The only way Ruby would have done the hit in the 1st place was because they threatened to hurt/kill his family if he didn't play ball. That remained an outstanding threat up until his death. He was protecting them to the end. Otherwise, why lie about never knowing/meeting Oswald before? And how could he have known that Oswald was never in his club before? No way he could be sure of that. And what about his other interviews where he hinted that the powers that be were keeping him silent? He was trying way too hard to dispel any connections to a conspiracy. If there was no threat to him or his family, then why walk on egg shells when denying conspiracy rumors? And why would anyone believe htiman Ruby was a lone nut gunman who shot another lone nut gunman on a whim? That's 2 too many lone nuts for my liking.
