One indication is that the information is based on testimonies and partly on some other findings, and the fact that the Federal Bureau of Investigation has buried the report for almost fifty years in the Kennedy murder case, although there is no reference to JFK.
Why this document was among those about the Kennedy's assassination or why it was marked by the National Archives and Records Administration's JFK Task Force in 1994 with an "x" for "total denial" of its release isn't clear.
Dr King was assassinated before the planned march.
Interestingly, however, the exhibition devotes several pages to the sexual life of the Nobel Peace Prize victor for his struggle to abolish the racial discrimination of a pastor, arguing that he had at least one illegitimate child and extra-marital relations, that his most famous mistress was famous singer and political activist Joan Baez, and that King was involved in sexual orgies.
The FBI said Dr King and his organization were "made-to-order" to achieve these objectives.
In reference to a February 1968 workshop to train ministers in urban leadership, the document reads: "One Negro minister in attendance later expressed his disgust with the behind-the scene drinking, fornication and homosexuality that went on at the conference".
"Several Negro and white prostitute [s] were brought in from the Miami area. A variety of sex acts deviating from the normal were observed".
It notes that two previous aides were party members and eight others, who helped shape Dr King's organisation in its early stages, had communist affiliations. Then Attorney Geberal Robert F. Kennedy had authorized phone tapping surveillance of King as part of the FBI's controversial domestic intelligence program.
It's about a secret mud campaign that wanted to damage the credibility of the King's movement, USA media comment. A Senate committee later confirmed that the letter, alongside recorded evidence of King's extramarital affairs, had been sent to King by the Federal Bureau of Investigation. President Trump had tweeted he wanted to release all of the files "in order to put all conspiracy theories to rest". The withheld documents have been placed under a six month review.
The most salacious claims about Dr King's sex life are contained in a dense collection of rumours in the final two pages.