Independent, objective, nonpartisan research
Report · December 2019

Pretrial Risk Assessment in California

Heather Harris, Justin Goss, and Alexandria Gumbs

The policies governing California’s pretrial system are undergoing substantial change. Amid recent correctional reforms and ongoing challenges to the state’s bail system, pretrial risk assessment has emerged as a way to help counties make decisions about whether arrested individuals should remain in the community or be detained until any charges stemming from that arrest are resolved.

This report presents an overview of pretrial risk assessment in California and offers considerations for using, evaluating, and improving the effectiveness of local pretrial risk assessment systems.

  • Forty-nine of California’s 58 counties use pretrial risk assessment tools alongside bail. These tools rely on criminal history, demographic, and/or socioeconomic information to make “risk predictions” of whether individuals are likely to be arrested during the pretrial period or to miss their court date.
  • A risk assessment tool is only one component of informed pretrial decision making. A comprehensive pretrial policy framework also includes an explanation of why a particular tool was chosen and how it should be used-as well as guidance regarding how risk assessment results should translate into decisions about release with or without supervisory conditions, or detention, in individual cases.
  • Equity is an ongoing concern. Critics argue that risk assessment tools that use criminal history could propagate preexisting inequities in the criminal justice system for racial minorities and homeless, unemployed, and impoverished individuals. However, proponents maintain that these tools offer new opportunities for monitoring and evaluating accuracy-which could ultimately help mitigate inequities.
  • Counties may face data challenges in testing a tool’s accuracy and equity. Local testing is critical, in part because many tools were not developed with populations that include Latinos and Asian Americans. Since the criminal history data used in these tools may be housed in different agencies and many counties may not process enough cases to properly test their tool on their own, data-sharing agreements and cross-county collaboration may be necessary.
  • Transparent decision making is essential. By carefully tracking the risk predictions made by their assessment tool-as well as how these predictions are translated into release or detention decisions-counties can identify any patterns of inconsistency, inaccuracy, and inequity. To promote transparent decision making, judges and pretrial services officers should explicitly state their reasoning if they override the prescribed recommendation.

Developing a pretrial risk assessment system that balances an arrested individual’s right to liberty and the need to preserve victim and public safety, while also promoting equity, is an ongoing endeavor. With transparent decision making, as well as consistent and complete data collection, counties will be in a strong position to conduct the routine monitoring, testing, and evaluation necessary to identify areas of weakness and ensure their pretrial decisions align with local policy objectives.


Criminal Justice