PROJECT SUMMARY Data consistently demonstrate alarming racial disparities among youth and adults impacted by the legal system, and multiple studies have documented that justice-impacted youth have substantially higher rates of psychiatric needs, substance use and HIV/STI risk behaviors than youth who have not had juvenile legal system contact. However, research elucidating the impact of structural, cultural and individual racism on the health and legal outcomes and disparities of justice-impacted ethnoracial minoritized youth and families is nascent. This study will advance the science in structural racism and discrimination (SRD) and its influence on public health and legal inequities by leveraging an existing statewide longitudinal dataset from Project EPICC as well as following up with 300 previously enrolled youth and caregivers (N=300 dyads or 600 participants total) to conduct once annual follow-up assessments and life course interviews. Informed by Ecodevelopmental Theory, Project EPICC followed 401 youth and an involved caregiver (55% ethnoracial minoritized youth) for two years starting from the time of first ever youth contact with the juvenile legal system. Data are available on the longitudinal trajectories of substance use, psychiatric symptoms, HIV/STI risk behaviors and recidivism and the multiple contributing risk and protective influences (individual, family and extrafamilial) on youth trajectories. Project EPICC-2 will expand the Ecodevelopmental Framework to study the longitudinal impact of structural racism and discrimination on trajectories of ethnoracial minoritized youth’s substance use, psychiatric, sexual and reproductive health and legal outcomes during adolescence and into young adulthood. Using statewide administrative data, we will expand original primary outcomes to include substance use and psychiatric services utilization to understanding more about direct influence of structural racism and discrimination on justice-impacted young adult healthcare services access and equity. Annual life course interviews with a stratified random subsample of 50 young adults and 50 caregivers will provide a more nuanced qualitative and contextual understanding of the impact of structural racism on adolescent, young adult and family experiences and trajectories. EPICC-2 will leverage an existing longitudinal dataset, pre-existing relationships with a large sample of justice-impacted families, an ecodevelopmental and intersectional (race, ethnicity, sex, gender, socioeconomic status) framework, an intergenerational approach and an accomplished multidisciplinary study team to answer critically important questions in the field of adolescent and young adult health disparities.