Data Analysis Incarceration Trends Jail Populations January 17, 2024
Turning Local Data into Meaningful Reforms
Effective criminal legal reform requires a strong understanding of the key challenges jurisdictions face in building safe and equitable legal systems, as well as an equally strong understanding of the carefully designed solutions—and how to thoughtfully implement them. Data and information must play critical roles in supporting each stage of legal system reform. With this in mind, the John D. and Catherine T. MacArthur Foundation launched the Safety and Justice Challenge (SJC), a major initiative to support local criminal legal systems in reducing over-reliance on jails as a response to social problems. Today, the SJC supports a national network of 57 cities, counties, and states in implementing a range of policy and programmatic interventions to re- shape local justice systems, with the aim of safely reducing the number of people who go to jail and how long they stay. Data, measurement, and evaluation has played a pivotal role in guiding this initiative—for identifying drivers of the jail popu- lation, designing innovative decarceration strate- gies, monitoring progress, and evaluating and understanding performance. The Institute of State & Local Governance at the City University of New York (CUNY ISLG) plays a leading role in these data collection and analysis activities across the SJC, serving as a central liaison between local jurisdictions, external researchers, technical assis- tance providers, and the MacArthur Foundation. Safety and Justice Challenge cities and counties lowered jail populations by 18.6 percent—or 11,010 individuals on average—since the start of the initiative. This data is made possible by the data collection efforts detailed in the Main Report.