2006): “The Deterrent Effect of Capital Punishment: Evidence from a Judicial Experiment

We use panel data for 50 states during the 1960–2000 period to examine the deterrent effect of capital punishment, using the moratorium as a ‘‘judicial experiment.’ ’ We compare murder rates immediately before and after changes in states ’ death penalty laws, drawing on cross-state variations in the timing and duration of the moratorium. The regression analysis supplementing the before-and-after comparisons disentangles the effect of lifting the moratorium on murder from the effect of actual executions on murder. Results suggest that capital punishment has a deterrent effect, and that executions have a distinct effect which compounds the deterrent effect of merely (re)instating the death penalty. The finding is robust across 96 regression models. (JEL C1, K1) I