Courting Controversy? The Constitutional Implications of the Court of Justice of the European Union’s Involvement in the Resolution of Disputes After Brexit

The article sheds light on the under-discussed, but nonetheless constitutionally significant issue of the changing landscape for dispute resolution between the United Kingdom (UK) and the European Union (EU) post-Brexit. This pertains, in particular, to the Court of Justice of the European Union’s (CJEU) likely involvement in the resolution of disputes between the two parties across the arrangements governing both the UK’s withdrawal from, and future relationship with, the EU. The authors explore the dispute resolution mechanisms under the Withdrawal Agreement and the Trade and Cooperation Agreement (TCA), as well as the Court’s ‘legacy role’ in relation to (former) EU law concepts beyond the confines of the two Agreements. This article thereby evaluates the constitutional importance of the future role of the CJEU as a dispute settlement forum in these contexts, including the relationship between sources of ‘norms’, and the extent to which the UK will remain subject to its jurisdiction, or at least its influence, in the long term, whether directly or indirectly. It is argued that the CJEU’s influence, as well as the influence of EU law in the UK more generally, is now mediated through domestic law concepts such as the recently devised concept of ‘assimilated EU law’, which replaces ‘retained EU law’, and which have the capacity to obfuscate the constitutional origins, and thereby constitutional legacy, of EU-derived concepts. The article further contends that the ostensibly restricted involvement of the CJEU in the UK-EU relationship after Brexit must be appraised through the prism of the Withdrawal Agreement and TCAs’ provisions, which possess uniform legal force in both jurisdictions. The Agreements indicate a more expansive and enduring constitutional role for the CJEU and EU law concepts broadly speaking, than the one the UK Government has publicly conceived. Consequently, a notable dissonance emerges between the political objective of ‘taking back control’, and the reality created by the legal framework governing the UK’s cooperation with the EU, including the mechanism for resolving future disputes. Despite Brexit, the CJEU will continue to shape the constitutional contours of the relationship between domestic and Union law, as well as between domestic sources of law, for many years to come.