Learning Outcomes
This article explains the principal sources of retained EU law under the European Union (Withdrawal) Act 2018 and how they fit within the UK constitution after Brexit. It outlines the structure and operation of EU-derived domestic legislation, direct EU legislation and retained EU rights, highlighting their status in the domestic hierarchy and the continuing, modified principle of supremacy. It examines the interaction between retained EU law and primary and secondary legislation, focusing on how conflicts are resolved and when Parliament or ministers can amend, repeal or disapply retained provisions. It discusses the role of the courts in interpreting retained EU law, including reliance on retained EU case law, the circumstances in which higher courts may depart from CJEU authority, and the use of purposive interpretation and general principles. It explores how these rules apply in typical SQE1-style problem questions involving devolved competence, statutory interpretation, and challenges to government decision-making, enabling accurate identification of the relevant category of retained EU law, the applicable hierarchy rules and the appropriate litigation strategy.
SQE1 Syllabus
For SQE1, you are required to understand the sources of retained EU law and their operation within the UK constitution post-Brexit, with a focus on the following syllabus points:
- The nature and core sources of retained EU law in UK law post-Brexit
- The legal mechanisms by which EU law became part of UK law and their ongoing effects
- The European Union (Withdrawal) Act 2018—structure, purpose, and interpretation, including its key provisions (ss. 2, 3, 4 EUWA 2018)
- The differences between (and examples of) EU-derived domestic legislation, direct EU legislation, and retained EU rights
- The concept and operation of the supremacy of retained EU law over pre- and post-Brexit domestic statutes and delegated legislation
- The practical process and constitutional limits for amendment, repeal, and judicial interpretation of retained EU law
- The approach to and hierarchy of retained EU case law in the UK courts
- The effect of retained EU law on devolved legislatures and administrative bodies, and its relationship with the Withdrawal Agreement
- Statutory interpretation in light of retained EU law and the ongoing impact of EU general principles
Test Your Knowledge
Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.
- What are the three main sources of retained EU law under the European Union (Withdrawal) Act 2018?
- How does the principle of supremacy apply to retained EU law after Brexit?
- Which UK courts may depart from retained EU case law, and under what circumstances?
- What is the difference between EU-derived domestic legislation and direct EU legislation?
Introduction
Retained EU law forms a fundamental component of UK public law, ensuring legal stability in the wake of the UK's withdrawal from the European Union. It refers to the body of EU law which, by virtue of the European Union (Withdrawal) Act 2018 (EUWA 2018), was preserved and incorporated into UK law at the end of the transition period, thus avoiding gaps and uncertainty. Recognising the practical need for legal continuity, Parliament enacted detailed provisions which allowed for the retention, modification, and eventual repeal of EU rules and rights within domestic law.
This framework operates against a constitutional background where the doctrine of parliamentary sovereignty remains central, but is tempered by the specific rules carved out by withdrawal legislation, the ongoing effect of the supremacy of retained EU law in particular situations, and the need for consistent interpretation by the UK courts. Moreover, the division between types or sources of retained EU law shapes how they can be amended, interpreted, or repealed—an essential point for legal problem-solving and advice, especially in the context of constitutional and administrative law.
Key Term: retained EU law
The body of EU law preserved in UK law as it stood at 11:00 pm on 31 December 2020 (IP completion day), by the European Union (Withdrawal) Act 2018. It consists of certain types of EU and EU-related UK law in force immediately before IP completion day, now forming a category of UK law subject to amendment and interpretation by domestic institutions.
Sources of Retained EU Law
The European Union (Withdrawal) Act 2018 took a "snapshot" of EU law as it existed in UK law at IP completion day, converting relevant provisions into UK law. This conversion process established three main sources of retained EU law:
EU-derived Domestic Legislation
This source includes any UK legislation, whether primary Acts of Parliament or secondary legislation (statutory instruments), that was enacted to implement EU obligations and was in force immediately before IP completion day. This primarily covers laws passed to transpose EU directives—many of which required action by domestic legislators—but also includes domestic rules made to comply with EU regulations, decisions, or treaty provisions. Such instruments retain their original legal status: an Act passed to implement an EU directive remains primary legislation (unless repealed), while regulations made under the authority of the now-repealed European Communities Act 1972 (particularly section 2(2)) are preserved as secondary legislation, unless explicitly removed or amended.
