But now comes a report of another career turn, this one little known, that is triggering new buzz about the much-criticized Warren Commission investigation of John F. Kennedy's assassination 50 years ago.
In a new book on the commission, Coleman is quoted describing a three-hour interview he had had in the summer of 1964 with Cuban dictator Fidel Castro on a yacht off the coast of Cuba.
At the time, Coleman was a 43-year-old staff lawyer with the commission, and his assignment was to look into whether a foreign government had been involved in the Kennedy assassination.
Coleman, 93, says in A Cruel and Shocking Act, by former New York Times reporter Philip Shenon, that representatives of the Castro government indicated to the commission that Castro was eager to offer assurances he had nothing to do with the killing.
Among theories being pursued at the time was the possibility that Castro wanted to retaliate for the failed U.S.-backed Bay of Pigs invasion of Cuba in 1961. Commission members speculated among themselves at the time that if there were evidence of Cuban involvement, it most certainly would lead to war.
"I am not saying he didn't do it," Coleman is quoted as saying. "But I came back and I said that I hadn't found anything that would cause me to think there's proof he did do it."
Coleman could not be reached for comment Thursday.
The report has set off a small-scale dispute. While the book's disclosure of Coleman's meeting with Castro has been portrayed as a first, author Anthony Summers says he reported in 1994 that Coleman claimed to have met with Castro. Summers said in a blog post that Coleman later retracted that account, making the claim unreliable.
"Making the Castro meeting claim twice (to me), then retracting it, then making it anew (to Shenon) makes Coleman a less-than-reliable witness. . . .," Summers said in the blog post.
Shenon said he had no reason to doubt Coleman's credibility. He approached Coleman on the subject after hearing from other commission staff members that Coleman might have had the meeting. He said Coleman explained that he had not disclosed the information before because he believed it was classified.
Coleman says he met Castro and became friendly with him long before the Kennedy assassination, in the late 1940s, when he was a lawyer in New York with the firm of Paul, Weiss, Rifkind, Wharton & Garrison.
Coleman would practice law during the day and head to the jazz clubs of Harlem at night, where many of the era's great black entertainers would perform after finishing their shows at segregated clubs downtown. It was at these shows, Coleman says, that he met and struck up a friendship with the young Castro, also a jazz lover and on a visit to New York.
Coleman said that Castro recognized him as soon as he climbed aboard the dictator's yacht.
"He certainly knew that I'd met him up in New York," Coleman says. "It was a pretty animated conversation."
In addition to its descriptions of Coleman's activities on the commission, the book also includes an extensive account of the work of the late Arlen Specter as a young staff lawyer for the commission. Specter, who would later go on to become a U.S. senator from Pennsylvania, was 33 when he was plucked from his job as an assistant Philadelphia district attorney to serve on the Warren Commission, where he developed the so-called single-bullet theory.
The theory was an effort to explain how the assassin, Lee Harvey Oswald, could fire his 6.5-millimeter Carcano rifle so quickly that he hit Kennedy twice and Texas Gov. John Connally once. Specter posited that one of the shots had hit both Kennedy and Connally.
In the book, Specter expresses admiration for the "decency" of Earl Warren, the chief justice of the United States, who chaired the commission, but little regard for his legal abilities.
"Warren wasn't much of a lawyer," Specter is quoted as saying. "He wasn't brilliant. He wasn't even really smart."