Judicial Review in the United Kingdom

Introduction

Judicial review is the primary mechanism by which the High Court supervises the exercise of public functions to ensure legality, rationality, and procedural fairness. Unlike an appeal, judicial review does not examine the merits of a decision but rather the lawfulness of the decision-making process. The procedure is governed by the Senior Courts Act 1981, section 31, and the Civil Procedure Rules Part 54. Judicial review is a remedy of last resort, available only where there is no adequate alternative statutory right of appeal or review.

The Permission Stage

A significant procedural filter in UK judicial review is the permission stage, formerly known as leave. Under CPR 54.4, no claim for judicial review may proceed without the permission of the court. The claimant must file a claim form promptly and in any event within three months of the grounds giving rise to the claim. The purpose of the permission stage is to weed out hopeless, frivolous, or abusive claims at an early stage, thereby protecting public bodies from wasteful litigation and conserving judicial resources.

At the permission stage, the judge considers the claim on paper and determines whether it is arguable — that is, whether it discloses a serious issue to be tried. If permission is refused, the claimant may request an oral hearing to renew the application. In certain types of claim, such as planning challenges and procurement decisions, the court may apply a more stringent test, requiring the claimant to show a highly arguable case. The permission stage has been criticised for imposing a disproportionate burden on litigants, particularly in claims concerning fundamental rights, and the Law Commission has recommended reforms to improve transparency and efficiency.

Ground One: Illegality

Illegality is the first ground of review identified by Lord Diplock in Council of Civil Service Unions v Minister for the Civil Service (1985), the GCHQ case. A decision is illegal when the decision-maker exceeds the legal authority conferred by Parliament or misdirects itself in law. Illegality encompasses several sub-categories.

Error of law occurs when a decision-maker misunderstands or misapplies the legal framework governing its powers. Following Anisminic Ltd v Foreign Compensation Commission (1969), any error of law by a public body renders the decision a nullity, collapsing the traditional distinction between jurisdictional and non-jurisdictional errors. Error of fact may also ground review where the decision-maker proceeds on the basis of a mistaken finding of fact that is fundamental to the decision.

Fettering of discretion arises when a decision-maker rigidly applies a policy without considering whether individual circumstances justify a departure from that policy. A public body may adopt policies to guide its decision-making, but it must remain open to considering the merits of each case. Improper purpose occurs when a decision-maker exercises a power for a purpose other than that for which the power was conferred, as in Padfield v Minister of Agriculture (1968), where the minister’s refusal to appoint a committee of investigation frustrated the policy of the statute.

Relevant and irrelevant considerations require that the decision-maker take into account all matters that the statute requires to be considered and disregard matters that are legally irrelevant. The weight to be given to relevant considerations is generally a matter for the decision-maker, unless the weight given is so unreasonable as to amount to an error of law.

Ground Two: Irrationality

Irrationality, also known as Wednesbury unreasonableness, derives from Associated Provincial Picture Houses v Wednesbury Corporation (1948). Lord Greene MR held that a decision is unreasonable only if it is “so unreasonable that no reasonable authority could ever have come to it.” This sets a high threshold, reflecting judicial deference to administrative discretion in matters of policy and judgment.

The intensity of Wednesbury review varies with context. In cases affecting fundamental rights, the court applies anxious scrutiny, requiring a more rigorous examination of the justifications for the decision, as established in R v Secretary of State for the Home Department, ex parte Bugdaycay (1987). Lord Bridge stated that “the most fundamental of all human rights” require the court to subject administrative decisions to “the most rigorous scrutiny.” The relationship between Wednesbury and proportionality remains contested, with the Supreme Court in Pham v Secretary of State for the Home Department (2015) leaving open the question of whether proportionality has supplanted Wednesbury for common law rights.

Ground Three: Procedural Impropriety

Procedural impropriety encompasses two distinct principles: the common law duty to act fairly and failures to comply with statutory procedural requirements.

The rule against bias requires that decision-makers be impartial. The test, established in Porter v Magill (2002), is whether a fair-minded and informed observer, having considered the facts, would conclude that there was a real possibility of bias. This objective test applies to both direct interest bias (where the decision-maker has a personal interest in the outcome) and apparent bias (where the circumstances give rise to a perception of partiality).

The right to a fair hearing requires that affected persons be given adequate notice of the case against them and a meaningful opportunity to respond. The content of the duty varies according to the context, including the nature of the decision, the statutory framework, and the importance of the decision to the affected individual. In Ridge v Baldwin (1964), the House of Lords held that a chief constable dismissed without being given an opportunity to defend himself was entitled to have the dismissal quashed for breach of natural justice.

Conclusion

Judicial review in the United Kingdom provides a constitutional mechanism for holding public bodies to account, enforcing the rule of law, and protecting individuals from the abuse of executive power. The three grounds of review — illegality, irrationality, and procedural impropriety — provide the doctrinal framework, while the permission stage serves as a gatekeeping mechanism to filter unmeritorious claims. The development of proportionality and the influence of the Human Rights Act 1998 continue to reshape the landscape of UK judicial review, ensuring that the common law adapts to contemporary constitutional demands.