Public Safety Assessment Tool

During its first 15 months of implementation, just 6% of defendants released by the PSA were arraigned for a subsequent crime; 20% failed to appear in court.
















The PSA is an objective, research-based pre-trial risk-assessment tool, designed by the Laura and John Arnold Foundation (LJAF), that measures risk factors to assist judges in making release/detention determinations. The SF Pretrial Diversion Project (SFPDP) completes a PSA on every person booked into SF County Jail for a new felony or non-cited misdemeanor.

The PSA measures three types of risks during the pre-trial stage: the likelihood a defendant will commit a new crime, the likelihood a defendant will commit a new violent crime, and the likelihood a defendant will fail to return to court.

Predicting Risk

The PSA relies on specific characteristics that indicate a statistically significant increased risk of pretrial failure. By analyzing data from over 1.5 million cases drawn from more than 300 jurisdictions across the U.S., LJAF found the following risk factors are the strongest predictors of a defendant's likelihood to miss a subsequent court date and to reoffend:

  1. Whether the current offense is violent
  2. Whether the person has a pending charge at the time of arrest
  3. Whether the person has a prior misdemeanor conviction
  4. Whether the person has a prior felony conviction
  5. Whether the person has a prior conviction for a violent crime
  6. The person’s age at the time of arrest
  7. Whether the person failed to appear at a pretrial hearing
  8. Whether the person has previously been sentenced to incarceration

Risk Management

Based on three scores generated by the PSA—failure to appear (FTA), new criminal activity (NCA), and new violent criminal activity (NVCA)—the SF Pretrial Diversion Project applies a Decision Making Framework, resulting in recommendations that detain the highest risk defendants, release moderate risk defendants with interventions and services targeted to mitigate risk, and release low risk defendants with minimal or no conditions.