Inside the Unsolved Murder of JFK's Mistress Who Some Say 'Had to Die Because She Knew Too Much'

She met John F. Kennedy at a prep school dance and in the early 1960s, began an affair with the president that lasted until the time of his assassination. One year later, on Oct. 12, 1964, Mary Pinchot Meyer was shot dead while taking an afternoon walk on a Georgetown towpath in Washington, D.C., at age 43.

Nearly fifty three years later, her murder remains unsolved. Was it a random act of violence or did someone want her dead?

“She was shot in the head,” says author Nina Burleigh, who wrote about artist and socialite Pinchot Meyer in the 1999 biography A Very Private Woman. “Passersby heard screams and a witness looked over the wall and saw a man standing near her body. The police came and shortly arrested a black male [Ray Crump Jr.] soaking wet who said he fell into the Potomac while fishing. … No gun was ever found.”

Crump Jr. pled not guilty and was acquitted at trial for lack of evidence in July 1965.

While he is still the only suspect, there have been theories that Pinchot Meyer’s death may have been linked to her affair with JFK. Says Burleigh: “The theory is that she had to die because she knew too much.”

”Her murder just ten days after the Warren Commission report was released makes a lot of people suspicious that she had to be silenced,” Burleigh notes, adding: “She lived in a world of secrets … the secrets of spies running complicated international plots, trying to control a dangerous world at the dawn of the nuclear age.”

Adding to the mystery, in the hours after Pinchot Meyer’s death, chief of CIA counterintelligence James Jesus Angleton broke into her artist studio (which was attached to her brother-in-law Ben Bradlee’s house) to find her diary.

“In Bradlee’s memoir, he revealed that he caught CIA counter intelligence master James Angleton breaking into Mary’s studio the night of the murder and looking for her diary,” explains Burleigh. “Bradlee found the diary looked at it.”

In his 1996 autobiography, A Good Life, Bradlee said Angleton confessed that his concern for the slain JFK’s reputation led him to search for Meyer’s diary of their affair with the intention of destroying it. When he later discovered that Angleton had preserved the diary, Bradlee said he took it back from the CIA counterintelligence chief. “Despite the braying of the knee jerks about some public right to know,” Bradlee said his wife, Pinchot Meyer’s sister Antoinette “Tony” Pinchot, burned the diary.

Pinchot Meyer, daughter of Amos Pinchot, a wealthy Progressive lawyer, and Ruth Pickering Pinchot, a writer and activist, “was a true American aristocrat, the beautiful daughter,” says Burleigh. “Mary was raised on Park Avenue … educated at the finest schools, a debutante, basically an American princess.”

“She met JFK at a prep school dance,” says Burleigh, the national politics correspondent for Newsweek. “They were teens. He supposedly cut in on her date.”

After graduating from Vassar, Pinchot Meyer went on to marry Cord Meyer, a high-ranking CIA official, in 1945.

While it’s not clear exactly when the affair with JFK began, Burleigh believes it was sometime in 1961 or 1962. “Her name first appears on the White House logs in October 1962,” she says. “She was by his side … She was often signed in when Jackie was away…”

Adds Burleigh: “White House counsel Myer Feldman told me, ‘Mary was almost a part of the furniture.’ ”

Prior to JFK becoming president, Pinchot Meyer and her husband had lived next door to Kennedy and his wife, future First Lady Jackie Kennedy, while he was still a senator. And her sister Tony later married Washington Post editor Ben Bradlee, one of JFK’s closest confidantes, further cementing their friendship.

In his autobiography, Bradlee claimed he knew nothing of JFK’s reported affairs — including with Pinchot Meyer — while the president was still alive. “Like everyone else, we had heard reports of presidential infidelity, but we were always able to say we knew of no evidence, none,” he wrote. But after reading Pinchot Meyer’s diary describing the affair, Bradlee said “it was clear that the lover had been the president of the United States, though his name was never mentioned.” He added that he “was truly appalled by the realization of the extent of the deceit involved.”

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Many say Pinchot Meyer, an artist and free thinker who experimented with pot and LSD, was different than JFK’s other mistresses — that they had an “intellectual kinship.”

“It’s hard to say,” says Burleigh. “My research led me to believe Kennedy was a sex addict … and like the ‘Mad Men’ of the TV show. She was very upper class, and ahead of her time in terms of modern art, personal style, using marijuana and LSD — very much a precursor to the culture we associate with the 1960s.”

In April 1962, Pinchot Meyer visited Timothy Leary, a former Harvard University psychology lecturer who later claimed in his 1983 autobiography, Flashbacks, that Pinchot Meyer asked him to teach her how to run an LSD session.

Leary said Pinchot Meyer told him, in what he later realized was a reference to JFK, “I have this friend who’s a very important man. He’s impressed by what I’ve told him about my own LSD experiences and what other people have told him. He wants to try it himself.”

Leary said Pinchot Meyer believed that if powerful men took LSD they would have revelations that would ultimately end world conflict.

“It’s known that she smoked pot,” says Burleigh. “I also interviewed Timothy Leary in California months before his death. He confirmed to me what he had written, that she came to his place in upstate New York and asked him to try it with her, then took some back to — Leary believed — turn on powerful men.”

Burleigh added, “I don’t think Leary was 100 percent a credible source on this but he said she knew JFK had to die because he was looking to make peace with the Russians, which the military industrial powers opposed.”

Pinchot Meyer filed for divorce from her husband in 1958, shortly after their 9-year-old son was killed in a car accident. Burleigh says “their marriage fell apart over the grief.” Pinchot Meyer, a pacifist, later became critical of the CIA’s covert activities.

Whether Jackie was aware of their affair is unknown. “Maybe, nobody knows,” says Burleigh. “She would sometimes seat them together. Either that meant she trusted her or she thought Mary was keeping Kennedy entertained in a good way.”

While the murder remains unsolved, Peter Janney, the son of one of the top CIA agents at the time, has written his own book, Mary’s Mosaic, claiming that his father was in on a CIA plot to murder Pinchot Meyer.

It’s a theory Burleigh rejects after coming to believe that Pinchot Meyer was most probably murdered by Ray Crump Jr., the man charged and later acquitted of her murder.

“The evidence against him was strong but circumstantial (no gun was ever found), but my investigation led me to believe Crump was entirely capable of violent behavior,” Burleigh wrote in a 2012 piece for the Daily Beast. “His long post-acquittal record included stints in federal prison for repeat arsons and the rape of a 13-year-old.”

Much like that of her presidential lover, the mystery surrounding Pinchot Meyer’s death lives on — as does her legacy.

“I was told in the last few years of her life, she told friends that she thought people were breaking into her house, rifling through her things,” says Burleigh. “I’m not sure she ever said she was afraid for her life. She was a bold and fearless sort of woman.”