Parliament and parliamentary sovereignty - Principles of par...

Learning Outcomes

This article explains the doctrine of parliamentary sovereignty within the UK constitutional framework, essential for understanding public law and its application in legal practice. It enables you to articulate and critically analyse the elements of A.V. Dicey's classic conception of parliamentary sovereignty, including Parliament's legislative supremacy—the power to make, unmake, or repeal any law. It also clarifies the principle that the validity of an Act of Parliament cannot be challenged by courts or any other body, and explores the doctrine that no Parliament can bind its successors, including mechanisms of repeal.

A thorough understanding of the relationship between Parliament and the courts is provided, focusing on the application and limits of the 'enrolled Act' rule. The article also explores how courts interpret and apply legislation, and how doctrines such as implied repeal operate—highlighting the recent recognition of 'constitutional statutes' as a possible limit to this doctrine. You will gain practical and legal limitations affecting parliamentary sovereignty, including the influence of the Human Rights Act 1998, devolution, and the historical impact and legacy of EU membership ('retained EU law').

Further, the article provides a critical approach for understanding how these doctrines influence other constitutional principles such as the separation of powers and the rule of law. Through worked examples, you will be able to apply these doctrines to hypothetical scenarios and appreciate their practical consequences within the English legal system.

SQE1 Syllabus

For SQE1, you are required to understand the principles of parliamentary sovereignty within the UK constitutional framework, with a focus on the following syllabus points:

• the meaning and historical origins of parliamentary sovereignty within the UK’s unwritten constitution
• A.V. Dicey's formulation and the three central limbs of the doctrine: legislative supremacy, inability of Parliament to bind its successors, and prohibition on judicial override of statutory law
• the doctrine of implied repeal, how it is constrained for 'constitutional statutes', and when express repeal is needed
• the relationship between parliamentary sovereignty and the roles of Parliament, the courts, and the executive, including the 'enrolled Act' rule and parliamentary privilege
• practical and legal limitations on parliamentary sovereignty, such as the Human Rights Act 1998, constitutional statutes, judicial review of secondary legislation, devolution and political conventions
• the impact of EU law on sovereignty, both during membership (Factortame line of authority) and post-Brexit as retained EU law
• application of these principles to problem-based scenarios, including recognition of where theoretical and practical limits may diverge
• the interaction of sovereignty with the rule of law, constitutional conventions, and developments in legal thinking.

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.

1. Which element is NOT part of A.V. Dicey's classic definition of parliamentary sovereignty?
   1. Parliament can make or unmake any law.
   2. The courts can invalidate an Act of Parliament if it breaches fundamental rights.
   3. No Parliament can bind a future Parliament.
   4. No person or body can override an Act of Parliament.
2. The 'Enrolled Act' rule, established in cases like Pickin v British Railways Board, means that:
   1. Courts must enroll all new Acts onto a special register.
   2. Courts cannot investigate the internal parliamentary procedure used to pass an Act.
   3. Only enrolled solicitors can challenge Acts of Parliament.
   4. Acts are valid only if enrolled within six months of Royal Assent.
3. Which of the following represents a legal limitation on Parliament's ability to legislate?
   1. A resolution passed by the House of Commons.
   2. A strongly worded constitutional convention.
   3. The requirement under the Human Rights Act 1998 for courts to interpret legislation compatibly with Convention rights where possible.
   4. Public opinion opposing a proposed Bill.

4. True or false? The doctrine of implied repeal means that a 'constitutional statute' (as discussed in Thoburn) can be overridden by any later inconsistent Act of Parliament, even if the later Act does not expressly state this.

Introduction

Parliamentary sovereignty, often termed ‘parliamentary supremacy’, is central to the United Kingdom’s uncodified constitution. This core constitutional doctrine affirms that Parliament—the ‘Queen in Parliament’, consisting of the monarch, House of Commons, and House of Lords—has ultimate legal authority to make or unmake any law on any subject. In theory, there is no legal limit on the topics Parliament may legislate upon or the manner and extent of such lawmaking. The principle means that Parliament’s enactments are the supreme source of law; no other institution, including the judiciary, has authority to invalidate or set aside an Act of Parliament.

