The Rule of Law

Dicey's Traditional Definition

The rule of law is one of the foundational principles of the UK constitution. It requires that state power be exercised within legal limits, that all persons are equal before the law, and that constitutional principles are developed through the decisions of the courts. The concept was given its classical formulation by A.V. Dicey in his Introduction to the Study of the Law of the Constitution (1885), in which he identified three distinct limbs.

The First Limb: Legal Certainty, Personal Liberty, and Due Process

Dicey's first limb holds that no person should be punished or made to suffer in body or goods except for a distinct breach of law, established in the ordinary legal manner before the ordinary courts of the land. This encompasses three related sub-elements.

Legal certainty requires that there be no arbitrary exercise of power by the state. Government must act according to established law, and citizens must be able to predict the legal consequences of their actions. The principle received its most celebrated judicial expression in Entick v Carrington [1765], where the King's messengers entered Entick's home and seized his papers under a general warrant issued by the Secretary of State. The Court of Common Pleas held the warrant unlawful on the ground that there was no legal authority for such action. The state cannot interfere with individuals' rights without clear legal justification, and any such interference must be traceable to a specific rule of law.

Personal liberty requires that citizens should be detained or punished only if they have broken the law. The corollary is that citizens who have committed no wrong should be free from interference by the executive.

Due process of law requires that citizens have a right to fair procedures for determining civil or criminal liability. The right to a fair trial — encompassing impartial adjudication, the opportunity to be heard, and the right to know the case against one — is integral to this sub-element. Article 7 European Convention on Human Rights, incorporated into domestic law by the Human Rights Act 1998, reinforces this by prohibiting retrospective criminal penalties.

The Second Limb: Equality Before the Law

Dicey's second limb holds that every person, regardless of rank or condition, is subject to the ordinary law and amenable to the jurisdiction of the ordinary courts. This too encompasses three distinct sub-elements.

Like cases should be treated in like ways. There should be no unjustified discrimination between persons in the application of the law.

State officials have no exemption from legal control or accountability by reason of their position. Government ministers, civil servants and other public officers are equally subject to the law as private individuals. This principle was powerfully vindicated in M v Home Office [1994], where the House of Lords held that the Home Secretary was in contempt of court for breaching a court order requiring the return of an asylum seeker. The case confirmed unequivocally that ministers of the Crown are not above the law and are subject to the coercive jurisdiction of the courts, including proceedings for contempt.

Members of the executive should not legislate or adjudicate in court cases. This sub-element anticipates the modern principle of separation of powers: those who make and enforce law should not also be the judges of it.

It should be noted that Dicey's second limb has been criticised as overstating the position. In practice, the state does enjoy certain procedural advantages — for example, different limitation periods may apply in some contexts — so the notion of complete equality between citizen and state is something of an idealisation.

The Third Limb: Constitutional Principles Developed Through Judicial Decisions

Dicey's third limb holds that the general principles of the constitution — such as the right to personal liberty or freedom of assembly — are with us as the result of judicial decisions. Unlike many written constitutions, the UK has no single codified document setting out fundamental rights. Instead, the courts, as protectors of individual liberty, must develop constitutional principles through ordinary judicial decisions in the course of resolving concrete disputes. Rights in the UK are residual: one may do anything that is not prohibited by law, and the role of the courts is to identify and enforce the limits on state power. This stands in contrast to countries such as France or the United States, where a codified constitution is the primary source of fundamental rights.

The Rule of Law as a Constitutional Foundation

Beyond Dicey's three limbs, the rule of law performs a range of broader constitutional functions in the UK system.

Prevention of Arbitrary Power

The rule of law requires that government action be grounded in law and not in the unchecked will of officials. Where no legal authority exists for an act of the executive, that act is unlawful. Entick v Carrington [1765] remains the locus classicus of this principle. Similarly, in CCSU v Minister for Civil Service [1984], the House of Lords confirmed that the exercise of prerogative powers is in principle subject to judicial review, establishing that government decisions made under the Royal Prerogative are not immune from judicial scrutiny provided they are justiciable.

Governmental Accountability Through Judicial Review

Judicial review is the mechanism by which the courts hold the executive to account for the lawfulness of its decisions. It ensures that public bodies exercise their powers within the scope of what Parliament has authorised (the principle of ultra vires) and in accordance with procedural fairness. The decision in M v Home Office [1994] is a striking illustration of the courts' willingness to hold even senior ministers accountable.

Clarity of Law and the Prohibition on Retrospective Legislation

For the rule of law to be meaningful, citizens must be able to know and understand the law that governs them. Law must be set out clearly and must not operate retrospectively. Retrospective criminal legislation is considered particularly objectionable because it punishes conduct that was lawful when it was performed. The prohibition on retrospective criminal penalties is now reinforced by Article 7 European Convention on Human Rights, as given effect by the Human Rights Act 1998.

