The killer of JFK’s assassin died just weeks before he could speak out in a second trial (from Yahoo News UK.)
After killing Lee Harvey Oswald on national television, Ruby, the owner of a Dallas nightclub, usually denied that he was part of any conspiracy. On other occasions he intimated that he might have a different story. In June 1964, he asked Chief Justice Earl Warren to bring him to Washington to testify; Warren refused.
Ruby said once that he killed Oswald to spare Jackie Kennedy the pain of a criminal trial. That story was made up, said Gail Raven, a Texas woman who was friends with Ruby in 1963.
See: Ex-flame says Jack Ruby ‘had no choice’ but to kill Oswald (March 21, 2013).
Raven also said Ruby actively disliked Attorney General Robert Kennedy.