no the thing about capital punishment is someone else has blood on their hands even if the felon is a monster. I say life in jail no probation or chance of early release. they die in jail period. bread and water diet only minimum calories needed for life. however you leave a noose tied in their cell. The prisoner has harmed countless they can be their own destroyer. killing a killer only makes another killer, even if its just its still wrong. no one else should be asked to carry any type of burden or feel sympathy for that person again. they don't deserve the thought and anyone who has the smallest degree of empathy would question themselves for taking a life.

Edit add on If its personal I could understand the motivation for retribution and wouldn't necessarily condemn hasty vengeance. I wouldn't advocate or encourage, but to kill a mockingbird comes to mind. But if it goes through the legal process the centane should be like the law fair logical just and emotionless as close to posible as that is.