Twenty-three years ago, I was in Washington’s Mayflower Hotel, talking with a man named Frank Ragano, whose memoir of sorts, “Mob Lawyer,” contained a sensational claim about the assassination of President John F. Kennedy. (By sheer chance, no doubt, Richard Helms, the former director of Central Intelligence, was two tables away.) In the book, co-written with the veteran Times reporter Selwyn Raab, Ragano revealed that a client, a Florida Mafia boss, Santo Trafficante, Jr., had admitted being in on the assassination plot. Although attorney-client privilege extends beyond the grave, Ragano ignored that (and whatever claim the Mafia code of silence—omertà—may have had on him) by recounting what he claimed was Trafficante’s admission, uttered in Sicilian, four days before his death, in 1987: “Carlos è futtutu. Non duvevamu a Giovanni. Duvevamu ammazzari a Bobby.” (“Carlos fucked up. We shouldn’t have killed John. We should have killed Bobby.”) “Carlos” was the New Orleans Mafia boss Carlos Marcello; Bobby was Robert F. Kennedy, who was his brother’s Attorney General. According to Ragano, the motive was a quid pro quo: the mob killed Kennedy as a favor to Jimmy Hoffa, the Teamsters boss, and a target of Bobby Kennedy’s Justice Department. In return, the Mob got access to Teamsters’ pension fund, then worth about a billion dollars. It was all about the money, Ragano told me as we sat at the Mayflower—“forget everything else.” Ragano died, of natural causes, four years after his book came out, and there’s no real evidence to substantiate his story.