Equality Before the Law and Access to Justice

All citizens must be equal before the law, and the government or state must not enjoy special exemptions. Moreover, citizens must have a means of legal redress for their grievances. This requires not only formal equality but effective access to courts. In R (UNISON) v Lord Chancellor [2017], the Supreme Court unanimously held that the Employment Tribunals and Employment Appeal Tribunal Fees Order 2013 was unlawful because it prevented workers from bringing claims, thereby impeding access to justice. The Court confirmed that the right of access to courts is a constitutional right at common law and that Parliament does not legislate in a vacuum without regard to the rule of law. Critics have argued that the cuts to civil legal aid introduced by the Legal Aid, Sentencing and Punishment of Offenders Act 2012 have similarly impaired effective access to justice for those with limited financial means.

Independence of the Judiciary

The rule of law requires that the judiciary be independent of both the legislature and the executive. Without judicial independence, the courts cannot reliably hold the government to account or protect individuals' rights. The Constitutional Reform Act 2005 made significant structural changes to reinforce this independence. It established the Supreme Court of the United Kingdom as a new, independent final court of appeal, replacing the Appellate Committee of the House of Lords with effect from October 2009. It also reformed the office of Lord Chancellor, transferring that office's judicial functions to the Lord Chief Justice, thereby separating the role of the head of the judiciary from the executive and legislative branches. These reforms strengthened the separation of powers and gave institutional expression to the rule of law.

Modern Interpretation: Lord Bingham's Eight Elements

The most influential modern reformulation of the rule of law is that of Lord Bingham in his book The Rule of Law (2010). Lord Bingham identified eight elements, which together provide a more detailed and nuanced account than Dicey's three limbs:

1. The law must be accessible, intelligible, clear and predictable.
2. Questions of legal right and liability should ordinarily be resolved by the application of the law, not the exercise of discretion.
3. Laws should apply equally to all, save to the extent that objective differences justify differentiation.
4. Ministers and public officers at all levels must exercise the powers conferred on them in good faith, fairly, for the purpose for which the powers were conferred, without exceeding the limits of such powers and not unreasonably.
5. The law must afford adequate protection of fundamental human rights.
6. Means must be provided for resolving, without prohibitive cost or inordinate delay, bona fide civil disputes which the parties themselves are unable to resolve.
7. Adjudicative procedures provided by the state should be fair.
8. The state must comply with its obligations in international law as in national law.

Lord Bingham's formulation is significant in a number of respects. Elements 5 and 8 extend the rule of law beyond a purely domestic and formal conception to encompass substantive human rights protections and international legal obligations. Element 2 addresses the dangers of excessive executive discretion, whilst element 3 reflects Dicey's equality limb in a more qualified and realistic form. Taken together, the eight elements provide law students with a practical framework for analysing whether a given government measure is consistent with the rule of law.

The JUSTICE Manifesto

JUSTICE, the British legal reform organisation, has also produced a Manifesto for the Rule of Law that identifies seven principles regarded as essential to its maintenance in the United Kingdom. These draw on both domestic and international human rights standards:

1. The UK should adhere to international human rights standards, both domestically and in foreign policy, and human rights should be constitutionally protected.
2. The independence of the legal profession and the judiciary must be upheld; the government should refrain from criticising the judiciary.
3. Due process and the right to a fair trial must be protected.
4. There should be equality before and under the law, with no discrimination.
5. There should be an equal right of access to justice; no one should be deprived of this right by reason of financial or other disadvantage.
6. Parliament should have greater powers to scrutinise legislation and hold ministers to account; the scope of the Royal Prerogative should be restricted.
7. Greater co-operation between EU member states must be accompanied by greater protection for the rights of individuals. (Note: while this point predates the United Kingdom's withdrawal from the European Union, the underlying concern — that integration should not come at the expense of individual rights — retains relevance in debates about international co-operation more broadly.)

Point 4 is particularly noteworthy as a discrete requirement of equality, distinct from mere formal equality before the courts. Point 5 echoes the concern raised in R (UNISON) v Lord Chancellor [2017] regarding access to justice, and point 6 reflects ongoing debates about the accountability of ministers exercising prerogative powers — a matter addressed by the Supreme Court in R (Miller and another) v Secretary of State for Exiting the European Union [2017].

The rule of law is not a single, fixed rule but a cluster of related principles that together constrain the exercise of public power and protect individuals from arbitrary treatment. From Dicey's nineteenth-century formulation to Lord Bingham's modern eight elements and the JUSTICE Manifesto, successive thinkers have refined and expanded the concept to meet contemporary challenges. In the UK's uncodified constitutional system, the rule of law performs an especially vital function: in the absence of a supreme written constitution against which legislation can be struck down, the principle that government must act within the law — enforceable through the courts — provides a critical safeguard for civil liberties and democratic governance. Cases such as Entick v Carrington [1765], M v Home Office [1994] and R (UNISON) v Lord Chancellor [2017] demonstrate that the courts remain willing to hold the state to account under this principle, even in politically sensitive contexts.