Well he didn't deserve that!(spoilers)
Good movie - very original! But to give him the electric chair??
Lets look at the facts - he was attacked and killed a man in self defence. The only crime he was guilty of was blackmail, if that is a crime in the US?
Big Dave on the other hand beat a man to death and tried to kill another. He wasn't a nice guy and got what he deserved.
I know life isn't always fair, I suppose that I just didn't expect this ending. Still, a great movie!