If someone is so inhuman and so brutal and don't regret to their acts , then for setting an example for society it is correct. Otherwise making someone regretful for their act is correct thing, and motto behind giving punishment is to make person realise his/her crime. For making and healthy and livable society.

@wtfjudith Yes. To the crimes like rape, mass murder, terrorist attack, un-natural torture etc There should be a death penalty. Sometimes fear bring discipline amongst the people.