"The study by the [Pennsylvania Sentencing] Commission found that neither length of sentence nor the imposition of a mandatory minimum sentence alone was related to recidivism. In the four recidivism studies conducted as part of this project, the recidivism rates (i.e., arrest for a new crime or technical violation resulting in reincarceration) three years after release were as follows: drug delivery offenders (54%), school zone offenders (57%), repeat violent offenders (54%) and firearms offenders (50%). Younger offenders, those with a greater number of prior arrests and/or convictions, and those sentenced to prison were more likely to recidivate; those sentenced for a drug mandatory were more likely to be re-arrested for a drug offense and those sentenced for a repeat violent offense or firearms mandatory were more likely to be re-arrested for an offense against a person. Consistent with finding of other research on deterrence and recidivism, the certainty of incarceration may be more important than the duration of the confinement."


Pennsylvania Commission on Sentencing: Report to the House of Representatives, House Resolution 12, Session of 2007, "A Study on the Use and Impact of Mandatory Minimum Sentences," (Harrisburg, PA: October 2009), p. 3.