The contingent diffusion of Parliamentary oversight institutions in the European Union

Abstract

What explains the variation in institutional adaptation of national parliaments to European integration? Whereas the existing literature has mainly focused on domestic conditions, we explain institutional adaptation to integration by focusing on inter-parliamentary diffusion. Our argument draws on “learning” mechanisms of diffusion on the demand side and on “emulation” mechanisms on the supply side. We relate parliamentary demand for external inspiration to uncertainty about functional oversight institutions, and the selection of sources to perceptions of similarity and success. Demand arises in new European Union member parliaments and young democracies that then turn towards culturally alike countries and old democracies. Using spatial econometrics, we demonstrate support for our argument while ruling out alternative diffusion mechanisms such as spatial proximity and learning from Scandinavian frontrunners once we control for links along cultural similarity and democratic experience. The results underline the limits of the ‘isolated polity’ approach in the comparative study of institutions in Europe’s closely integrated political system, while also showing that, even in this favorable environment, diffusion pathways are contingent on the mechanisms generating demand among policy-maker and shaping their selection of sources for external information.