The historical development of this concept is entwined with key statutes such as the Bill of Rights 1689, the Act of Settlement 1701, the Parliament Acts 1911 and 1949, and more recent innovations such as the Human Rights Act 1998. Parliamentary sovereignty is not an isolated principle, but functions alongside other structural concepts, such as the separation of powers, the rule of law, and the role of constitutional conventions. In the UK, the doctrine has been continually debated, critiqued, and adapted to meet the complexities of modern governance, including challenges posed by devolution, international treaties, the influence of supranational law, and changing political and societal realities.

Key Term: Parliamentary sovereignty
The constitutional principle that the UK Parliament is the supreme legal authority, capable of creating or ending any law, whose enactments cannot be overridden or set aside by any other body, including the courts.

The Traditional Doctrine: Dicey's Formulation

A.V. Dicey’s influential 19th-century statement of parliamentary sovereignty forms the doctrinal core of the UK constitution. Dicey identified three essential features:

1. Parliament can make or unmake any law whatsoever: Parliament’s legislative authority is unlimited by subject matter or question of policy. It can legislate on any issue, even on matters contrary to previous statutes, international law, or fundamental rights and principles.
2. No person or body can override or set aside the legislation of Parliament: The validity of a statute cannot be challenged by the courts or any other body. The will of Parliament expressed in statute is the highest and only law.
3. No Parliament can bind its successors or be bound by its predecessors: Each new Parliament is sovereign and cannot be restricted by previous Parliaments. It follows that no Parliament can entrench a law that future Parliaments cannot amend or repeal.

Key Term: Legislative supremacy
The principle that Parliament's law-making authority is supreme over all other sources of law, including common law, conventions, and international agreements, within the UK's constitutional order.

Dicey’s concept also included the idea that Parliament does not share its law-making powers with any other body, and that sovereignty is continuous and indivisible. This classical view has been subject to sustained pressure and some judicial reinterpretation, but remains a benchmark for UK constitutional analysis.

Legislative Supremacy in Practice

The legislative supremacy of Parliament is clear in practice, as it means there are no substantive limits—legal or ethical—on the laws Parliament can pass. The courts will enforce an Act of Parliament, even if its outcome is repugnant, offensive to human rights, or overrides common law. Notably, Parliament can legislate retroactively, change the law for the whole UK or specific jurisdictions, and repeal or modify statutes of constitutional significance. This has permitted significant change—from the abolition of slavery, to women’s suffrage, to the Brexit process.

Extra-territorial and Retrospective Laws

Diceyan sovereignty also means Parliament can enact laws with effects outside the UK, or laws with retrospective effect. While political and international constraints exist, no legal limitation stops Parliament from doing so. For example, the War Crimes Act 1991 extended UK law’s reach to crimes committed during World War II in Nazi-occupied Europe, and the War Damage Act 1965 operated retrospectively to overturn a judicial decision in Burmah Oil Co v Lord Advocate.

Statutory Supremacy over Common Law and the Royal Prerogative

Acts of Parliament always take precedence over common law rules and the royal prerogative. For instance, legislative reforms have replaced or abrogated many prerogative powers, such as the abolition of judicial office ‘at pleasure’ by the Act of Settlement 1701, and the restriction of the monarch’s ability to dissolve Parliament by the since-repealed Fixed-term Parliaments Act 2011.

No Parliament Binding Successors: The 'Implied Repeal' Doctrine

Dicey’s third limb underlines that no Parliament can enact a law immune from future amendment or repeal. This tenet is operationalised through the doctrines of ‘implied repeal’ and ‘express repeal’.

Key Term: Implied repeal
If a later Act of Parliament conflicts with an earlier Act, the later Act prevails, and the earlier, inconsistent statutory provision is considered repealed to the extent of the inconsistency, even if the later Act does not expressly state this.

The doctrine applies automatically: unless a statute stipulates that an earlier Act is expressly repealed, incompatibility between statutes will be resolved in favour of the most recent. There is, in effect, no substantive entrenchment—each Parliament can undo the work of its predecessors by subsequent statute.

