Capital punishment has been abolished in all Australian States since the mid 1980s. The United States of America is the only Western democracy that has retained the death penalty. The aim of this bulletin is to analyse and summarise the empirical evidence on the deterrent effect of capital punishment. It provides a survey of the results of 74 research projects published between 1952 and 2003. These projects employed a variety of methodologies, including economic modelling, and covered a range of geographical areas and time periods mainly in the United States. The majority of the studies show that the use of capital punishment did not deter the commission of homicide; this remains the case when studies that used relatively unsophisticated research designs were excluded. The bulletin concludes that three decades of deterrence research since Ehrlich’s (1975a) economic model has failed to deliver conclusive evidence on the deterrent effect of capital punishment.