State Preemption of Local Authority: Explaining Patterns of State Adoption of Preemption Measures

State preemption of local policymaking has attracted increasing attention from scholars, public officials, and citizens, as states have prevented local governments from boosting the minimum wage, regulating firearms, and barring certain forms of discrimination, among other policies. Although scholars have examined the legal dimensions of state preemption and analyzed preemption in specific areas, we lack a comprehensive account of which states have adopted preemption laws and why some states are more active than others in adopting them. Using a dataset drawing on preemption legislation in seventeen policy areas, we test support for competing explanations for variation in adoption of state preemption measures. Our general conclusion is that political factors are more significant than institutional features in explaining state preemption activity. More specifically, and consistent with expectations, we find preemption measures are more likely to be adopted by Republican-controlled states. We also find that legislative professionalism, political culture, and home-rule status are correlated with the prevalence of preemption measures.