When politics meets policy: a realist review of how political context shapes the impact of public health legal interventions

BackgroundPublic health laws—whether focusing on taxation, bans, mandates, or licensing—are powerful tools for reducing risk behaviors and improving population health. However, identical legal interventions often produce starkly different outcomes across jurisdictions. Political and social contexts are increasingly recognized as key determinants of such variability.ObjectiveThis study aimed to examine how and why public health legal interventions succeed or fail under different political circumstances, drawing on a Realist Review approach. We synthesized the interplay between legal epidemiology and political determinants of health to develop a deeper understanding of the mechanisms driving health policy outcomes.MethodsWe followed RAMESES guidelines to identify and analyze 20 empirical studies, policy analyses, and global reports published from 2000 to 2023. We included sources that explicitly addressed both public health law or policy interventions and the political environment (e.g., trust in government, partisanship, lobbying, global donor influence). Using a Context–Mechanism–Outcome (CMO) framework, we coded and synthesized patterns to refine our initial program theory on how