5 people are dead. Even looking beyond whether he is too evil or too crazy. You murder 5 people, you don’t deserve to be free again. Deserve is a massive component of Justice that certain types want to disregard completely.
Also, you can make the “they don’t believe/know what they did was wrong” argument for anybody. Why do they need to be jabbering on about werewolves and vampires to have diminished responsibility? Hate or fear of a person can trigger the same exact “kill or be killed” response. Almost every murderer has a justification that makes them lose sight of right or wrong while in the act.
And of course, they always stay crazy long enough to beat the charges then they can’t get released from the psychiatric hospital fast enough.
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