The FBI’s attempt to discredit Martin Luther King Jr – new details of which are only just emerging some 55 years later – was a mammoth operation involving undercover informants, wiretapped phones and bugged hotel rooms.
J Edgar Hoover, the bureau’s notorious director, believed the material gathered by his agents in the Sixties exposed the civil rights leader as a “notorious liar” and “one of the lowest characters in the country”.
It included a tape which, according to an FBI summary, recorded King laughing and offering “advice” as a fellow Baptist minister “forcibly raped” a woman just a few minutes walk from The White House in Washington DC.
But despite their attempts to spread the story of King’s “sex orgies” and 40-plus extramarital affairs, the story never appeared in the media.
“They tried, but the press would not touch it,” said David Garrow, a Pulitzer Prize-winning historian who has dived into a recent release of files previously buried in the US National Archives collection relating to the assassination of John F Kennedy.
“There is this sort of dual reality where, across the government, there are hundreds of people who know this exists yet it is never publicly exposed,” Mr Garrow told The Independent.
“At that time there was an ethic in the US that prominent men’s private affairs didn’t qualify as news. That was what also protected JFK.”
He believes the FBI files show the intelligence operation targeting King was almost unparalleled, rivalled only by the surveillance of Elijah Muhammad, the leader of the Nation of Islam, and the US Communist Party.
However, most of it never saw the light of day. In the end Hoover resorted to ordering an agent to send King the notorious “suicide letter” which threatened to expose his “filthy, abnormal” behaviour and urged him to kill himself before Christmas.
The letter was sent anonymously by one of Hoover's deputies, posing as a disaffected activist, in the weeks before King received for the Nobel Peace Price in December 1964.
By that time, King had become globally famous as the symbolic leader of the American civil rights movement after spearheading nonviolent demonstrations such as the year-long Montgomery bus boycott and the 1963 campaign of sit-ins and marches in Birmingham in protest over racial segregation in the Alabama cities.
Between 1957 and 1968, he travelled more than six million miles to give more than 2,500 speeches and take part in protests across the US - including the huge March on Washington, where he delivered his historic "I Have a Dream" address in which he called for an end to racism.
But the FBI tapes may lead to reassessment of a man whose Christian faith was credited with inspiring his belief in peaceful civil disobedience.
Michael Mosbacher, the acting editor of Standpoint magazine, which is publishing Mr Garrow’s article about the files, said the files reveal MLK as “the Harvey Weinstein of the civil rights movement”.
“If public figures are now all – rightly – subject to scrutiny, there should be no exception for Martin Luther King, however worthy his other activities were,” he writes in the June issue.
Mr Garrow agreed it was time for a reevaluation of the civil rights leader. “In the future we are going to see Dr King as a more privately troubled figure that we previously appreciated,” he said.
“The discussion will be, how great a private price did he pay because of his unwanted celebrity?”
King was, as he himself recognised, a “Jekyll and Hyde” figure, sad Mr Garrow. He may even have been a manic depressive who was regularly hospitalised with exhaustion and indulged in binge drinking.
“King was relentlessly self-critical,” the historian said. ”This is not someone who is glorying in being famous. He was incredibly tough on himself and absolutely realised his own shortcomings.”
That is not to excuse his alleged behaviour. “I am deeply sympathetic to King – but at the same time rape is rape,” added Mr Garrow.
The recording of the alleged rape, supposedly taken in the Willard Hotel in January 1964, also exposes the attitude of the FBI to women and sex in the 1960s.
Its typed summary reads: “The group met in his room and discussed which women among the parishioners would be suitable for natural or unnatural sex acts.
“When one of the women protested that she did not approve of this, the Baptist minister immediately and forcibly raped her.”
A handwritten memo, probably added by the FBI’s head of intelligence operations, adds: “King looked on, laughed and offered advice.”
The agents listening to the incident apparently did not consider intervening or even following up with the woman to see if she wanted to make a complaint.
“I think at least in the US context the mistreatment of black women was passed over more easily,” said Mr Garrow.
His article’s revelations, which were first reported by The Sunday Times, have so far met with silence from the US media, the King Center (formerly the Martin Luther King Foundation) and MLK’s family.
Civil rights activist, Edith Lee Payne, who was in the crowd for the famous 1963 “I Have A Dream” speech, told the Daily Mirror that the claims were based on “false information” and accused Mr Garrow of attacking King to gain “personal attention”.
“To suggest that [Martin Luther King Jr] would knowingly or willingly engage in anything illicit or criminal would discredit everything he sacrificed for, stood for and ultimately died for,” she added.
Another King biographer, Peter Ling, said his extramarital affairs were well-documented but he would be cautious about trusting the accounts of FBI agents who were seeking to "destroy" the civil rights leader.
The American studies professor at Nottingham University told The Independent: "My experience has been that there are some transcripts of FBI surveillance but no actual tapes released so we are dependent on their reporting and whether we can trust it since its purpose was to gather negative intelligence on MLK. I did not know about the rape incident that King is alleged to have witnessed without intervening.
"I believe there is enough evidence out there to indicate that King did have sexual liaisons that involved casual encounters and longer term relationships, but I am extremely wary of trusting the FBI to give me accurate information on a man whom Hoover wanted to destroy."
The tape recording, which is resting under court seal in a National Archives vault, will not be released until 2027.
Mr Garrow believes it should be made public. He said: “It will be a crime against history for these things to be destroyed, so I think it is imperative.”
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