Abstract

How does a shift in political leadership impact policy compliance in a polarized society? Leveraging the differences in Medicaid expansion (via the Affordable Care Act) across state borders, we examine the changes in the uninsured rate across policy borders under the Trump administration. We find that Republican counties on the expanded side experience a surprising increase in the uninsured rate relative to Republican counties on the unexpanded side, reversing the policy progress made during the Obama era. The rising discontinuity in the uninsured rate is associated with health costs, with Republican counties on the expanded side also seeing a relative rise in opioid use and overdose mortality. No such discontinuity is found among Democratic counties across the policy border. I find no evidence that the reverse effects are driven by pre-trends, migration across state borders, known state policy changes, or within-state variation in funding. I present elite cues and information gaps as the mechanisms. The reverse effect is more pronounced in counties with higher ACA repeal intensity from local political elites and less so in counties with higher health insurance advertising intensity from insurance companies.

Keywords: Presidential Election; ACA; Medicaid Expansion; Policy compliance.