The politics of pain: Medicaid expansion, the ACA and the opioid epidemic

Federalism allows state politicians opportunities to undermine or support for federal policies. As a result, voters often have varied impressions of the same federal programmes. To test how this dynamic affects voting behaviour, I gather data on the severity of the opioid epidemic from 2006–2016. I exploit discontinuities between states that expanded Medicaid and those that did not to gain causal leverage over whether expansion affected the severity of the epidemic and whether these policy effects affected policy feedback. I show that the decision to expand Medicaid reduced the severity of the opioid epidemic. I also show that expanding Medicaid and subsequent reductions in the severity of the opioid epidemic increased support for the Democratic Party. The results imply that the Republican Party performed better in places where voters did not have access to Medicaid expansion and where the epidemic worsened, demonstrating an unintended consequence of federalism on policy feedback.