Deterrence

Capital Punishment and Police Safety

A Death Penalty Information Center analysis of U.S. murder data from 1987 through 2015 has found no evidence that the death penalty deters murder or protects police. Instead, the evidence shows that murder rates, including murders of police officers, are consistently higher in death-penalty states than in states that have abolished the death penalty. And far from experiencing increases in murder rates or open season on law enforcement, the data show that states that have abolished the death penalty since 2000 have the lowest rates of police officers murdered in the line of duty and that killings of police account for a much smaller percentage of murders in those states.

The data show that non-death-penalty states, "transitional states" (that is, states that abolished the death penalty during the period covered by the study), and death-penalty states with the lowest rates of execution had the lowest officer-victim rates.
The data show that non-death-penal­ty states, tran­si­tion­al states” (that is, states that abol­ished the death penal­ty dur­ing the peri­od cov­ered by the study), and death-penal­ty states with the low­est rates of exe­cu­tion had the low­est offi­cer-vic­tim rates.
The data show that police officers were murdered at higher rates in states that had the death penalty than in states that did not. States that later abolished the death penalty had by far the lowest officer-victimization rates.
The data show that police offi­cers were mur­dered at high­er rates in states that had the death penal­ty than in states that did not. States that lat­er abol­ished the death penal­ty had by far the low­est offi­cer-vic­tim­iza­tion rates.
Officer victim rates followed roughly the same trends over time, whether or not states had the death penalty and, overall, officers were murdered at lower rates in non-death-penalty states than in states that had the death penalty throughout the study period. Click on the image above for a slide show of the findings of DPIC's murder-rate study.
Officer vic­tim rates fol­lowed rough­ly the same trends over time, whether or not states had the death penal­ty and, over­all, offi­cers were mur­dered at low­er rates in non-death-penal­ty states than in states that had the death penal­ty through­out the study peri­od. Click on the image above for a slide show of the find­ings of DPIC’s mur­der-rate study.
To see if the death penalty had a special deterrent value in protecting police officers, DPIC compared murders of police as a percentage of all murders in states with the death penalty, non-death-penalty states, and states that abolished the death penalty at some point during the study period. The percentages of murders in which police were victims was virtually identical in death-penalty states and non-death-penalty states. However, the percentage of murders that involved police as victims was far lower in states that later abolished the death penalty.
To see if the death penal­ty had a spe­cial deter­rent val­ue in pro­tect­ing police offi­cers, DPIC com­pared mur­ders of police as a per­cent­age of all mur­ders in states with the death penal­ty, non-death-penal­ty states, and states that abol­ished the death penal­ty at some point dur­ing the study peri­od. The per­cent­ages of mur­ders in which police were vic­tims was vir­tu­al­ly iden­ti­cal in death-penal­ty states and non-death-penal­ty states. However, the per­cent­age of mur­ders that involved police as vic­tims was far low­er in states that lat­er abol­ished the death penalty.

In a 2017 Discussions With DPIC podcast, “Does Capital Punishment Deter Murder?,” DPIC Fellow Seth Rose and Executive Director Robert Dunham explore the assertions long made by death-penalty proponents that capital punishment advances public safety by deterring murders and by protecting police officers. “There’s no evidence that the death penalty deters murder and there’s no evidence that it protects the police,” Dunham says. “Murder rates may be affected by many things, but the death penalty doesn’t appear to be one of them.” While the rate at which police officers are killed drives the political debate about the death penalty, the numbers suggest that the death penalty makes no measurable contribution to police safety.