WASHINGTON, D.C. — A deep-dive research report, “What to Know,” by the Death Penalty Information Center (DPIC) examines one of the central justifications for capital punishment in the United States — deterrence — and concludes that decades of research have produced no credible evidence that the death penalty reduces homicide rates.
The March 2026 “What to Know” report on general deterrence highlights major scientific questions about the death penalty and its overall impact on reducing violent crime. According to the report, “decades of research have failed to produce credible evidence that use of the death penalty has an impact on homicide rates.”
According to the report, an overwhelming number of scholars who study capital punishment have reached similar conclusions regarding skepticism toward the death penalty. For example, the report finds that “88% of the nation’s leading criminologists said they did not believe the death penalty deters homicides,” and also adds that only “9% agreed that the death penalty significantly reduces the number of homicides.”
According to the Death Penalty Information Center report, researchers have not found a relationship between murder rates and whether or not a state allows the death penalty. The consensus was, “When states have abolished the death penalty, murder rates have not followed any consistent pattern of change.”
Instead, as mentioned in the report, homicide trends in those states typically “follow national trends rather than spiking or falling after abolition.”
As the DPIC report cites, one of the most influential studies on the issue was conducted in 2012 by the National Research Council. The council produced decades of research on post-Gregg v. Georgia (1976) trends, which reinstated the death penalty under specific revised sentencing procedures.
This research from the National Research Council, as stated by the Death Penalty Information Center research report, concluded that “existing studies on deterrence ‘are not informative about whether capital punishment decreases, increases, or has no effect on homicide rates.’” The report also explicitly recommends that these studies “‘not be used to inform deliberations’ about the death penalty.”
According to the DPIC, the National Research Council report offered three distinct research recommendations for future researchers to follow, something its 1978 predecessor report reportedly did not do. It recommended that future researchers “collect stronger data on capital and non-capital components of the punishment scheme for homicides; study how potential murderers actually perceive and respond to the risk of sanction, rather than assuming response to objective statistics; and use statistical methods that rely on ‘less strong and more credible assumptions.’”
In a similar tone, Bill Klapper, a Wyandotte County District Court judge, said in April 2025, “The scientific community has found no reliable evidence of the death penalty being a deterrent to homicides…Murder rates are and have been independent of the imposition of the death penalty or the institution of having a death penalty.”
Other examples brought to light by the Death Penalty Information Center’s “What to Know” report include comparisons to other countries’ low homicide rates despite not enacting any form of capital punishment.
A crucial example of this can be seen in the European Union, where “all member countries have abolished the death penalty, every country has a lower murder rate than the United States.”
In addition to this, research also found that, as of 2018, “of the eleven countries that had abolished the death penalty between 2008 and 2018, ten experienced a decline in murder rates post-abolition.”
While the debate over the effectiveness of the death penalty and its justifications has been a point of controversy for decades, key research has concluded that the death penalty as a form of deterrence for violent crimes may not be an effective method, as reported by the “What to Know” research report.
Follow the Vanguard on Social Media – X, Instagram and Facebook. Subscribe the Vanguard News letters. To make a tax-deductible donation, please visit davisvanguard.org/donate or give directly through ActBlue. Your support will ensure that the vital work of the Vanguard continues.