Express Repeal

An Act can specifically stipulate the repeal of earlier statutes by referring to them by name and stating that they are no longer law. This approach is commonly used for clarity but, in its absence, implied repeal may operate.

Worked Example 1.1

The (fictitious) Public Health Act 2010 mandates that all public swimming pools must install specific safety equipment by 2015. In 2018, Parliament passes the (fictitious) Leisure Facilities Act 2018, which sets out different, less stringent requirements for safety equipment in all leisure facilities, including swimming pools, and makes no mention of the 2010 Act. A local council pool, opened in 2019, complies only with the 2018 Act's requirements.

Is the council in breach of the 2010 Act?

Answer:
No. Where two statutes are inconsistent, the later in time is given priority to the extent of any conflict (implied repeal). As the 2018 Act sets out different requirements for swimming pools and is the later statute, any irreconcilable provisions of the earlier Act are considered repealed. The council, by complying with the 2018 Act, is not in breach of the 2010 Act.

The Role of Courts: The 'Enrolled Act' Rule

The courts have traditionally upheld the legislative supremacy of Parliament by refusing to question the validity of an enacted statute. This is known as the 'enrolled Act' rule.

Key Term: Enrolled Act rule
Once a Bill has passed through all stages in Parliament and received Royal Assent, the courts will not inquire into its procedural history or validity—the Act is conclusive on its face and treated as valid law.

This rule is rooted in decisions such as Edinburgh & Dalkeith Railway Co v Wauchope (1842) and Pickin v British Railways Board [1974] AC 765. The effect is that challenges based on Parliament's legislative process, failure to comply with standing orders, or alleged fraud during passage are inadmissible. The courts look only to the Parliamentary roll: if an Act appears there, it is law.

Exclusion of Judicial Review

Unlike many written constitutions (such as that of the United States), the UK tradition has been not to allow judicial review of primary legislation on grounds of substance or procedure. There is no domestic mechanism for a court to declare an Act ‘void’ or unconstitutional—only Parliament can amend or repeal its own enactments.

Parliamentary Privilege

Parliament also enjoys extensive privilege, ensuring independence in its legislative and deliberative functions. Article 9 of the Bill of Rights 1689 protects free speech in Parliament from being questioned in courts. The doctrine of ‘exclusive cognisance’ means Parliament controls its internal proceedings and membership. The courts will not intervene in internal parliamentary discipline or procedure (except in criminal matters unrelated to core functions, as seen in R v Chaytor [2010] UKSC 52).

Worked Example 1.2

A member of the public claims that they were not notified that an Act of Parliament affecting their property rights was being considered, in breach of Parliament’s standing orders, and seeks a judicial declaration that the Act is invalid.

Answer:
The enrolled Act rule prevents judicial investigation of Parliamentary procedure. The courts will not inquire into whether Parliament complied with its standing orders or consultative procedures; once Royal Assent has been given, the Act is valid and cannot be questioned.

Limitations and Challenges to Parliamentary Sovereignty

Although Parliament’s sovereignty is legally absolute in theory, significant legal and practical constraints have arisen in practice—some internal to the UK system, others from broader developments in constitutional law.

Political and Practical Limits

In reality, Parliament operates within a web of political restraints: public opinion, the threat of electoral consequences, principles of constitutional morality, and adherence to conventions and democratic legitimacy. Parliament may be theoretically omnipotent, but it is practically unlikely to pass laws that are profoundly unpopular or ungovernable without risking its own authority.

Devolution

The devolution settlements of the late 1990s (the Scotland Act 1998 et seq., the Government of Wales Act 1998, the Northern Ireland Act 1998) transferred broad law-making powers to devolved legislatures. Each devolution statute contains affirmations of parliamentary sovereignty (e.g., s 28(7) Scotland Act 1998 specifies that Westminster can still legislate for Scotland), and s 1 of the Scotland Act 2016 recognises the Scottish Parliament and Government as ‘permanent’ institutions that may only be abolished following a referendum. Despite the political and practical reality that revoking devolved powers is nearly unimaginable, there is no legal entrenchment—Parliament remains legally entitled to legislate over devolved matters or to repeal devolution Acts.

