The Death Penalty and Deterrence

Check out this op-ed by Cass Sunstein and Justin Wolfers on the death penalty and deterrence.  (We've discussed -- here and here, for example -- Sunstein's claims about these matters before here at MOJ.)  Here's the basic point:

A prominent line of reasoning, endorsed by several justices, holds that if capital punishment fails to deter crime, it serves no useful purpose and hence is cruel and unusual, violating the Eighth Amendment. This reasoning tracks public debate as well. While some favor the death penalty on retributive grounds, many others (including President Bush) argue that the only sound reason for capital punishment is to deter murder.

We concur with Scalia that if a strong deterrent effect could be demonstrated, a plausible argument could be made on behalf of executions. But what if the evidence is inconclusive?

We are not sure how to answer that question. But as executions resume, the debates over the death penalty should not be distorted by a misunderstanding of what the evidence actually shows.

I agree.  And, I think this is advice that those who write on crime and punishment for the Catholic bishops should take to heart.  That is -- as I explain here -- I worry about pastoral teaching on capital punishment that makes too much depend on contestible claims about deterrence.