The Rule of Law in the British Constitutional Tradition

The rule of law is a fundamental principle of the United Kingdom constitution. Alongside parliamentary sovereignty, it forms one of the twin pillars of British constitutional thought. The principle requires that government power be exercised according to established legal rules rather than arbitrary discretion, and that all persons and institutions are subject to and accountable under the law. It is a concept with both formal and substantive dimensions, and its meaning has been refined over centuries of constitutional development. The rule of law is not merely a political ideal but a legal principle that courts can enforce.

Dicey’s Formulation

A. V. Dicey identified three components of the rule of law. First, no person may be punished except for a distinct breach of law established in ordinary legal proceedings before ordinary courts. This condemns arbitrary executive power and retrospective legislation, ensuring that individuals can only be penalised for conduct that was clearly prohibited at the time it occurred. Second, no person is above the law—all are subject equally to the jurisdiction of the ordinary courts. This principle rejects the idea of separate administrative courts for government officials and holds that ministers and civil servants are answerable to the same courts as ordinary citizens. Third, general constitutional principles are the result of judicial decisions determining the rights of private persons, rather than deriving from a written constitution. For Dicey, the rule of law was intrinsically linked to the common law method and the protection of individual liberty through judicial remedies. His formulation has been criticised for conflating the rule of law with specific features of the English legal system, but it remains influential in understanding the relationship between law and government.

Modern Judicial Development

Contemporary courts have expanded and refined the rule of law. In Entick v Carrington (1765), Lord Camden held that state officials must point to positive legal authority for their actions—they cannot rely on claims of necessity or state interest. This case established the fundamental principle that every invasion of private property, however minute, requires legal justification. In R v Secretary of State for the Home Department, ex parte Pierson (1998), Lord Browne-Wilkinson stated that the rule of law requires that the courts give effect to Parliament’s intention but also requires that the executive act within its powers. The courts will not presume that Parliament intended to authorise arbitrary or discretionary power. In R (UNISON) v Lord Chancellor (2017), the Supreme Court struck down employment tribunal fees as unlawful because they impeded access to justice—a core component of the rule of law. Lord Reed’s judgment in UNISON is a landmark statement of the modern rule of law, affirming that access to the courts is a constitutional right that cannot be removed without compelling justification.

Core Principles

The modern understanding of the rule of law encompasses several interrelated principles. Laws must be prospective, open, clear, and stable—people must be able to know the law and arrange their affairs accordingly. Retrospective legislation is particularly objectionable and is presumptively unconstitutional. There must be independent and impartial courts with accessible procedures—the judiciary must be free from interference by the executive or legislature. Judicial independence is guaranteed by statute, including the Constitutional Reform Act 2005. The executive must be accountable to the law—government actions must be subject to judicial review, and ministers must comply with court orders. Fundamental rights must be protected from arbitrary interference—the state cannot invade personal liberty without legal authority. The principle of legality, established in cases such as R v Secretary of State for the Home Department, ex parte Simms (2000), requires that fundamental rights cannot be overridden by general or ambiguous words in legislation. This principle ensures that Parliament must use clear language if it intends to restrict fundamental rights.

The Rule of Law and Access to Justice

Access to justice is a vital component of the rule of law. The UNISON case established that the constitutional right of access to the courts is inherent in the rule of law and cannot be removed by executive action or by legislation unless clearly authorised. The Legal Aid, Sentencing and Punishment of Offenders Act 2012 reduced the availability of legal aid, raising concerns about whether access to justice is adequately protected. The courts have responded by emphasising that the rule of law requires meaningful access to legal remedies, not merely formal rights. In R (Daly) v Secretary of State for the Home Department (2001), the House of Lords held that the common law right of confidential communication with legal advisers is a fundamental right that can only be restricted by clear statutory words. The courts continue to develop the rule of law through their supervisory jurisdiction and their interpretation of legislation.

Relationship with Parliamentary Sovereignty

The relationship between the rule of law and parliamentary sovereignty is contested. Some scholars, following Sir John Laws, argue that the rule of law is a higher-order constitutional principle that limits parliamentary sovereignty. The Supreme Court’s decision in R (Jackson) v Attorney General (2005) left open the possibility that courts might decline to apply legislation that subverts fundamental constitutional principles, suggesting that the rule of law ultimately conditions the exercise of legislative power. Lord Hope in Jackson stated that the rule of law enforced by the courts is the ultimate controlling principle of the UK constitution. Lord Steyn suggested that the courts might not accept a statute that sought to abolish judicial review. This view, while not yet accepted as orthodox, reflects the growing recognition that even sovereign Parliaments must respect fundamental legal principles. The relationship between these two constitutional pillars continues to evolve as courts develop the common law constitution.