American Federalism and Health Policy Spillovers: Insights from the Opioid Crisis

Abstract This article examines how federalism shapes US public health crisis responses, emphasizing that policy divergence across states creates negative spillovers that undermine effectiveness. It develops a framework arguing that policy congruence among neighboring states is key to health outcomes. Applying this to opioid mortality (2009–2016), the study finds that states aligning regulations—such as Prescription Drug Monitoring Programs—experience fewer cross-border opioid flows and lower mortality. By focusing on horizontal policy diffusion rather than federal mandates, this research shows how federalism can enhance coordination under certain conditions. These findings refine our understanding of state sovereignty, policy diffusion, and health outcomes, suggesting that shared policies help mitigate the pitfalls of fragmented governance.