What is the PSA?

Across the nation, judges, legislators, researchers, community leaders, and others are engaged in important conversations about how to improve pretrial decision making. A step forward in the science of risk assessment, the Public Safety Assessment uses neutral, reliable data to help judges make decisions that promote public safety and contribute to a fairer and more efficient criminal justice system.


Research shows that defendants who pose little threat to public safety but cannot afford to pay money bail often spend unnecessary time in jail awaiting trial, while defendants who do pose a threat to public safety are frequently released from pretrial detention. As the public demand for bail reform increases across the United States, a growing number of states, counties, and cities are looking for ways to improve the fairness of their pretrial release and detention decisions.

The Public Safety Assessment is a risk assessment that provides judges with reliable and neutral information about defendants during the pretrial phase. Judges use this data to inform their release decisions.

Learn more

Risk Factors and Formula

The PSA examines nine factors related to a person’s age, current charge, and criminal history and produces two risk scores: one that predicts risk of failure to appear for future court appearances, and a second that predicts risk of committing a new crime if released before trial. The scores are based on a one to six scale, with higher scores indicating a higher level of risk. The PSA also flags defendants who indicate an elevated risk of committing a new violent crime if they are released before trial. The PSA results can help inform a judge’s decision making; however, the final release decision always rests with the judge.

Learn more

The PSA In Context

The pretrial justice field is experiencing a landmark moment. Lawmakers around the country, encouraged by calls for reform from judges, prosecutors, public defenders, law enforcement, and advocacy groups, are enacting new policies and practices that address many of the ills of the current system. State legislatures are crafting legislation on the use of money bail, pretrial monitoring and supervision options, and speedy trial provisions. Police, prosecutors, and public defenders are asking tough questions about how lower-level crimes are charged and weighing potential alternatives. Advocacy groups are raising important questions regarding potential racial bias and racial disparities in the use of risk assessments. It is within this broader context that pretrial risk assessment can play an important role.

Opportunities to improve the system exist throughout the pretrial phase, which begins the moment an officer encounters someone he suspects may be violating the law and ends when an individual is either released with no charges or charged and the case reaches a disposition. Law enforcement, prosecutors, and judges make many decisions during this period, and each has a significant impact on the individual they are interacting with. As such, there are many opportunities for these stakeholders to use their discretion to release people.

Risk assessments such as the PSA are used to inform the release decision, when judges must weigh whether to release or detain someone who has been charged with an offense before trial. To improve the whole pretrial decision making process—from the first encounter to case disposition—jurisdictions can consider a broad set of pretrial reforms beyond the use of risk assessments. It is through system-wide reforms such as these, and broad local discussions about pretrial justice, that real change is achieved.

This website aims to connect communities involved in PSA implementation so they may learn from one another. In this way, we hope to improve understanding of pretrial risk assessment use by offering knowledge and guidance to a national audience.


The PSA was developed using the largest, most diverse set of pretrial records ever assembled—750,000 cases from nearly 300 jurisdictions across the United States. The researchers analyzed the data to determine which factors were most predictive of the likelihood a person will fail to appear at future court appearances, or will commit a new crime—or a new violent crime—while awaiting trial.

Since the first pilot sites in 2013 and 2014, the PSA has been adopted by more than three dozen cities, counties and states across the U.S. To date, researchers have tested and validated the PSA using more than 650,000 cases from implementing jurisdictions. And in May 2018, and the Laura and John Arnold Foundation announced plans for a robust research agenda to continue and expand this work.

Learn more

Implementing the PSA

The PSA implementation process is divided into six phases, some of which run concurrently. For most jurisdictions, the process takes six to eight months to complete. Instructional guides and supporting resources are available for each step of the implementation process.

Learn more

Technology Integration
Managing Risk
Measuring Risk