Managing Differentiated Disintegration: Insights from Comparative Federalism on Post-Brexit EU-UK Relations

This article applies insights from comparative federalism to analyse different models for managing future EU–UK relations. The argument is that the stability of the EU–UK relationship before as well as after Brexit is best understood by examining the presence of federal safeguards. Drawing on Kelemen, four types of safeguards are identified as the means for balancing centrifugal and centripetal forces. During the United Kingdom’s European Union membership, the strong glue provided by structural and judicial safeguards was undone by the weakness of partisan and socio-cultural ones. However, each post-Brexit scenario is characterised by weaker structural and judicial safeguards. The most stable outcome is an indeterminate Brexit that limits the incentive to politicise sovereignty and identity concerns by ending free movement of people and reducing the saliency of European Union rules. Such stability is nevertheless relative in that, from a comparative perspective, federal-type safeguards were stronger when the United Kingdom was still in the European Union.