs after a person's death, check out our guides on how to get a death certificate, how to write an obituary, and how to plan a funeral.

Sources:

1. Center for Disease Control (CDC). “Medical Examiners’ and Coroners’ Handbook on Death Registration and Fetal Death Reporting.” 2003, www.cdc.gov/nchs/data/misc/hb_me.pdf