By The Justice Policy Institute

Despite the limited evidence base for its effectiveness and the significant burden it imposes on those under supervision, jurisdictions across the United States have expanded the use of electronic monitoring (EM) – technology that tracks and sometimes restricts a person’s movements – to supervise justicesystem-involved people released to the community. EM presents an appealing alternative to judges and prosecutors who want to limit jail or prison use but seek additional security to ensure public safety. This is true in Maryland, where the use of EM to supervise pretrial clients has grown significantly over the past decade and increased sharply following the onset of the COVID-19 pandemic, due in part to a one-time federal allocation of resources to fund supervision by private providers. However, despite this increase, there is very little information about the use of EM to supervise people awaiting trial in Maryland. We have no idea how many people have been monitored by the technology, its impact on their lives, or how effective it is with various populations. To inform these decisions, the Justice Policy Institute conducted a study on the use of EM to supervise pretrial clients in Maryland. This report explores the day-to-day realities of electronic monitoring, its effects on individuals under supervision, and offers recommendations to enhance service delivery based on proven best practices. Research on the efficacy of pretrial EM suggests that: • EM Does Not Reliably Reduce Failure to Appear (FTA) or Recidivism in Pretrial Populations. Although the use of EM has skyrocketed across the country, there is no clear and convincing evidence that EM effectively reduces FTA rates or recidivism for pretrial supervisees. This contrasts with other strategies like court notification and reminder systems, which have much stronger evidence of efficacy in reducing FTA rates. • Best Practices in Pretrial Release, Supervision, and EM Are Grounded in Validated Risk and Needs Assessment. The central elements that comprise an evidence-based approach to pretrial justice involve: • Expanding citation and diversion options; • Implementing a legal framework with a presumption of least restrictive release; • Ensuring due process in all hearings; • Grounding all decision-making in the use of a validated pretrial risk and needs assessment instrument (PRAI); and • Strictly limiting the use of pretrial detention and other restrictive measures, including electronic monitoring, to instances where an individual is at high risk of failing to appear or reoffending. EM Imposes a Significant Burden That Must Be Considered in Policy and Practice Decisions. EM surveillance presents serious challenges for individuals and severely limits their freedom. If EM is assigned to those at low risk of FTA or recidivism and drives net-widening in the corrections system, it is likely to cause unnecessary harm. However, when implemented and monitored effectively and humanely, it can be a useful strategy when used as a true alternative to jail and to increase the number of people released to their homes. 

Baltimore, MD: The Abell Foundation, 2025. 48p.