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 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.
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.