Rabbi Avigdor Miller, z’tl, held strongly and said time after time that the death penalty is a strong deterrent to murder. he also said many times that the best rehabilitation for a murderer is the electric chair.
he was incensed at the liberal attitudes of todays society because that itself was the cause of much of crime. i dont know if he read all the statistical reports but he was a man of great Chochma and felt one was a misguided fool to listen to the liberals who had mercy on criminals.
all of his statements were based soley on the Gemorah and the Mesorah.