Incarceration and Incapacitation: Evidence from the 2006 Italian Collective Pardon
利用2006年意大利集体赦免释放三分之一囚犯的自然实验，通过三种方法估计监禁对犯罪的剥夺能力效应，发现监禁的犯罪预防效果随监禁率上升而递减。
In August 2006, the Italian government released one-third of the nation's prison inmates via a national collective pardon. We test for a discontinuous break in national crime rates corresponding to the mass release. We also test for the effect of the return of the incarceration rate to its predicted steady state level on national crime rates. Finally, we exploit regional variation in prison releases based on the province of residence of pardoned inmates. All three sources of variation yield substantial incapacitation effect estimates and suggest that the crime-preventing effects of incarceration diminish with increases in the incarceration rate.