Basically, someone or few people armed with any weapons invade your home at midnight, and you whip out a shotgun to get the jump on them. Assuming you haven't killed them on the spot and force them to relinquish their weapons and get on their knees, should it REALLY be considered a crime to kill them in these instances?
I've read on stories where these scenarios did happen (the execute part) and, while the person that killed his assailants don't really ever get crazy punishments, they still go to jail for a time. Like, why?