Introduction
The concepts of constitutional supremacy and the rule of law are fundamental pillars of modern democratic states. While distinct, they are deeply interconnected and mutually dependent. The rule of law requires that all, including the government, are subject to and governed by the law. Constitutional supremacy establishes the constitution as the highest law of the land, providing the legal limits that the rule of law demands. This essay will explain the relationship between these principles, following the chain of logic from the rule of law to the establishment of stable government. It will argue that these concepts are mutually reinforcing, and the absence of one significantly weakens the other, even within the unique constitutional arrangements of the United Kingdom.
The Rule of Law and the Need for Legal Limits
The rule of law is a principle of governance which dictates that state power should not be exercised arbitrarily, but rather in accordance with established laws. A.V. Dicey, a prominent jurist, identified three core tenets: the absolute supremacy of regular law over arbitrary power, equality before the law for all citizens, and the protection of individual rights through the ordinary courts (Dicey, 1885). More recently, Lord Bingham expanded on this, proposing eight sub-rules, including that the law must be clear, accessible, and predictable, and must afford adequate protection for fundamental human rights (Bingham, 2010). A central thread in all definitions is that the government itself must be bound by law. For this to be a reality, there must be a source of law that defines and limits the powers of the state’s institutions, namely the legislature, executive, and judiciary.
The Constitution as a Provider of Legal Limits
In many countries, such as the United States and Germany, a written constitution serves as this higher law. Under the doctrine of constitutional supremacy, the constitution is the ultimate source of legal authority. Any action or law passed by the government or legislature that conflicts with the constitution is invalid. The constitution thus provides clear, enforceable legal limits on state power, turning the abstract ideal of the rule of law into a concrete legal reality.
The United Kingdom’s position is different, as it operates under the principle of parliamentary supremacy, where Parliament is the supreme law-making body and no court can strike down an Act of Parliament. However, this does not mean there are no legal limits. The UK has an ‘unwritten’ constitution comprised of statutes, common law, conventions, and authoritative works. Certain statutes are considered to have a special ‘constitutional’ status, such as the Magna Carta 1297, the Bill of Rights 1689, and the Human Rights Act 1998 (HRA 1998). These acts establish fundamental rights and principles that limit the government, thereby serving a similar function to a written constitution in upholding the rule of law.
Courts as Enforcers of the Constitution
For constitutional limits to be effective, an independent judiciary must have the power to enforce them. In systems with constitutional supremacy, this power of judicial review allows courts to invalidate legislation that is unconstitutional. In the UK, while courts cannot invalidate primary legislation, they play a crucial role in upholding the rule of law by ensuring the executive acts within the powers granted to it by Parliament. Through the mechanism of judicial review, courts can quash decisions of public bodies that are illegal, irrational, or procedurally improper. Furthermore, under section 4 of the HRA 1998, higher courts can issue a ‘declaration of incompatibility’ if a provision of an Act of Parliament conflicts with a right under the European Convention on Human Rights. While this does not invalidate the Act, it puts strong political pressure on Parliament to amend the law. The Supreme Court's decision in R (Miller) v The Prime Minister [2019] UKSC 41, which held that the Prime Minister's advice to prorogue Parliament was unlawful because it frustrated the constitutional principle of parliamentary sovereignty, demonstrates the judiciary’s role in enforcing fundamental constitutional limits even in the absence of a codified constitution.
Protection of Rights and Stable Government
This interconnected system, where the rule of law is given structure by a constitution and upheld by the courts, is essential for protecting citizens’ rights and fostering a stable society. When the government is bound by law and individuals have access to independent courts to challenge unlawful state action, rights are safeguarded against arbitrary interference. This legal certainty and protection allows individuals and businesses to plan their affairs with confidence, encouraging economic activity and social cohesion. Trust in legal and political institutions is maintained, which is the foundation of a stable and prosperous government.
Conclusion: A Symbiotic Relationship
In conclusion, constitutional supremacy and the rule of law are symbiotically linked. The rule of law provides the normative justification for limited government, while a constitution provides the concrete legal framework for those limits. The courts act as the essential enforcement mechanism, giving life to the constitutional text. This relationship creates a virtuous circle: the rule of law requires a supreme constitution, which in turn depends on the rule of law for its own efficacy, as a constitution that is routinely ignored is merely a document of "words on paper" (Bradley, Ewing and Knight, 2018). Together, they form the bedrock of a legal system that protects rights, holds power to account, and ensures the stability and legitimacy of the state.
References
Bingham, T. (2010) The Rule of Law. Allen Lane.
Bradley, A., Ewing, K. and Knight, C. (2018) Constitutional and Administrative Law. 17th edn. Pearson.
Dicey, A.V. (1885) An Introduction to the Study of the Law of the Constitution. Macmillan.
Human Rights Act 1998.
R (Miller) v The Prime Minister [2019] UKSC 41.