The Sewel Convention

There is a well-established constitutional convention (the Sewel Convention) that Westminster ‘will not normally legislate with regard to devolved matters without the consent of the devolved legislature’. However, the Supreme Court has clarified (Miller (No 1)) that, even though the Sewel Convention is recited in statute, it is not a legally enforceable limit on parliamentary power; its effect is political rather than legal.

EU Membership: The Factortame Principle (Historical Context)

The most prominent modern legal challenge to parliamentary sovereignty came with UK membership of the European Union. The European Communities Act 1972 incorporated EU law as directly effective in the UK and required courts to give it supremacy over inconsistent domestic law (including later Acts, via s.2(4)). In R v Secretary of State for Transport ex parte Factortame Ltd (No 2) [1991] AC 603, the House of Lords held that the UK courts must suspend the operation of inconsistent legislation (the Merchant Shipping Act 1988) where it contradicted EU law, and that this power derived from Parliament’s voluntary grant of legislative authority to the EU. While significant, this supremacy was always contingent on Parliament’s continuing will; it has now been ended by the UK’s withdrawal from the EU and the repeal of the 1972 Act (European Union (Withdrawal) Act 2018). Retained EU law remains, but is now subject to amendment or repeal by Parliament.

Key Term: Retained EU law
EU-derived law that was operative in the UK immediately before ‘exit day’ and preserved temporarily under the European Union (Withdrawal) Act 2018; it may now be amended or repealed by Parliament.

Human Rights Act 1998 (HRA): Interpretative and Political Limits

With the coming into force of the HRA 1998, the UK incorporated most rights guaranteed by the European Convention on Human Rights into domestic law. This statute does not authorise courts to declare primary legislation void, but introduces a substantial 'interpretative obligation' on courts (s.3 HRA):

• Section 3 requires both primary and subordinated legislation to be interpreted ‘so far as it is possible to do so’ in a manner compatible with Convention rights.
• Section 4 enables courts to issue a formal 'declaration of incompatibility' if any provision of legislation cannot be interpreted compatibly, but such a declaration does not invalidate the statute; Parliament remains sovereign to amend or ignore the law in question.

Key Term: Declaration of incompatibility
A statement by a higher court (High Court and above) declaring that a provision of legislation is incompatible with rights under the Human Rights Act 1998, but does not invalidate the legislation—Parliament chooses whether and how to address the incompatibility.

In practice, most declarations of incompatibility have led to Parliament amending the relevant statutes, but Parliament is not legally obliged to do so. The sovereignty of Parliament is preserved, but the HRA has created a powerful norm that legislation should respect fundamental rights.

Worked Example 1.3

Parliament enacts an Act that a court finds incompatible with Article 8 ECHR, and issues a section 4 declaration of incompatibility. Is Parliament required to amend or repeal the statute?

Answer:
No. A declaration of incompatibility does not require Parliament to make any changes. While there may be significant political and reputational pressure to amend the law, Parliament remains legally sovereign and can choose whether to change, retain, or even expand the incompatible law.

Constitutional Statutes: A Judicial Qualification to Implied Repeal

A growing line of judicial reasoning challenges the absolute doctrine of implied repeal for certain 'constitutional' legislation. In Thoburn v Sunderland City Council [2002] EWHC 195 (Admin), Laws LJ distinguished between 'ordinary' statutes and those of 'constitutional' status—such as the Magna Carta, Bill of Rights 1689, Scotland Act 1998, European Communities Act 1972, and Human Rights Act 1998. He suggested that constitutional statutes are not susceptible to implied repeal but can be repealed only by express words or by clear and irresistible implication. This implies, without fully adopting, a latent hierarchy of statutes in UK law—though Parliament, in principle, can always expressly repeal any enactment.

Key Term: Constitutional statutes
Acts of Parliament regarded as fundamental to the constitutional order; courts may require express words in later statutes to revoke or undermine them, resisting implied repeal.

