well if he were going to jail for that, whats the point to have a licence for a gun? maybe in ur countries they dont give licence for own a gun for citizen, then ye he would be in trouble cos even defending himself would be a crime he own a gun and stuff.
The thing happened right like this:
the criminal came to the windows of car pointed him the gun and said get out of car, he opened door of car and left, when criminal sitted and started to drive, bum, bum, headshoot.
I think it will be like in USA, i doubt someone there would go to jail for doing same thing.