Giovanni Mastrobuoni (Collegio Carlo Alberto)

“Open or Close the Door? Prison Conditions and Recidivism”

Abstract
The question of how prison conditions affect recidivism is very important. In designing a prison system, one would want to know the answer. We estimate the effect on recidivism of replacing time served in a common closed-cell prison with time served in an open-cell one, mimicking an experiment where the time spent in the two prison regimes is randomly assigned. We deal with the endogenous assignment of inmates to different prison regimes using variation that is driven by nearby prisons’ overcrowding. Switching regimes for a year, which represents 60 percent of the average sentence, reduces recidivism by around 6 percentage points, or 15 percent; a large effect compared to most other interventions aimed at reducing recidivism. The effects are largest for inmates with very low levels of education and are weak for hardened criminals. More than a single mechanism underlies these effects.