system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] Why is it that whenever a DC hero kills a villain, they always end up going down a path to villainy?

It's like no matter how justified they are in killing someone, they're automatically evil. They're shunned and reviled by their fellow heroes and are immediately destined to descend into madness and at times, dictatorship.

What gives?
gpt
They don’t.

Wonder Woman, for instance, executed Maxwell Lord and all she faced was some of her teammates being dicks and a quick trial that found her fully justified. No madness or evil, the entire time she was adamant that her actions were completely justified. To the point where she insisted on the trial, despite her very easily being able to tell them all to piss off.

Superman straight up executed Zod and his cohorts after they were de powered and suffered no fall from grace. Just nightmares.

Hawkman kills fairly regularly, Aquaman can and will put his enemies down, Green Arrow hunted down and murdered Prometheus for revenge, Damian Wayne has a decently sized body count given that he’s like 10, Jason Todd doesn’t use those guns for show, Starfire will vaporize an enemy if provoked enough, Flash has killed Zoom repeatedly(Which is how he learned the guy was immortal), and so on. Hell, Constantine has killed an entire Earth and remains a hero. Well, as heroic as he normally is.

Quite a few heroes kill, it just only becomes a big deal when said killing is when they are skipping down the path to evil.

Injustice, for instance, has Joker’s death as the START of Superman’s fall but hardly the cause. The cause was Lois’s death breaking the guy while Batman was being an absolute ass and that universe’s Wonder Woman was MUCH darker than the mainline one and was a terrible influence. It took quite some time for Superman to get corrupted to the point of casual execution, time and a full mental collapse.

Note that while BATMAN treats killing an enemy under any circumstances as the WORST THING EVER, Batman’s also nuts and way more hung up on the ‘No Killing’ rule than anyone else. In that he’s one of the very few heroes who actually has that has a hard rule. The rest are on the ‘We aren’t judge, jury, and executioner’ stance. Where executing an enemy is a big deal and not to be done on a whim. But also allowed in certain circumstances, such as protecting others.