The Supreme Court has shown cautious support for this view, as in R (HS2 Action Alliance Ltd) v Secretary of State for Transport [2014] UKSC 3 and R (Miller) v Secretary of State for Exiting the European Union [2017] UKSC 5. However, the full implications of this idea remain open. While it does not overturn the basic Diceyan model, it does indicate a subtle constraint on how parliamentary sovereignty is operationalised in practice.

Worked Example 1.4

Parliament enacts a Local Government Act containing new electoral rules that conflict with the earlier Representation of the People Act 1983—a constitutional statute—without specifying repeal of the earlier Act. What happens to the conflicting provisions?

Answer:
Where a later Act conflicts with a constitutional statute, the doctrine established in Thoburn means the constitutional statute cannot be overridden by implication. The later Act must contain 'irresistible' language or explicit repeal. In the absence of such, the earlier statute remains in force, and the conflicting provision of the newer Act is ineffective to the extent of the conflict.

Worked Example 1.5

A client argues that the court should declare an Act invalid because Parliament failed to consult widely or to hold a referendum as promised in a political manifesto, before enacting legislation with major constitutional impact. Is this a ground for judicial challenge?

Answer:
No. The courts are concerned with the legality of the Act, not the way Parliament conducted its legislative process, unless non-compliance with procedural requirements is made a condition of legal validity by the Act itself—which is extremely rare. The courts will uphold statutes that have received Royal Assent regardless of manifesto promises, political conventions, or levels of consultation.

Summary: The Changing Character of Sovereignty

While parliamentary sovereignty remains a primary principle of the UK constitutional order, it now exists within a more complex and plural environment. The practical ability of Parliament to do whatever it wishes is heavily mediated by political, international and, increasingly, judicial norms. The Human Rights Act 1998 and the concept of constitutional statutes, in particular, compel Parliament to legislate with greater care for fundamental rights and constitutional principles, reinforcing political constraints with significant legal ones, even as sovereignty is legally preserved.

Cases such as R (Jackson) v Attorney General [2005] UKHL 56 have seen senior judges hint at possible theoretical limits on sovereignty in exceptional circumstances (such as if Parliament were to seek to abolish judicial review or free elections), but such obiter comments have not yet translated into firm law.

Exam Warning
For SQE1, when assessing the limits of parliamentary sovereignty, always distinguish between the traditional, theoretical basis (no legal limits) and the practical and newly evolving legal limits (constitutional statutes, interpretative obligation under HRA 1998, devolution, and retained EU law). Be able to identify when courts apply doctrines such as the enrolled Act rule, or when they are addressing the substantive validity of secondary legislation (judicial review of delegated legislation is possible) rather than that of primary legislation.

Key Point Checklist

This article has covered the following key knowledge points:

• Parliamentary sovereignty remains a key principle: Parliament has the supreme legal authority to make, amend or repeal any law, unconstrained by other bodies.
• Dicey identified three central limbs: legislative supremacy, no judicial or other body’s override, and no Parliament binding its successors.
• The enrolled Act rule prevents the courts from questioning the validity or the process of an Act of Parliament.
• The doctrine of implied repeal means a later Act supersedes prior inconsistent statutes—except potentially for constitutional statutes, which may only be overcome by express wording or irresistible implication.
• Parliamentary sovereignty is constrained in practice by political, international, and legal factors, including interpretative duties under the Human Rights Act 1998, the concept of constitutional statutes, the framework of devolution, and the legacy of EU law and 'retained EU law'.
• Courts can strike down secondary (delegated) legislation for being ultra vires but will not do so for primary legislation except in the rare case of a declaration of incompatibility under the Human Rights Act 1998.
• The scope and content of parliamentary sovereignty continue to be a subject of debate and gradual evolution within the UK’s uncodified constitutional system.

Key Terms and Concepts

• Parliamentary sovereignty
• Legislative supremacy
• Implied repeal
• Enrolled Act rule
• Constitutional statutes
• Declaration of incompatibility
• Retained EU law