The end of exceptionalism and a strengthening of coherence? Law and legal integration in the European Union post-Brexit

The EU’s legal system has been built on the principle of a ‘single legal order’. Undeniably, however, differentiation has crept in. The UK has been at the forefront of seeking opt-outs and exceptions to the euro, Schengen etc. After Brexit, will others’ requests for special treatment continue, or will the Brexit experience strengthen the legal order? Is the EU’s legal system capable of absorbing differentiation in its fabric? This contribution argues that differentiation can only be accommodated so far in the Treaty arrangements without a wholescale re-evaluation of the purpose of EU law. The UK’s departure removes the Member State most ready to challenge some of the fundamentals of the legal order, but the article urges caution against a full re-characterisation post-Brexit. Instead, the article foresees a continuation of the status quo, in which differentiation exists in various forms but as exceptions to the rule, rather than the rule itself.