The Incapacitation Effect of Incarceration: Evidence from Several Italian Collective Pardons
利用意大利1962至1990年间八次集体赦免导致的监狱人口突然大幅减少，估计监禁对犯罪的失能效应，发现犯罪对失能的弹性在-17%到-30%之间，成本收益分析表明意大利监狱人口低于最优水平。
We estimate the “incapacitation effect” on crime using variation in Italian prison population driven by eight collective pardons passed between 1962 and 1990. The prison releases are sudden (within one day), very large (up to 35 percent of the entire prison population), and happen nationwide. Exploiting this quasi-natural experiment we break the simultaneity of crime and prisoners and, in addition, use the national character of the pardons to separately identify incapacitation from changes in deterrence. The elasticity of total crime with respect to incapacitation is between −17 and −30 percent. A cost-benefit analysis suggests that Italy's prison population is below its optimal level.