From capacity to sovereignty: Legislative politics and differentiated integration in the European Union

The literature suggests that legislative politics among European Union Member States is characterised by economic exchanges, and constrained by the social norms of a European community of legislators. Both views draw a clear line between the legislative process and the conflicts over sovereignty that have left their mark on treaty making and European public opinion since the 1990s. This article suggests revisiting this view, based on an analysis of why Member States have opted out of legislation from the 1970s to today. It argues that differentiation, while once a response to capacity problems of relatively poor countries, has recently become driven by sovereignty concerns of the Union's wealthy and nationally oriented Members that oppose the EU's intrusion into core state powers. The article presents evidence for the impact on legislative outcomes of factors so far thought not to matter. The results indicate greater European‐level legislative responsiveness towards national sovereignty demands than previously recognised. They underline that the nature of European politics has been changing with the EU's push into core state powers.