Abstract: Pregnant and postpartum women who are Black and use drugs are fighting to survive at the inter- section of 3 of the gravest public health crises of the 21st century US: (1) the maternal mortality epidemic; (2) an evolving overdose epidemic; and (3) intersectional discrimination. In a nation with the highest maternal mor- tality rate of all high-income countries, US Black women suffer mortality rates threefold higher than White women. Dire as this inequity is, a recent epidemiologic transformation of the US overdose epidemic is poised to widen it. While overdose mortality rates were markedly higher among White people for most of the 2000s, overdoses among Black people have surged recently, and since 2018 Black/White inequities have emerged. State legislatures have been actively responding to this crisis: 44 states have enacted >1 law governing drug use in pregnancy. Some laws are punitive, and seek to deter prenatal drug use through criminal sanctions (e.g., classifying drug use in pregnancy as child abuse/neglect). Others seek to expand substance use disorder (SUD) treatment for pregnant women (e.g., require that treatment programs prioritize pregnant women). Unfortunately, we know remarkably little about how these ubiquitous laws shape overdose or related health service use among Black pregnant/postpartum women who use drugs. In part, this silence reflects intersec- tional discrimination in medicine/public health: the field of maternal health has largely ignored people with be- havioral health conditions, and harm reduction has neglected pregnant/postpartum women, particularly Black women. The scant evidence that does exist is, however, alarming. The handful of studies on punitive laws largely confirm ACOG, CDC, and SAMHSA warnings that these laws undermine Black women’s health and healthcare use. The few studies of laws seeking to increase SUD treatment opportunities for pregnant women find that they have no effects or may actually reduce SUD treatment use among Black pregnant women. Guided by two Community Accountability Boards, the proposed study applies a mixed-methods sequential explanatory “QUAN qual” design to inaugurate a line of high-impact research and action into the possible ef- fects of select laws governing drug use in pregnancy on overdoses, SUD treatment use, and prenatal/ postna- tal care use among Black pregnant/postpartum women. Aims 1-3 are national in scope, and analyze multiple administrative databases to trace, for the first time, the pathways through which these 3 laws might shape Black pregnant/ postpartum women’s overdose risk and health service use. Aim 4 will explain and enrich Aim 1-3 findings through an in-depth qualitative case study of these pathways in one Metro Area (Atlanta). Aim 5 applies evidence-based community organizing methods to support community mobilization in Atlanta around select intervention targets identified in Aims 1-4. The proposed project will have high impact: it will help Black p...