Does longer incarceration deter or incapacitate crime? Evidence from Truth-in-Sentencing reform

This article evaluates how Truth-in-Sentencing (TIS) laws impact both violent and property crimes through mandating violent offenders to serve a substantial proportion of sentenced terms before being eligible to release to community supervision. Focusing on states with effective TIS laws, I utilize the difference-in-differences design to investigate the treatment effect of TIS on crime. I observe statistically significant decline in both violent and property crimes in TIS states. A series of placebo tests confirm the robustness of the estimates and inferences. The dynamic impact of TIS is heterogeneous among the seven categories of violent and property crimes in TIS states: murder and robbery rates decline almost immediately after TIS, while property crime takes longer time to exhibit significant decline.