As per a 1992 law placing a 25-year deadline on the release of classified CIA and FBI documents pertaining to the assassination of President John Fitzgerald Kennedy, the National Archives has released a set of 3,810 files that have kept historians and JFK assassination researchers busy, combing the documents for anything that might provide further insight into Kennedy’s death. Although the files that have been released (with another 3,100 due by October) have not provided any game-changing evidence in regards to a possible conspiracy connected to Kennedy’s murder, they do offer new insight into skepticism that developed within the CIA about how the official investigation was conducted — and their possible role in prompting Oswald to plot to kill the president.
Despite the CIA having publicly backed the findings of the Warren Commission, in that Lee Harvey Oswald was the only person involved in Kennedy’s death, with no evidence of a broader conspiracy involved, internal documents show that by the mid-1970s Central Intelligence was concerned that the Warren Commission failed to investigate the issue of Oswald’s foreign contacts, specifically those involved with his meeting at the Cuban consulate in Mexico with diplomats from Havana. This meeting also included a Soviet diplomat that was also a known KGB assassinations expert — and the CIA couldn’t rule out the possibility that the officials Oswald met with may have encouraged him to execute his plan to assassinate Kennedy.
The document also questioned the CIA, FBI and Warren Commission’s failure to question Silvia Duran, a Mexican employee that worked at the Cuban consulate, who reportedly had an affair with Oswald during his visit. According to the document, she was the "sole live witness on the record regarding Oswald’s activities." However, her testimony "was taken and presented, solely, by the Mexican governmental authorities." Duran is still alive today, but insists she did not have an affair with Oswald, although she does acknowledge that she helped him with his unsuccessful Cuban visa application.
The CIA had also kept a number of secrets from the Warren Commission, including their then-secret involvement in various assassination attempts on Cuban President Fidel Castro. CIA and FBI officials repeatedly lied to the Warren Commission in order to keep these classified issues secret, described as a "benign cover-up" by an in-house historian with the CIA in 2013. CIA documents speculate further on the possibility that news of these attempts on Castro’s life might have inadvertently contributed to Oswald’s suspected motive for killing Kennedy, as Oswald was an admirer of Castro.