Does sentence length affect the risk for criminal recidivism? A quasi-experimental study of three policy reforms in Sweden

Objectives This study examines the relationship between incarceration time and post-release recidivism among first-time incarcerated adult offenders. Methods A quasi-experimental design was adopted consisting of three policy reforms that were treated as separate natural experiments. While holding imposed sentence length constant, these policy reforms either decreased or increased the required share of a sentence inmates needed to be incarcerated before being eligible for parole. Data consisted of large-scale administrative records containing all convictions for the Swedish cohorts born in 1958 and later. Results Results indicate that neither increased nor decreased incarceration time had a statistically significant effect on post-release recidivism, irrespective of how recidivism was measured. Conclusions Findings reveal little evidence for incarceration time having a criminogenic or specific preventive effect on post-release recidivism.