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.     

Deterrence and Incapacitation Effects in a Closed Area: A Case Study of Auto Theft in Taiwan

Deterrence and incapacitation effects of auto theft are estimated with a full consideration of substitution effects across crime types and across districts in a closed area in which none of the effects will leak out. It is found that the increase in the cleared rate of auto theft crime in a certain district and in other districts strongly deters the auto theft in that district, indicating that the across‐district deterrence effect dominates the across‐district substitution effect. The across‐crime deterrence effect significantly exceeds the across‐crime substitution effect for close crime (general theft), but is insignificant for distant crime (violence).