An Honest Politician’s Guide to Deterrence: Certainty, Severity, Celerity, and Parsimony

Abstract

Conclusions by economists and other social scientists about the deterrent effects of punishment were long discordant, economists finding that increases in punishment produce marginal deterrent effects and other social scientists typically finding either that they do not or that any effects found are too small and contingent on particular conditions to have policy relevance. That discordance has now ended, with both now accepting the “no, too small, or too contingent” finding. In Beccaria’s classic terms, there is now agreement that the effects of certainty and immediacy are much more important than the effects of severity. A substantial literature shows, however, that particular police deployments can reduce the incidence of crime. An important policy lesson is that resources should be diverted from imprisonment to policing. Another is that sentencing laws and practices should be substantially recast to reduce the severity of punishment and with that the sizes of the prison population and public spending on imprisonment. Saved funds can be used to reduce public spending generally, reallocate money to other unmet public needs, and invest more in policing and community corrections.