Variation in executions and abolition of the death penalty by year and state in Australia was used to examine the deterrent effect of the death penalty on homicides. A dataset covering 1910-2010 was collected comprising homicide rates and controls for demographic and criminal justice features. Using OLS, there was no evidence that executions have a deterrent effect. There is some evidence of a deterrent effect of capital punishment laws, but the effect is no longer significant once demographic and criminal justice variables were added to the model. However, when using exogenous variation in party-political representation to address endogeneity issues, no evidence of a deterrent effect of capital punishment was found.