Of course one alternative to this is to restore capital punishment, but I'm not sure I would be for that. I'm not sure it's right to take an eye for an eye.
Draco Malfoy, who was Snape's favorite student, kept flicking puffer-fish eyes at Ron and Harry, who knew that if they retaliated they would get detention faster than you could say " Unfair."
It was an antiquated system which sought to inflict punishment for every mortal thing—it was the lex talionis of the Old Testament, an eye for an eye and a tooth for a tooth.