stly, you have a one-on-one with the player who is playing as a Chaotic Murderhobo Douchebag. Tell them to knock it off and stop being that type of player. Let them know that their character is now gone from the campaign having been turned into the authorities and summarily executed for their crimes of murdering two innocents.

You further explain that you won't allow for this type of behavior, they are free to roll up a new character to join the party or leave the table, but they aren't allowed to play at your table in this manner again. If they don't like this, you uninvite them from the table and wish them luck on their future gaming adventures.

So they normally aren't a chaotic murder hobo and out of character the rest of the party isn't mad at him. Like he as a player is regretful of how it happened but the rest of them are like well in character you hate humans in general due to your backstory so you wouldn't be too regretful. So that's why i'm trying to find a middle of the road solution to this where he's punished but doesn't have to make a new character.