Here a Dallas PD detective talks about the curious behavior of Jack Ruby immediately following the Oswald assassination.
Does this strike you as:
a. a man in search of swift justice for Jackie Kennedy?
b. a man who didn’t want to be tortured and murdered by his organized crime associates for non-compliance on an offer he could not refuse (like Sam Giancana told his younger brother, Chuck, in Double Cross)?
Someone Would Have Talked by author Larry Hancock mentions that Jack Ruby’s post-assassination phone records indicated that he placed at least one telephone call to an individual in Los Angeles by the name of Al Gruber, and that Gruber or the people he represented may have assigned Ruby (under threat of torture and murder for non-compliance) to kill Oswald to seal the conspiracy.
book links below: