Actually, evil Kirk viciously assaulted quite a few crewmen and reconstituted Kirk was never held accountable. Of course Rand wouldn't be able to agree not to press charges if she was dead... Scotty got off pretty lightly too.
Fictional characters do lots of harmful things under various mind-altering influences, but they're generally forgiven if they don't go too far. My point is that having it actually result in the death of another series regular is crossing a line, because it would taint the character irreversibly. It's not someplace a storyteller would want to take a series regular unless they were doing a much darker series than Star Trek.