There is separate issue to discuss. They say the shooter used his middle finger to fire the gun. But, why is that finger straight and extended all the way through the trigger guard? Why isn't it wrapped around the trigger as you would do with your index finger?
And note that the official story has it that Ruby tried to shoot the gun again immediately. But, how was he going to fire it like that with his middle finger straight? And why was it straight? What was the practical reason for doing that?
Of course, there isn't any practical reason. So, why does it look like that? Notice that that middle finger is a slightly different shade than the rest of the hand. It's a little lighter. So, is it something they added to the photo? Why would they do that?
Well, I think they wanted the middle finger to stand out. They didn't want it to be overlooked. If it was just curled around the trigger, with his distal interphalangeal joint on the trigger, it might not have been noticed. And they wanted it to be noticed because they felt that it really marked the guy as being Jack Ruby. Who else but Jack Ruby with his amputated index finger would shoot with his middle finger? It was like leaving his signature. But alas, they were mistaken. It was his left index finger that was partially amputated. But, they didn't know that. Someone gave them the wrong information. And they thought this was a bonanza for them: the hallmark of Jack Ruby, that he had to fire the gun with his middle finger. But, it's actually a disaster for them because Jack Ruby had an intact right hand and would definitely not have fired the gun with his middle finger. So really, they blew it. They blew it big-time. Shooting with his middle finger is something Jack Ruby had no reason to do and would not have done; not instinctually, not intuitively, not by accident, and not on purpose.