Constitutional statutes and implied repeal (Thoburn)

This note examines one of the most significant constitutional innovations of the early twenty-first century: the doctrine that certain statutes enjoy a 'constitutional' status that insulates them from the ordinary operation of implied repeal. The doctrine emerged in Thoburn v Sunderland City Council [2002] EWHC 195 (Admin), [2003] QB 151, in which Laws LJ articulated a two-tier hierarchy of legislation and suggested that constitutional statutes could be amended or repealed only by express words or necessary implication.

The significance of Thoburn lies not merely in its immediate effect — preserving the European Communities Act 1972 from alleged implied repeal — but in its challenge to orthodox Diceyan theory. If parliamentary sovereignty means that no Parliament can bind its successors, and that each Act has equal legal status, how can the courts identify a subset of legislation as 'constitutional' and treat it differently? The question goes to the heart of debates explored in Week 1: is sovereignty a political fact (Wade, Goldsworthy) or a common law construct (Allan, Craig)?

This note proceeds in four movements. First, it situates Thoburn within the historical development of the implied repeal doctrine, tracing the line from Vauxhall Estates and Ellen Street Estates through to the anomalous treatment of the European Communities Act. Second, it analyses the constitutional statutes doctrine itself: its criteria, rationale, and doctrinal foundations. Third, it engages with the academic debate that Thoburn has provoked, particularly its implications for sovereignty theory and the common law constitutionalist project. Finally, it explores practical applications through worked examples and identifies common pitfalls in examination answers.

By the end of this note, you should be able to: (i) explain the orthodox implied repeal doctrine and its constitutional foundations; (ii) analyse the reasoning in Thoburn and identify which statutes qualify as 'constitutional'; (iii) critically assess whether Thoburn represents continuity or rupture with traditional sovereignty theory; (iv) apply the doctrine to hypothetical legislative conflicts; and (v) engage with the ongoing debate about the normative basis of constitutional statutes.

The doctrine of implied repeal is a corollary of parliamentary sovereignty. Because Parliament cannot bind its successors as to the manner and form of legislation, a later statute inconsistent with an earlier one will, to the extent of the inconsistency, impliedly repeal the earlier provision — even if Parliament did not consciously intend that result. This principle, confirmed in Vauxhall Estates Ltd v Liverpool Corporation [1932] 1 KB 733 and Ellen Street Estates Ltd v Minister of Health [1934] 1 KB 590, reflects Dicey's vision of a legally omnipotent and continuing Parliament.

In Ellen Street Estates, Maugham LJ held that the Housing Act 1925, s. 46, which provided that its provisions should have effect 'notwithstanding anything in any Act', could not prevent implied repeal by the Housing Act 1930. The 1925 Parliament could not 'entrench' its own legislation against future amendment. This remains the orthodox position: formal legislative equality means that even express 'ouster' clauses cannot bind future Parliaments.

Yet the doctrine has always sat uneasily with fundamental constitutional instruments. Would Parliament really intend to repeal Magna Carta, the Bill of Rights 1689, or the Act of Settlement 1700 by passing an inconsistent traffic regulation? Dicey himself acknowledged that 'constitutional laws' existed but insisted they had no special legal status — a distinction that became increasingly unsustainable as the statute book grew.

The accession to the European Communities in 1973 posed the question acutely. The European Communities Act 1972, s. 2(1) and (4), gave directly effective EU law supremacy over domestic legislation, including future Acts. Could Parliament entrench this supremacy rule, or would a later inconsistent Act impliedly repeal the ECA 1972? In Macarthys Ltd v Smith [1979] 3 All ER 325, Lord Denning MR suggested that courts should construe later statutes, if possible, to conform with EU law; only an express declaration of intention to repeal the ECA would suffice. This was a strained reading of Ellen Street Estates, but it hinted at a new interpretive principle.

The tension came to a head in Factortame (No 2) [1991] 1 AC 603, where the House of Lords disapplied the Merchant Shipping Act 1988 to comply with directly effective EU law. This looked suspiciously like implied repeal in reverse: the ECA 1972, an earlier statute, prevailing over a later one. Orthodox sovereignty theory struggled to explain the result. Wade argued that Factortame represented a constitutional 'revolution'; Craig and others contended it was reconcilable with continuing parliamentary sovereignty if one read s. 2(4) as a manner-and-form rule (Week 1).

By the late 1990s, further constitutional statutes — the Human Rights Act 1998, the Scotland Act 1998, the Government of Wales Act 1998 — had entered the statute book. Each was 'ordinary' legislation in form, yet plainly not ordinary in substance. Thoburn provided the doctrinal tools to acknowledge this distinction.

