Will European Union Law Survive in the United Kingdom After Brexit?
The United Kingdom’s formal withdrawal from the European Union marked a historic constitutional shift. While the UK ceased to be an EU member state as of 31 January 2020, the legal consequences of this departure extend far beyond symbolic milestones. The central question is not only whether EU law will continue to influence the UK legal system, but how legal continuity and coherence will be maintained as the UK redefines its legal identity.
In the immediate aftermath of Brexit, both sides recognised the risk of legal disruption. A sudden disappearance of EU law — which had governed a vast array of commercial, regulatory and rights-based domains in the UK for nearly half a century — threatened to create legislative and interpretive voids that would undermine legal certainty.
Retained EU Law: A Bridge Between Systems
To address this challenge, the UK Parliament passed the European Union (Withdrawal) Act 2018. This legislation preserved a large body of EU law within the UK’s domestic legal framework after exit. Known as retained EU law, this body includes previously applicable EU regulations and directives that had been transposed into UK law before the end of the transition period, which ran until 31 December 2020. Like a legal snapshot, this transitional retention ensured that substantive rights and obligations did not simply vanish overnight.
The purpose of this approach was both pragmatic and constitutional: it provided continuity for businesses, citizens and courts while enabling the UK to gradually reshape its legal landscape from within. Retained EU law thus acted as a temporal bridge, preventing immediate legal vacuum and offering a stable foundation for future reform.
Judicial Interpretation and the Role of EU Jurisprudence
During the transition period, the European Court of Justice (ECJ) continued to influence legal outcomes in the UK much as it had before Brexit. After the transition ended, direct jurisdiction of the ECJ in UK courts ceased. However, historical ECJ case law remains an influential source for interpreting retained EU law, unless and until UK courts decide to depart from it. This provides a measure of interpretive consistency in applying legal norms that were established under EU membership.
The UK Supreme Court and other domestic tribunals are not strictly bound by past ECJ decisions in perpetuity, but they may give weight to them where appropriate, especially when retained EU law mirrors principles previously upheld by the Court of Justice. The evolution of domestic jurisprudence will shape how far this inherited body of law continues to resemble its EU origins.
Reform, Revocation and Legislative Autonomy
Retained EU law is not immutable. The UK Parliament and devolved legislatures retain full authority to amend, repeal or replace these legislative provisions as they see fit. This reflects the sovereign intent behind Brexit: to regain legislative autonomy and permit domestic policy to diverge from the EU’s legal framework where politically and economically desirable.
This has already begun to occur in some areas, with initiatives to reform or sunset aspects of retained law that were seen as outdated, duplicative or inconsistent with domestic priorities. While this process aims to tailor the legal landscape to UK needs, it also raises questions about legal certainty and alignment with international partners.
Institutional and International Implications
Even as the UK asserts legal autonomy, its economic and regulatory ties with the EU — and with other jurisdictions — continue to matter. Trade agreements, regulatory cooperation and mutual recognition regimes all require negotiation and adjustment. A key challenge for the profession, and for legal institutions more broadly, is to manage the interplay between domestic legal evolution and international legal obligations.
For lawyers advising clients — whether on cross-border commerce, regulatory compliance or human rights — understanding both retained EU law and its ongoing reform remains essential. This dual perspective is central to navigating a legal environment shaped by historical integration and contemporary sovereignty.
Conclusion: Between Continuity and Change
Will EU law survive in the UK after Brexit? The answer depends on how we define survival. Direct application of EU law — and ECJ jurisdiction — has ceased, affirming the UK’s legal independence. However, a substantial portion of EU-derived law lives on within the UK legal order as retained law, influencing rights, obligations and judicial reasoning. This retained framework offers continuity while providing space for deliberate reform.
At DelCanto, we view this moment as a pivotal phase in the evolution of UK law — one that demands rigorous legal analysis, strategic foresight and deep engagement with both domestic and comparative legal principles. The ability of lawyers and institutions to interpret, adapt and innovate in this context will shape the profession’s relevance in a post-Brexit legal landscape.