I hear what you are saying, but there is a pretty large disparity of force here. He's 71 years old and a 6'4" dude got hyper aggressive, hopped the seats, got in his space and started making contact (allegedly).
I know we are all Monday morning quarterbacking this but at that age how many hits do you take before you shoot? IF contact has already been made, then do you wait for a more severe blow? He's a retired police chief, perfect record, never used his firearm in the line of duty. Combine his reputation with the video showing that he didn't even stand up and I am inclined to believe him. I bet at least one Juror would too.
I agree. That's why assault on senior citizens carry a harsher punishment. I'm not choosing sides either, just thinking that the guy has a chance to walk. The testimony of the off duty deputy will go along ways as well, don't know what he's saying though.