Imagine you are a "superhero". You are above the law and no one can stand against you. How would you handle your crime-fighting? Would you pass judgement on criminals yourself, simply hand them over to the authorities, or take a different approach?
I would act as a vigilante and handle criminals myself. I would kill those who devoted their lives to causing the suffering of others or those who consistently brought suffering to those around them. As with all all rules, their would be exceptions, but I would do my best to avoid them.