Well, maybe someone should tell the writers this because they're the ones who keep bringing this up.
The ineptitude of the justice system is already acknowledged. It's why the superheroes exist in the first place.Plus instead of putting the blame all on them, put some of the blame on the crappy legal systems. Batman hands the villains over to the police, but the courts never give them the death penalty. After a point the blame isn't just his. Hell, Maggie Sawyer shot the Joker full of bullets in Gotham Central and the bastard still survived. Status quo is God is working against all of them.