Research Shows that Unnecessary Pretrial Detention Harms People in Many Ways

The vast majority of the 750,000 people who are in our nation’s jails on any given day are awaiting trial and presumed innocent. Many of them are charged with low-level, nonviolent crimes, but are unable to afford money bail. Taxpayers spend $14 billion on pretrial incarceration each year—and that does not take into account the human costs. Even a short time in pretrial detention can cause someone to lose his or her job, housing, health care, and child custody.

A number of research studies have documented the harmful effects of pretrial detention on individuals, families, and communities. For example, people who are detained before trial are more likely to be convicted, more likely to be sentenced to incarceration, and receive longer sentences than people who were not detained. A study conducted in Philadelphia showed that pretrial detention increases the chances of conviction by 13 percent, increases fees owed by 41 percent, and increases sentence lengths by 42 percent.

A separate study using data from Harris County (Houston) found that pretrial detention made it 25 percent more likely that people would plead guilty, 43 percent more likely they would be sentenced to jail; and people held in custody before trial received sentences of more than double the length of those who were not held in custody.

Pretrial custody also worsens outcomes after people complete their sentences and reenter their communities. Research shows that being held before trial increases recidivism and hurts people’s chances to obtain employment.

Pretrial detention disproportionately impacts people of color, according to the research. For example, a study in Miami and Philadelphia indicated that judges relied on inaccurate stereotypes about black defendants that exaggerated the relative danger of releasing them.

A growing number of states and counties have adopted pretrial reforms to make their systems fairer and more effective. These reforms include expanding the release options following or in lieu of arrest, amending the pretrial legal framework to clarify who is eligible for pretrial detention and providing for preventive detention, and adopting the use of pretrial risk assessments to inform the release decision.

In 2011, when the Laura and John Arnold Foundation entered the criminal justice field, the foundation wanted to know what new research could support a widespread policy change. Although pretrial risk assessments had been studied and validated for more than 60 years, larger-scale adoption of assessments had not occurred. The foundation learned that most existing assessments required extensive staff resources, many were jurisdiction-specific, and none predicted the risk of pretrial violent activity. In 2013, in partnership with leading researchers, the foundation set out to test the feasibility of a fair, user-friendly assessment that could be used across jurisdictions and would use only administrative data.

Criminal justice researchers designed the PSA using the largest, most diverse set of pretrial records ever assembled—750,000 cases from nearly 300 jurisdictions across the country. Since its development, researchers have validated the PSA using more than 650,000 cases from diverse jurisdictions in the Northeast, Midwest, West, and two states. Research projects currently underway include studies to measure jail populations, release rates, pretrial recidivism, and court appearances before and after PSA implementation; validation studies to test for predictive accuracy and predictive bias; and qualitative studies to assess stakeholder perception and use.

In 2018, LJAF issued a Request for Proposals (RFP) “To Conduct Research on the Public Safety Assessment, Risk Assessments, and Pretrial Detention.” The RFP outlines a robust research agenda that includes the rigorous evaluation of PSA performance, the PSA factors and the manner in which those factors are used to calculate PSA scores, judicial decision making, and system impact, as well as exploratory research projects on new pretrial risk assessment models and the impact of pretrial detention.