Substance Use Disorder and Substance Use-Related Mortality in US Immigration Detention (2018-2025).

Abstract

To assess documented substance use indicators and the probable role of substance use disorders (SUDs) in deaths occurring in US Immigration and Customs Enforcement (ICE) custody between April 2018 and May 2025. A retrospective cross-sectional review was conducted using all 69 publicly available ICE Detainee Death Reviews (DDRs) during the study period. Medically licensed reviewers analyzed each DDR for documented substance use indicators, clinical screening or diagnosis, referral, treatment, and emergency response. Additional variables included demographic information, psychiatric symptoms, and access to medical or mental health care. Among 27 deaths involving a probable substance use history or related medical/psychiatric conditions, none showed documentation of SUD diagnosis, referral, or evidence-based treatment. Nine individuals (33.3%) died from complications potentially related to untreated substance use, including opioid and alcohol withdrawal. Over half of these cases showed documented signs of delayed emergency response. Although DDRs frequently noted patient "refusal" of care (n=11), none documented formal assessments of decision-making capacity. Most individuals in the sample had resided in the United States for over 2 decades before ICE detention. Our findings reveal probable gaps in the documented identification and treatment of SUD among individuals who died in ICE custody. Standardized behavioral health protocols, timely emergency response, and greater transparency are needed to address substance-related risks in immigration detention settings.