The Thoburn framework

Thoburn v Sunderland City Council [2002] EWHC 195 (Admin), [2003] QB 151 arose from the 'metric martyrs' litigation. Market traders challenged convictions for using imperial measures, arguing that the Weights and Measures Act 1985 (as amended to require metric units pursuant to EU law) had impliedly repealed the ECA 1972. Laws LJ rejected the argument and articulated the constitutional statutes doctrine.

At [62]–[63], Laws LJ distinguished between 'ordinary' statutes and 'constitutional' statutes:

'In the present state of its maturity the common law has come to recognise that there exist rights which should properly be classified as constitutional or fundamental... And from this a further insight follows. We should recognise a hierarchy of Acts of Parliament: as it were "ordinary" statutes and "constitutional" statutes.'

A constitutional statute is one which (a) conditions the legal relationship between citizen and State in some general, overarching manner, or (b) enlarges or diminishes the scope of fundamental constitutional rights. Examples given by Laws LJ include Magna Carta, the Bill of Rights 1689, the Acts of Union 1706–07, the Reform Acts, the Human Rights Act 1998, the Scotland Act 1998, and the Government of Wales Act 1998.

The legal consequence is stated at [63]:

Foundation

1. What is the doctrine of implied repeal, and why did the courts in Vauxhall Estates and Ellen Street Estates refuse to allow earlier Parliaments to entrench their legislation against implied repeal?

2. Explain the test articulated by Laws LJ in Thoburn for identifying a 'constitutional statute'. Give three examples of statutes that satisfy the test.

Standard

3. 'The constitutional statutes doctrine in Thoburn is best understood as an interpretive presumption, not a rule of validity.' Discuss.

4. To what extent has the UK Supreme Court endorsed the reasoning in Thoburn? Consider the relevant dicta in HS2 Action Alliance and Miller I.

Challenge

5. 'Thoburn represents a significant departure from Diceyan parliamentary sovereignty, yet it has had little practical impact on Parliament's ability to legislate. This paradox reveals the limits of legal doctrine in shaping constitutional practice.' Discuss with reference to the European Union (Withdrawal) Act 2018 and other recent constitutional legislation.

Essential

• Laws LJ, Thoburn v Sunderland City Council [2002] EWHC 195 (Admin), [2003] QB 151 (read [59]–[69] closely)
• Elliott, M., 'The Principle of Parliamentary Sovereignty in Legal, Constitutional, and Political Perspective' in Jowell & Oliver (eds), The Changing Constitution (8th edn, OUP 2015) ch 2 (pp 38–78)
• Craig, P., 'Constitutionalising Constitutional Law: HS2' [2014] Public Law 373

Advanced

• Allan, T.R.S., 'Constitutional Dialogue and the Justification of Judicial Review' (2003) 23 Oxford Journal of Legal Studies 563
• Goldsworthy, J., Parliamentary Sovereignty: Contemporary Debates (CUP 2010), especially chs 1–3 and ch 13 (Goldsworthy's response to common law constitutionalism)
• Young, A.L., 'Hunting Sovereignty: Jackson v Her Majesty's Attorney General' [2006] Public Law 187 (excellent analysis of the relationship between Jackson dicta and Thoburn)
• Elliot, M., 'Bicameralism, Sovereignty and the Unwritten Constitution' (2007) 5 International Journal of Constitutional Law 370 (on manner and form)

Comparative and theoretical

• Barber, N.W., 'The Afterlife of Parliamentary Sovereignty' (2011) 9 International Journal of Constitutional Law 144 (argues that Thoburn and related developments have fundamentally altered UK sovereignty)
• Lakin, S., 'Debunking the Idea of Parliamentary Sovereignty: The Controlling Factor of Legality in the British Constitution' (2008) 28 Oxford Journal of Legal Studies 709 (common law constitutionalist account)

Historical context

• Wade, H.W.R., 'The Basis of Legal Sovereignty' [1955] Cambridge Law Journal 172 (classic statement of the 'rule of recognition' as political fact)
• Wade, H.W.R., 'Sovereignty — Revolution or Evolution?' (1996) 112 Law Quarterly Review 568 (Factortame as revolution)

Note: readings marked 'Essential' are strongly recommended for all FHS candidates. 'Advanced' readings are for those seeking first-class marks or with particular interest in sovereignty theory. 'Comparative and theoretical' materials enrich understanding but are not necessary for competent exam performance.