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Does the death penalty save lives? In recent years, a new round of research has been using annual time-series panel data from the 50 U.S. states for 25 or so years from the 1970s to the late 1990s that claims to find many lives saved through reductions in subsequent homicide rates after executions. This research, in turn, has produced a round of critiques, which concludes that these findings are not robust enough to model even small changes in specifications that yield dramatically different results. A principal reason for this sensitivity of the findings is that few state-years exist (about 1 percent of all state-years) in which six or more executions have occurred. To provide a different perspective, we focus on Texas, a state that has used the death penalty with sufficient frequency to make possible relatively stable estimates of the homicide response to executions. In addition, we narrow the observation intervals for recording executions and homicides from the annual calendar year to monthly intervals. Based on time-series analyses and independent-validation tests, our best-fitting model shows that, from January 1994 through December 2005, evidence exists of modest, short-term reductions in homicides in Texas in the first and fourth months that follow an execution—about 2.5 fewer homicides total. Another model suggests, however, that in addition to homicide reductions, some displacement of homicides may be possible from one month to another in the months after an execution, which reduces the total reduction in homicides after an execution to about .5 during a 12-month period. Implications for additional research and the need for future analysis and replication are discussed. [ABSTRACT FROM AUTHOR]

Research Summary Social scientists have debated about whether the death penalty and/or executions deter homicides and thus save lives for at least half a century. Recent empirical analyses by Kovandzic, Vieraitis, and Boots (2009) and Land, Teske, and Zheng (2009) implied that if a deterrent effect of executions exists, it is small in magnitude and relatively short term. Discussions of Kovandzic et al. (2009) by Donahue (2009) and Rubin (2009) led to the question studied in this article: Do executions impact felony and non-felony homicides similarly? To address this question and build on recent studies, monthly time-series data on counts of executions and felony-type and non-felony-type homicides in Texas for the years 1994-2007 are analyzed. The results indicate a modest reduction, a deterrence effect, of approximately 1.96 non-felony-type homicides in the month after an execution followed by a rebound in the following second month with a net effect of 1.4 during a 12-month period. By comparison, the corresponding analyses of the felony-type homicide events series produce an estimated increase, a brutalization effect, in the month after an execution of approximately 0.5 homicide events. Combining these two counterbalancing effects produces a slight short-lived deterrent effect of an execution on all homicides taken together. This finding is consistent with the previous findings of Land et al.'s (2009) analyses of all homicides grouped together and with findings from prior studies of felony- and non-felony-type homicides. Policy Implications These findings provide additional evidence that the deterrent effects of executions are modest and short term. In addition, they imply that there would be little, if any, deterrence of homicides in Texas if executions were not used frequently. Recently however, Texas has been a state with (a) a large population, (b) a large number of capital murders and convictions, (c) a continuing stream of convicted murderers sentenced to death, and (d) a willingness to use executions extensively. Whether the modest, short-term deterrent effects of executions found in Texas occur in other states is an open question. But it is evident that few other U.S. states have these four characteristics. At the same time, the downside of the use of executions extensively in Texas is a partially counterbalancing brutalization effect-a slight, short-term increase in the frequency with which perpetrators of felony crimes such as robbery kill in the process of committing the crime. And none of this speaks to ethical or cost-benefit issues in the use of capital punishment as a public policy. [ABSTRACT FROM AUTHOR]