Can the joker be killed without impunity?
We always hear stupid batman stories where he tells someone whose about to cross the line "if you kill (whatever villian) I will hunt you down and bring you to justice". When you think about it thats one of the most empty threats possible. You could probably kill joker in broad daylight ala (kingdom come) and get off scott free. You could argue Joker poses a real and consitant threat since he keeps escaping arkham . The recent villian "nobody" could have murdered almost all of batmans rogue gallery and walked into the police station and confessed and I doubt would get any time.