They've now been released, and Chicago names are popping up in the fine print.
On Thursday the National Archives made public nearly 1,500 documents related to the federal investigation into the 1963 shooting of President John F. Kennedy.
When the shots killed President Kennedy in a car in Dallas, Texas, the investigation that followed produced hundreds of thousands of records, transcripts, cables, pictures and films.
The long-awaited and long-locked up documents were ordered released by the White House. In the files are expected details of Lee Harvey Oswald's connections to the Soviet Union and Cuba.
Also in the document dump are new details about Chicago as a training ground for Cuban militiamen.
As the I-Team has reported over the years, Outfit bosses recruited crooked lawmen to train Cuban rebels with the goal of protecting their homeland from Fidel Castro, who was about to douse the mob's lucrative gambling mecca in the tropics.
At least nine files refer to Chicago circa 1963 and several individuals linked to the Outfit.
Most notably among them are former Chicago police officer and Cook County Deputy Sheriff Richard Cain.
Cain had deep connections to Chicago organized crime according to investigators, especially ruthless mob boss Sam "Momo" Giancana.
The JFK files cite Cain's involvement in recruiting young Cuban exiles in Chicago in what experts believe was a mob effort to keep control of Cuba and resulted in secret training in Cook County of a covert resistance force that never made it to Havana.
"Well, there's some belief that Cain might have been working with the CIA in terms of making himself relevant and meaningful and important, and to get something for Richard Cain. So, if he was involved in the CIA and attempts to get organized crime to assassinate Fidel Castro that then might be a short step to what might have to do with the JFK assassination," said Chicago mob expert and author John Binder.
What is not in the JFK fine print is a Chicago mob smoking gun. There is nothing to indicate the Outfit set up JFK's assassination.
But the new documents strongly reinforce what the I-Team has been reporting for years: that Chicago mob bosses had a keen interest in keeping Castro from taking over Cuba and extinguishing their gambling rackets.
If that was among Cain's failures, on December 20, 1973 he paid for them when he was killed in a gangland hit as he walked into a sandwich shop near the Loop.