> Some argued that if the death penalty is eliminated, prosecutors will lose what little leverage they have to get murder suspects to cooperate with police.
This seems like a trivially testable hypothesis. Civilized countries outlawed the death penalty for murder a long time ago, do their murder suspects in fact simply refuse to cooperate with police since death isn't a possible penalty? I would assume the answer is "No".
Many European countries don't even have life-without-parole as a possible sentence. All criminals in those countries can in principle be paroled, it's just that if you're an unrepentant murdering nazi, the parole decision is really easy, "Hmm, do we want this nazi to kill a bunch more people as he's repeatedly insisted he will if given a chance? No".
This seems like a trivially testable hypothesis. Civilized countries outlawed the death penalty for murder a long time ago, do their murder suspects in fact simply refuse to cooperate with police since death isn't a possible penalty? I would assume the answer is "No".
Many European countries don't even have life-without-parole as a possible sentence. All criminals in those countries can in principle be paroled, it's just that if you're an unrepentant murdering nazi, the parole decision is really easy, "Hmm, do we want this nazi to kill a bunch more people as he's repeatedly insisted he will if given a chance? No".