In the fall of 1964, the New York Herald Tribune ran a story with the headline, "FBI Chief Calls Martin Luther King 'The Most Notorious Liar in Country.'" J. Edgar Hoover, then the director of the FBI, had found himself on the defense after King, perhaps the most prominent civil rights activist of the 1950s and 60s, accused the bureau of not enforcing civil rights law and using Jim Crow-era tactics to suppress blacks. Hoover's real reasoning for labeling King a "notorious liar," however, was based on information he and few others were privy to: the details of King's sex life.

Despite knowledge among King's inner circle, he had never been publicly known as a lothario—but Hoover planned to out him, with hopes of soiling his reputation and derailing the civil rights movement. The New York Times Magazine recently published an uncensored letter from the FBI to King. In it, the author threatens to release news of King's extramarital affairs, information which was ascertained through FBI wiretaps in King's home, office, and various hotel rooms.

The letter was written anonymously—it is later confirmed by the Senate to be the work of Hoover despite the intended authorial misdirection—and has long been proof of Hoover's malicious crusade against the celebrated activist. Portions detailing King's sex life were previously redacted—until earlier this summer, when Yale historian Beverly Gage found a copy "tucked away in a reprocessed set of [Hoover's] official and confidential files at the National Archives."

"Lend your sexually psychotic ear to the enclosure," the letter warns. "You will find yourself in all your dirt, filth, evil and moronic talk exposed on the record for all time."

But it didn't stop there. The final paragraph hints at an attempt to get King to commit suicide. "King, there is only one thing left for you to do. You know what it is... There is but one way out for you. You better take it..."

Ultimately, the FBI's threats proved weak, and King's legacy would remain intact. Gage writes in the Times:

Luckily, in 1964 the media were far more cautious. One oddity of Hoover's campaign against King is that it mostly flopped, and the F.B.I. never succeeded in seriously damaging King's public image. Half a century later, we look upon King as a model of moral courage and human dignity. Hoover, by contrast, has become almost universally reviled. In this context, perhaps the most surprising aspect of their story is not what the F.B.I. attempted, but what it failed to do.

Below, via the National Archives, the letter in its entirety.

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