9. The European Union and Brexit

This chapter focuses on the constitutional implications of the UK’s membership of the European Union and the constitutional implications of its exit from the EU (or ‘Brexit’). The chapter examines how EU law was accommodated within the UK legal system during the period of the UK’s membership of the EU, and in particular considers the consequences of the primacy of EU law for the doctrine of parliamentary sovereignty. The chapter also considers the extent to which lessons learned about the UK constitution as a result of EU membership will remain relevant now that the UK has left the EU.