Introduction
The judgment in Thoburn v Sunderland City Council is a landmark decision in UK public law, addressing the relationship between domestic legislation and European Union (EU) law. The case concerned the legality of using imperial measurements for trade, which brought into conflict the provisions of the Weights and Measures Act 1985 and regulations made under the European Communities Act 1972 (ECA 1972). This note will explain the court’s decision and analyse its significant contribution to constitutional law, particularly through Laws LJ’s introduction of the concept of ‘constitutional statutes’, which modified the traditional doctrine of implied repeal.
Factual and Legislative Background
The appellants, a group of market traders often called the ‘metric martyrs’, were convicted for using weighing machines that only showed imperial units (pounds and ounces). Their defence was that the Weights and Measures Act 1985 (the 1985 Act) permitted the continued use of such units. However, the prosecutions were brought under the Units of Measurement Regulations 1994 (the 1994 Regulations), secondary legislation made under section 2(2) of the ECA 1972. These regulations implemented an EU Directive requiring the use of metric units.
The central legal issue was a conflict between two Acts of Parliament. The ECA 1972, which gave effect to EU law, seemed to conflict with the later 1985 Act. The traders argued that under the doctrine of implied repeal, the provisions of the later 1985 Act should prevail over the earlier ECA 1972. This would mean that any part of the 1972 Act inconsistent with the 1985 Act was implicitly repealed, making the 1994 Regulations invalid to the extent they contradicted the 1985 Act.
The Judgment of the Divisional Court
The Divisional Court upheld the convictions, finding that the 1994 Regulations were valid and had effectively overridden the conflicting provisions of the 1985 Act. The leading judgment was given by Laws LJ, who addressed the constitutional question of implied repeal directly.
Laws LJ rejected the argument that the 1985 Act had impliedly repealed section 2(2) of the ECA 1972. He did so by proposing a hierarchy of statutes, distinguishing between "ordinary" statutes and "constitutional" statutes. He stated that ordinary statutes can be impliedly repealed by a later inconsistent statute. However, he argued that constitutional statutes could not be.
He defined a constitutional statute as one which "conditions the legal relationship between citizen and state in some general, overarching manner, or (b) enlarges or diminish the scope of what we would now regard as fundamental constitutional rights" (Thoburn, at [62]). He gave examples including Magna Carta, the Bill of Rights 1689, the Human Rights Act 1998, and, crucially for this case, the ECA 1972.
According to Laws LJ, such fundamental statutes could only be repealed by express provision in a subsequent Act of Parliament. A 'constitutional' statute could not be repealed by implication. Since the ECA 1972 was a constitutional statute, it was not subject to implied repeal by the later 1985 Act. Therefore, section 2(2) of the ECA 1972 remained in force, providing the legal basis for the 1994 Regulations which, in line with the principle of the supremacy of EU law, took precedence over the 1985 Act.
Analysis and Significance
The decision in Thoburn is significant because it represents a judicial modification of the traditional doctrine of parliamentary sovereignty. The orthodox view, associated with A.V. Dicey, is that Parliament is legally supreme and cannot bind its successors; therefore, any Act can be repealed by a later Act, either expressly or by implication (Vauxhall Estates Ltd v Liverpool Corporation [1932] 1 KB 733).
Laws LJ’s judgment qualifies this principle. While he affirmed that Parliament remains sovereign and can repeal any statute, including a constitutional one, he established a new rule of statutory interpretation. To repeal a constitutional statute, Parliament must use express words, making its intention to do so clear and unambiguous. This creates a ‘manner and form’ requirement for the repeal of certain fundamentally important laws (Elliott and Thomas, 2020). This protects key statutes from being repealed accidentally or in a "side-wind" (Thoburn, at [63]).
This approach was a bold an-d creative judicial step. It sought to reconcile the traditional view of parliamentary sovereignty with the practical reality of the UK’s membership of the EU, which required UK courts to give EU law priority. While the UK has now left the EU, the concept of a hierarchy of statutes developed in Thoburn has remained influential, being cited in later major constitutional cases such as R (Miller) v Secretary of State for Exiting the European Union [2017] UKSC 5.
Conclusion
Thoburn v Sunderland City Council is a key case in modern UK constitutional law. By introducing the category of 'constitutional statutes' which are immune from implied repeal, Laws LJ provided a legal solution to the conflict between domestic and EU law while also creating a mechanism to protect the UK’s most fundamental laws. The decision represents a significant development in the doctrine of parliamentary sovereignty, showing how the judiciary can adapt long-standing constitutional principles to new legal and political realities.
References
- Elliott, M. and Thomas, R. (2020) Public Law. 4th edn. Oxford University Press.
- R (Miller) v Secretary of State for Exiting the European Union [2017] UKSC 5.
- Thoburn v Sunderland City Council [2002] EWHC 195 (Admin), [2003] QB 151.
- Vauxhall Estates Ltd v Liverpool Corporation [1932] 1 KB 733.