These instruments typically span areas such as employment law, environmental regulation, consumer protection, and financial services, among others, and continue to function as part of the UK's legal system, subject to amendment or repeal by future legislation.
Key Term: EU-derived domestic legislation
UK primary or secondary legislation made to implement the UK's EU obligations—especially EU directives—and preserved as retained EU law after Brexit, holding its status as either primary or secondary legislation.
Direct EU Legislation
Direct EU legislation means EU legal instruments—predominantly regulations, but also certain decisions and tertiary acts—which were directly applicable in all member states (including the UK). Unlike directives, these did not require implementing domestic legislation to become binding; rather, they automatically took effect and created enforceable rights and obligations in UK law.
On IP completion day, the text of these instruments as in force was incorporated into UK law by virtue of s.3 EUWA 2018. In practice, this category covers a wide range of technical regulatory rules, from air passenger compensation (under Regulation 261/2004) to product safety, banking, and competition law.
For operational purposes, direct EU legislation is divided into two sub-types: principal retained EU legislation (mainly regulations and certain other substantial instruments) and minor retained EU legislation (mostly tertiary acts and certain decisions), each with implications for how and by whom they can be amended (see below).
Key Term: direct EU legislation
EU regulations, certain decisions, and tertiary legislation that applied directly in the UK without domestic implementation and, after Brexit, are retained as part of UK law, in the form they had at IP completion day.
Other Retained EU Rights
Section 4 EUWA 2018 (see Key Term: s.4 EUWA 2018) captures rights, powers, obligations, restrictions, remedies, and procedures that had effect in UK law by virtue of s.2(1) of the European Communities Act 1972, and were recognised by a court or tribunal before IP completion day. This category most notably encompasses directly effective treaty articles (for example, directly effective rights under Article 157 TFEU concerning equal pay) and certain rights from directives and decisions, provided they had been declared directly effective by the courts prior to Brexit.
Key Term: retained EU rights
Rights, powers, liabilities, obligations, and remedies arising under EU Treaties or provisions directly effective in the UK and recognised as such by a court or tribunal before IP completion day, and preserved under s.4 EUWA 2018.Key Term: s.2 EUWA 2018
Provision preserving all domestic enactments (other than those excepted) made under section 2(2) of the ECA 1972 or otherwise for the purpose of implementing EU law, if in force immediately before IP completion day.Key Term: s.3 EUWA 2018
Provision by which direct EU legislation (regulations, certain decisions and tertiary acts) which was operative in UK law immediately before IP completion day is incorporated as part of domestic law.Key Term: s.4 EUWA 2018
Provision by which directly effective rights, powers, liabilities, obligations, restrictions, remedies, or procedures available in the UK before IP completion day (by virtue of s.2(1) ECA 1972) are retained in UK law—provided they have been recognised by a court or tribunal before that date.
Worked Example 1.1
A statutory instrument implementing an EU directive regulating working conditions in the UK was made under section 2(2) ECA 1972 and in force at IP completion day. Does it still apply after Brexit?
Answer:
Yes. Under s.2 EUWA 2018, this is retained as EU-derived domestic legislation and continues in force unless specifically amended or repealed by subsequent UK legislation.
Differences Among the Sources
A key practical distinction between these categories is how they can be amended post-Brexit: EU-derived domestic legislation continues to have its original status (as primary or secondary legislation), and so can only be amended by an instrument of an equivalent (or superior) level. Direct EU legislation is, for most purposes, treated like primary legislation and can only be amended by an Act of Parliament or in some cases by delegated legislation as permitted by the Withdrawal Act or new statutes.
Other (Excluded) Categories
Not all forms of EU law are retained. Notably, the Charter of Fundamental Rights of the European Union is not retained by the Withdrawal Act, and certain directly effective Treaty provisions relating to the single market, customs union, and freedom of movement were not carried forward into UK law after IP completion day due to the policy choices made as part of the Brexit process.
The Principle of Supremacy and Retained EU Law
Previously, the doctrine of the supremacy of EU law established by the Court of Justice of the European Union meant that EU law took precedence over any conflicting domestic law, including Acts of Parliament, enacted both before and after the European Communities Act 1972. As a result, the courts would disapply national law where it conflicted with enforceable EU provisions.
