That being said. Why doesn't the legal system in these universes have a death penalty? Mind you I am asking from an In-universe practical standpoint, not a marketing or profit standpoint. Almost all of these universes have a poor track record of criminal containment and a worse record of reforming criminals. If anything from a story perspective, governments seem to have less of a problem taking lethal measures towards dealing with heroes than villains.
The impracticallity of the no kill policy is kind of blatant in a super hero universe considering civilian casualties and property damage everytime a villain who is capable of escaping does so. Mind you I am not in favor of the death penalty in real life.
That being said, supervillains often do these crimes in full view of everyone, in a premeditated fashion. And vigilantes are everywhere already so I fail to see the arguments to not have a death penalty. Also it seems that anyone can be declaired legally insane and skip the court system. Can anyone tell me how the penguin counts as legally insane? He seems quite in control of his actions, bird motif or otherwise, and characters like the scarecrow initially were just unethical scientists, not insane. Also Sociopathy is not considered a valid grounds for legal insanity despite the fact that it's causes are biological.
I dislike how in the DC universe a hero's willingness to kill automatically means that they will go megalomaniacal. If Superman believes in due process then fine, he wouldn't be Superman if he didn't, but that still means that the legal system needs to step up to protect its citizens. If not, then it only makes sense that people would latch onto morally grey anti-heroes, who if nothing else send out a real warning to supervillains and corrupt governments.
