Does the Death Penalty Deter Crime? Studies are Inconclusive

We still don’t know enough about whether the death penalty works to deter crime, and policymakers should ignore research that claims to say whether it does, the National Academy of Sciences said on Wednesday.

A panel of experts appointed by the independent, nonprofit academy reviewed more than 30 years of research done since the 1976 Supreme Court decision that reinstated the death penalty as constitutional.

“The studies have reached widely varying, even contradictory, conclusions. Some studies conclude that executions save large numbers of lives; others conclude that executions actually increase homicides; and still others conclude that executions have no effect on homicide rate,” according to the academy panel, chaired by Daniel Nagin, an expert in criminology and statistics at Carnegie Mellon University. 

The National Academy of Sciences advises the federal government and other groups, often trying to provide the “last word” on important issues.

“The committee concludes that research to date on the effect of capital punishment on homicide is not informative about whether capital punishment decreases, increases, or has no effect on homicide rates,” it added. “Consequently, claims that research demonstrates that capital punishment decreases or increases the homicide rate by a specified amount or has no effect on the homicide rate should not influence policy judgments about capital punishment.”

The report turns up some interesting facts – for instance, only 15 percent of people who have been sentenced to death since 1976 have actually been executed. The study was commissioned by the National Institute of Justice, the research, development, and evaluation agency of the Justice Department; the Tides Foundation, which promotes “social justice”  by helping set up nonprofits; and the human rights-oriented organization Proteus Action League.

Get the latest news and analysis delivered to your inbox. Sign up for National Journal's morning alert, Wake-Up Call, and afternoon newsletter, The Edge. Subscribe here.