The Warren Commission found no evidence linking Ruby’s killing of Oswald with any broader conspiracy to assassinate Kennedy.[20] In 1964, the Warren Commission provided a detailed biography of Ruby’s life and activities to help ascertain whether he was involved in a conspiracy to assassinate Kennedy.[50] The Commission indicated that there was not a “significant link between Ruby and organized crime”[51] and said he acted independently in killing Oswald.[52][20]: 373–374
Warren Commission investigator David Belin said that postal inspector Harry Holmes arrived unannounced at the Dallas police station on the morning that Ruby shot Oswald and, upon invitation by the investigators, had questioned Oswald, thus delaying his transfer by half an hour.[53] Belin concluded that, had Ruby been part of a conspiracy, he would have been downtown 30 minutes earlier, when Oswald had been scheduled to be transferred.[53]
In Gerald Posner’s book Case Closed: Lee Harvey Oswald and the Assassination of JFK , Ruby’s friends, relatives and associates claimed that he was upset over President Kennedy’s death, even crying on occasions and closing his clubs for three days as a mark of respect.[54] They also disputed the conspiracy claims, saying that Ruby’s connection with gangsters was minimal at most and that he was not the sort of person who would be entrusted with an important assassination as part of a high-level conspiracy.[54]
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Dallas reporter Tony Zoppi, who knew Ruby well, claimed that one “would have to be crazy” to entrust Ruby with anything as important as a high-level plot to kill Kennedy since he “couldn’t keep a secret for five minutes … Jack was one of the most talkative guys you would ever meet. He’d be the worst fellow in the world to be part of a conspiracy, because he just plain talked too much.”[54]: 361, 399 He and others described Ruby as the sort who enjoyed being at “the center of attention”, trying to make friends with people and being more of a nuisance.[54]
Some writers, including former Los Angeles District Attorney Vincent Bugliosi, dismiss Ruby’s connections to organized crime as being highly minimal: “It is very noteworthy that without exception, not one of these conspiracy theorists knew or had ever met Jack Ruby. Without our even resorting to his family and roommate, all of whom think the suggestion of Ruby being connected to the mob is ridiculous, those who knew him, unanimously and without exception, think the notion of his being connected to the Mafia, and then killing Oswald for them, is nothing short of laughable.”[56]
Bill Alexander, who prosecuted Ruby for Oswald’s murder, equally rejected any suggestions that Ruby was involved with organized crime, claiming that conspiracy theorists based it on the claim that “A knew B, and Ruby knew B back in 1950, so he must have known A, and that must be the link to the conspiracy.”[54]
Ruby’s brother Earl denied allegations that Jack was involved in racketeering Chicago nightclubs, and author Gerald Posner suggested that witnesses may have confused Ruby with Harry Rubenstein, a convicted Chicago felon.[54] Entertainment reporter Tony Zoppi was also dismissive of mob ties. He knew Ruby and described him as a “born loser”.[54]
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He also claimed he shot Oswald on the spur of the moment when the opportunity presented itself, without considering any reason for doing so.[43]: 199 Ruby told the FBI he was “in mourning” Friday and Saturday. He said he cried when he heard the President was shot, “cried a great deal” Saturday afternoon and was depressed Saturday night. He explained that this grief was caused by his great love for the President and his sympathy for the Kennedy family. The anguish over the assassination, Ruby stated, finally “reached the point of insanity”, suddenly compelling him to shoot when Oswald walked to the police ramp that Sunday morning.[58] At the time of the shooting, Ruby said he was taking phenmetrazine, a central nervous system stimulant.[43]: 198–199 Ruby broke into tears at his bond hearing in January 1964, as he talked to reporters regarding the assassination of President Kennedy. His voice breaking, Ruby said that he could not understand “how a great man like that could be lost”. According to an unnamed Associated Press source, Ruby made a final statement from his hospital bed on December 19, 1966, that he alone had been responsible for the murder of Lee Harvey Oswald.[59] “There is nothing to hide … There was no one else,” Ruby said.[[60]]