There's a lot of speculation.
Jack Ruby got a lot of phone calls from a Chicago underworld contact in the month prior to the shooting.
Several "bums" were arrested in the area immediately after the shooting, yet there is no record of the arrest. They were well fed homeless people and cannot be accounted for.
The mysterious deaths of many of the witnesses cannot be explained. They have asked insurance actuaries, who are able to mathematically predict a death rate, to analyze the liklihood of the witnesses dying and the actuaries are unable to explain it. It is an incredible coincidence to have such a large number of people die accidently or otherwise.
JFK's father was supposed to be a target of the mob and reportedly entered Chicago in disguise to plead for his life to Sam Giancana.
It is an interesting topic that will never be fully explained.
"After all, we are not communists"
Christopher Moltisanti: You ever think what a coincidence it is that Lou Gehrig died of Lou Gehrig's disease?
Tony Soprano: Yeah well, when you're married, you'll understand the importance of fresh produce.
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