Abstract: | Environmental regulation is frequently implemented through asystem that allows states to choose whether to assume primaryauthority, or "primacy," for implementation and enforcement.This study looks at what causes states to assume this authorityin two important areas of environmental policy: air and waterpollution. It finds that in each policy area, primacy assumptionis unrelated to the "greenness" of state environmental policygenerally and negatively related to indicators of policy innovationwithin that area. Rather than being driven by commitment tothe environment, primacy assumption appears to be driven predominatelyby other factors, which differ substantially across the airand water policy arenas. These findings call into question thewidely held view that primacy assumption is an indicator ofstate environmentalism and indicate that a more nuanced viewof what causes states to assume primacy is necessary to fullyunderstand the dynamics of intergovernmental policy implementation. |