Following Brexit, this principle is altered by the EUWA 2018:
- Retained EU law retains a constrained form of "supremacy" over UK legislation that was passed or made before IP completion day. If there is a conflict between retained EU law and pre-Brexit domestic law, retained EU law prevails.
- However, new Acts of Parliament or statutory instruments made after IP completion day are not subject to the supremacy of retained EU law, and parliamentary sovereignty is thereby reaffirmed: Parliament can legislate to override or amend retained EU law if it so wishes.
- The principle of supremacy operates only so far as the relevant provisions of retained EU law have not themselves been modified or revoked on or after IP completion day.
Key Term: supremacy of retained EU law
The rule that retained EU law, so far as it has not been amended or revoked, takes precedence over pre-Brexit domestic law in the event of conflict, but does not override statutes enacted after IP completion day.
Worked Example 1.2
A 2015 UK statute, passed before Brexit, conflicts with an EU regulation that became retained EU law. Which prevails?
Answer:
The retained EU regulation prevails over the 2015 Act, because supremacy continues to apply in respect of pre-Brexit domestic law.
Worked Example 1.3
A 2022 UK statute is inconsistent with a rule of retained EU law. Which applies?
Answer:
The 2022 Act prevails. As it was enacted after IP completion day, Parliament's more recent intent takes precedence unless Parliament explicitly incorporates retention of supremacy into the new Act.
Scope and Limits
This principle only applies "so far as relevant"—that is, to the extent there is a direct conflict. Further, the concept of implied repeal (that a later Act overrides an earlier one to the extent of inconsistency) remains relevant except where constitutional statutes are involved. Some case law (e.g., Thoburn v Sunderland City Council) suggests that certain important statutes—including the European Union (Withdrawal) Act 2018 itself—enjoy a quasi-constitutional status and are not subject to implied repeal, but this is not an absolute bar on explicit repeal or amendment.
Interpretation and Case Law
UK courts must interpret retained EU law in line with "retained EU case law" and general principles, unless and until they determine that it is right to depart. "Retained EU case law" comprises Court of Justice of the European Union (CJEU) or domestic decisions on EU law made before IP completion day.
The Supreme Court and the High Court of Justiciary in Scotland (in certain circumstances) may depart from retained EU case law (i.e., CJEU case law as it stood at IP completion day), applying the same principles as when departing from their own previous decisions. Following later regulatory amendments, some other appellate courts may also be permitted to do this in limited situations, for instance the Court of Appeal.
Lower courts, in contrast, remain bound by retained EU case law as it stood at IP completion day, unless higher courts have departed from it.
Key Term: retained EU case law
Decisions of the CJEU and UK courts concerning EU law, handed down before IP completion day and preserved for purposes of interpreting retained EU law post-Brexit.
Statutory interpretation of retained EU law takes a purposive approach, reflecting the method historically used by the CJEU. UK courts are expected to interpret retained EU legislation in accordance with its wording and purpose, and by reference to pre-Brexit CJEU judgments and retained EU general principles (such as proportionality, legal certainty, and fundamental rights), to the extent that these remain part of retained law.
Post-Brexit CJEU case law may be taken into account by UK courts, but is not binding; it is considered persuasive only. UK courts must therefore critically assess whether adherence to retained EU case law continues to be coherent in light of post-Brexit legislative change and UK constitutional principles.
Significance for Proceedings
This approach to interpretation has both practical and constitutional effects: it ensures that the retained EU law remains coherent and consistent, fosters legal certainty, and provides a basis for challenging UK actions (including government decision-making) through domestic courts by reference to pre-Brexit EU jurisprudence.
Categories of Retained EU Law
Retained EU law is categorised for the purposes of amendment and legal status:
- EU-derived domestic legislation: Maintains its prior status as either primary or secondary legislation, with all the implications for who can amend or repeal it and through what process.
- Direct EU legislation: Treated as a new category of UK law—subdivided into "principal" and "minor" retained direct EU legislation:
- Principal retained EU legislation includes most retained EU regulations and certain substantial instruments. Amendments tend to require primary legislation, although some delegated powers exist.
- Minor retained EU legislation covers retained tertiary acts (such as EU implementing or delegated acts) and certain retained EU decisions. These may often be amended through secondary legislation.
- Other retained EU rights: Treated similarly to direct EU legislation for most purposes, and generally ranks above pre-Brexit domestic law, retaining limited supremacy.
