How did Batman kill the Joker?

How did Batman kill the Joker?

[roastedsand]

I always wonder, why all of those Villain Batman caught never get Death sentence

When they destroy lot of stuff, and kiIIed dozen of people, some of them even got out of prison and do the same crime over and over again

[alexrabacchi]

Batman: i report miself, i killed the joker
Gordon: officer, report. The joker broke his neck after shoot himself with two bullets in the head
Batman: he didn't shoot himself and there are no bullets...
Gordon loading his gun: give me 10 second

[ShieldHeroVeryBloodFairyFear]

But Superman still can hear what Jocker Talk In Car
He can hear after You move

[random-boi]

Better question
How many times did the Joker and the Robin army died