Oswald Innocence CampaignJohn D. Sarviss That was a mistake on the part of the plotters. They knew that Ruby had a partially amputated index finger, and they thought it was on his right hand, his trigger finger. So, that's why they went with the middle finger in the ruse. But in reality, it was Ruby's left index finger that was partially amputated. So, Ruby would have shot with his index finger. Any excuses why he supposedly shot with his middle finger are pure, unadulterated bull shit, as George Carlin used to say.