County Immigration Enforcement in the Context of Unsettled Federalism: From Obama to Trump

We examine patterns of county participation in immigration enforcement across the Obama and Trump administrations and responses to the Trump administration’s efforts to mandate local compliance with Immigration and Customs Enforcement (ICE) directives. We focus on the policy that directly speaks to local discretion in enforcing federal law—namely, the willingness of local officials to render immigrant detainees to ICE. We find that underlying patterns of detainee transfers from counties to ICE were largely consistent between the Obama and Trump administrations. Nonetheless, the rate of detainee transfers increased during the Trump administration, an outcome associated with county support for Trump in the 2016 election. The findings suggest that partisanship is an entrenched source of diverging county enforcement practices, increasing intergovernmental conflict and undermining the “steam valve” potential of immigration federalism.