Homicide, punishment and deterrence in Australia

Abstract Australian data encompassing 1910–2022, by year and state, were analyzed to estimate the effect of capital punishment on homicide rates. Our estimates showed that capital punishment had a negative and significant effect on homicides. In some specifications, the estimates implied that an execution was associated with 12.68 fewer homicides; whereas in other specifications, each execution reduced the number of homicides by less than one. The results are stable across different model specifications and subsamples. However, we cannot reject the hypothesis that the deterrent effect of capital punishment being legal is the same as that of mandatory life sentences with mandatory minimum non‐parole periods. Thus, our results imply lengthy sentences serve as just as strong a deterrent as capital punishment.