Modeling Ambitious Justice Reform: Prison Population Impacts of Shortening Long Sentences

• In Event: Extreme Sentences in America: Trends, Consequences, and Avenues for Reform

Abstract

To advance the policy conversation, decisionmakers and the public need to know the impact of potential policy changes. The Urban Institute has developed a prison population projection methodology using National Corrections Reporting Program (NCRP) data that can estimate how changes to admissions and time served for various offenses will impact state prison populations. In this paper, we investigate how the longest prison terms shape state prison populations, estimating the effect of reductions in time served for serious offenses. Our findings clearly point to the need to fundamentally rethink not just who goes to prison for low-level offenses, but also how long people stay in prison for violent crimes. This forecasting methodology paves the way for a more productive conversation about the need for tailored reforms that address the unique drivers of mass incarceration in each jurisdiction.

Authors

• Ryan King, Urban Institute

• Elizabeth Pelletier, Urban Institute

• Bryce Peterson, Urban Institute