Peer-led court navigation for people who use drugs passing through courthouses: a hybrid type 1 cluster randomized controlled trial study protocol

Background: Courthouses bring together people at multiple stages of criminal legal system involvement, including many with substance use disorders and elevated overdose risk. Yet outside of specialty courts, courthouses remain underused as settings for voluntary connections to treatment and related services. Peer-led court navigation may offer low-threshold linkage, but evidence of its effectiveness and implementation is limited. The Preventing Overdose and Promoting Recovery Through Court Navigation (POPCORN) study evaluates CourtConnect, a manualized peer-led court navigation intervention.Methods: POPCORN is an effectiveness-implementation hybrid type 1 study conducted in two Indiana county courthouses. An Engagement Council and 30 formative interviews informed development of CourtConnect. In the pragmatic cluster randomized controlled trial, courthouse enrollment clusters of shifts are randomized to CourtConnect or an information-only condition, with 600 participants enrolled across the two sites. CourtConnect provides peer-led navigation for up to three months, while comparison participants receive a community resource guide without navigation or follow-up. The primary outcome is administratively documented substance use disorder treatment engagement within 90 days. Secondary outcomes are fatal or nonfatal overdose and incarceration within 12 months. Outcomes are measured through linked statewide administrative records. The implementation evaluation uses process, fidelity, and adaptation measures and qualitative interviews guided by the Consolidated Framework for Implementation Research.Discussion: POPCORN will provide rigorous evidence about whether voluntary peer-led court navigation improves treatment engagement and affects overdose and incarceration under routine courthouse conditions. The implementation findings will identify what supports or impedes delivery of the intervention and inform courts and community partners considering similar models.Trial Registration: The trial is registered at ClinicalTrials.gov (NCT07700407).