For me that's simply irrelevant, because how "bad" your enemy is doesn't give you any additional leeway. You can use violence to directly prevent greater violence, for example in self-defense. Throwing milk-shakes at someone achieves nothing. Even when a murderer is arrested, the cops don't get to spit at them while they wait for trial. It doesn't matter in the least how bad a person is. It's a red herring from the word go, due process and same rights for all is a very clear standard, and normalizing violating it because "others are worse", leaves us with nothing.