Key Term: principal retained EU legislation
Retained direct EU legislation, primarily regulations, generally subject to amendment or repeal only by primary legislation, except where express secondary powers are granted.Key Term: minor retained EU legislation
Retained direct EU legislation consisting mainly of EU tertiary acts or decisions, which may usually be amended by secondary legislation, such as statutory instruments.
This classification affects not only the process for amending the retained legislation but also its standing in the legal hierarchy, and the remedies available in respect of possible breaches.
Amending and Repealing Retained EU Law
Ministers—and, where devolved powers allow, devolved authorities—are given specific, but time-limited, powers to amend retained EU law using secondary legislation. These powers exist mainly to correct deficiencies, such as references to EU institutions or frameworks that no longer apply to the UK, provisions requiring reciprocal recognition which is no longer in place, or regulations depending on the UK's status as an EU member. Such amendments cannot be used to make broad policy changes without explicit statutory authority.
Parliament, exercising sovereignty, can always amend or repeal retained EU law (including constitutional statutes) via a subsequent statute, subject only to the usual political and constitutional limits. As well, a distinction is made between amending primary and secondary retained EU law: amending the former typically requires a further Act of Parliament.
Limitations
Powers to amend retained EU law using secondary legislation (such as the "deficiencies" power in s.8 EUWA 2018) are generally time-limited and subject to scrutiny. They cannot be used to make substantive new law except within the scope specifically allowed by the Withdrawal Act. Substantial changes, especially in matters of public policy or rights, ordinarily require primary legislation.
Practical Application
Solicitors and legal advisers must often determine whether a dispute involves retained EU law, and whether the hierarchy and application of legal principles means that retained EU law will prevail over pre-Brexit UK statutes, or whether subsequent UK legislation has removed, replaced, or modified the relevant retained rule. The practical importance is especially evident in fields deeply affected by EU regulation, such as employment law, consumer rights, environmental obligations, and cross-border litigation.
Assessing whether UK, devolved, or retained EU law prevails in a given situation may depend on the precise dates of the relevant legislation, the scope of any amending Acts or statutory instruments, and the ongoing applicability of pre-Brexit case law and remedial provisions.
Where there is tension between pre-Brexit and post-Brexit legislation and there is no clear resolution in retained EU law, parliamentary sovereignty applies; retained EU law will only prevail where the conflict is with pre-IP completion day legislation, and only insofar as the relevant provision has not been revoked, amended, or superseded.
Worked Example 1.4
A client is involved in an equality claim based on a right recognised in Article 157 TFEU, now "retained EU law", but the Equality Act 2010 offers less protection in respect of a particular aspect. Can the client rely on the wider EU right?
Answer:
If the right under Article 157 TFEU was recognised as directly effective and enforced in UK courts before IP completion day, it is preserved as a retained EU right under s.4 EUWA 2018. If UK domestic law offers less protection and the conflict is with pre-Brexit UK law, the retained EU law right would prevail.
Key Point Checklist
This article has covered the following key knowledge points:
- Retained EU law is the body of law constructed by the European Union (Withdrawal) Act 2018 to ensure continuity after Brexit.
- The three main sources of retained EU law are: EU-derived domestic legislation (s.2 EUWA 2018), direct EU legislation (s.3 EUWA 2018), and other retained EU rights (s.4 EUWA 2018).
- Direct EU legislation includes both principal and minor instruments; EU-derived domestic legislation maintains its original status for amendment purposes.
- Retained EU law preserves a limited form of supremacy: it prevails over pre-Brexit UK statutes but not over new post-Brexit enactments.
- UK courts must interpret retained EU law consistently with pre-Brexit EU case law and general principles, unless and until a higher court departs from such precedent.
- The categories of retained EU law determine how laws can be amended or repealed, and who may do so.
- Ministers have time-limited powers to correct deficiencies in retained EU law.
- Practical application of retained EU law requires careful assessment of the relevant source, status, hierarchy, and possibility of override by subsequent UK law, especially in client advice and litigation contexts.
Key Terms and Concepts
- retained EU law
- EU-derived domestic legislation
- direct EU legislation
- principal retained EU legislation
- minor retained EU legislation
- retained EU rights
- s.2 EUWA 2018
- s.3 EUWA 2018
- s.4 EUWA 2018
- supremacy of retained EU law
- retained EU case law