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England & Wales • CPR Part 54 • Administrative Court

Judicial Review Guide 2026

A practical public-law guide to challenging unlawful decisions, actions and failures by public bodies, including grounds, standing, alternative remedies, time limits, pre-action procedure, permission and court remedies.

Nature of Judicial Review

Review of Lawfulness, Not a General Appeal

Judicial review is a public-law procedure through which the court supervises the lawfulness of decisions, actions or failures to act by public bodies or bodies exercising public functions.

The court will normally not substitute its own decision for that of the public authority simply because it would have reached a different conclusion. A successful claim can result in public-law relief and, where appropriate, a requirement for the decision-maker to reconsider the matter lawfully.

Procedural Framework

Main forumAdministrative Court
RulesCPR Part 54
Default deadlinePromptly / max 3 months
PermissionRequired
Pre-actionProtocol normally applies

Judicial Review Issue-Spotting Tool

Public-Law Issue Evaluator

Select the likely forum, ground and whether another remedy may be available.

Main Judicial Review Grounds

GroundTypical public-law problemLeading authority
Illegality / Error of LawThe decision-maker misunderstood or exceeded the legal powers or duties applicable to the decision, applied the wrong legal test, acted for an improper purpose, or otherwise acted unlawfully.Council of Civil Service Unions v Minister for the Civil Service [1985] AC 374
Irrationality / Wednesbury UnreasonablenessA decision may be unlawful where it falls outside the range of decisions reasonably open to the decision-maker. The court does not merely substitute its own preferred view on the merits.Associated Provincial Picture Houses Ltd v Wednesbury Corporation [1948] 1 KB 223
Procedural Impropriety / Procedural UnfairnessPossible grounds include failure to follow mandatory statutory procedure, denial of a fair hearing, failure to comply with applicable procedural duties, or apparent bias applying the fair-minded and informed observer test where relevant.Ridge v Baldwin [1964] AC 40; Porter v Magill [2001] UKHL 67
Legitimate ExpectationA public authority may be required to respect a sufficiently clear and legally relevant expectation arising from a representation or established practice, subject to the facts, the legal framework and the public-interest balance.R v North and East Devon Health Authority, ex p Coughlan [2001] QB 213

Before Filing: Standing, Alternative Remedy and Forum

Sufficient Interest

A claimant generally needs sufficient interest in the matter under section 31(3) of the Senior Courts Act 1981. Standing is assessed by the court and can become an issue at permission or later.

Alternative Remedy

If there is an adequate appeal, statutory review or other effective remedy, judicial review may be inappropriate or unavailable. The correct route depends on the legal scheme.

Correct Defendant / Forum

The identity of the decision-maker and the type of decision determine the correct respondent, interested parties and court or tribunal.

Time Limits and Pre-Action Procedure

RuleCurrent position
Default CPR 54.5 deadlineFile promptly and in any event within 3 months after the grounds first arose.
Certain planning cases6 weeks under CPR 54.5(5).
Certain procurement casesA shorter statutory period may apply; specified procurement challenges can have a 30-day period.
Pre-Action ProtocolA letter before claim and normally 14-day response period, where appropriate.

Judicial Review Remedies

RemedyTypical function
Quashing OrderSets aside an unlawful decision. Since the Judicial Review and Courts Act 2022, the court can in appropriate cases suspend the order or limit its retrospective effect.
Mandatory OrderRequires a public body to perform a public-law duty.
Prohibiting OrderPrevents a body or tribunal from acting unlawfully in a matter within the scope of the remedy.
DeclarationStates the legal position or rights without necessarily compelling a specific act.
InjunctionMay restrain or require conduct where the legal conditions for an injunction are satisfied, including urgent interim relief in appropriate cases.
Damages / Restitution / Recovery of SumCan be included in a judicial-review claim where legally available, but these cannot generally be sought as the sole remedy under the CPR Part 54 procedure.

Immigration and Tribunal Judicial Review

Immigration and asylum judicial review requires particular care because the correct forum is not always the Administrative Court. GOV.UK states that the Upper Tribunal Immigration and Asylum Chamber has jurisdiction for judicial review of most immigration decisions within its jurisdiction, while some cases require an appeal or an Administrative Court claim instead.

Frequently Asked Questions (6)

Judicial review is a public-law procedure in which a court reviews the lawfulness of a decision, action or failure to act by a public body or other body exercising a public-law function. It is primarily concerned with lawfulness rather than whether the judge would have made the same decision on the merits. The court can provide public-law remedies where the legal requirements are met.

The classic GCHQ categories identified by Lord Diplock are illegality, irrationality and procedural impropriety. Modern public law also recognises other grounds and doctrines, including error of law, legitimate expectation, proportionality where applicable, human-rights arguments and failures to comply with statutory public duties. The correct ground depends on the facts, legal framework and decision being challenged.

Under CPR 54.5, the claim form must be filed promptly and, in any event, no later than 3 months after the grounds for the claim first arose, unless another enactment or rule sets a shorter period. Certain planning judicial reviews have a 6-week period, while specified procurement challenges have shorter statutory periods. The time limit is not extended simply because the parties are following the Pre-Action Protocol.

Where the Pre-Action Protocol applies, the parties are normally expected to exchange a letter before claim and response before proceedings are issued. The defendant is normally given 14 days to respond. However, the protocol does not extend the court deadline, and in urgent cases the claimant may need to issue proceedings without waiting for the full response period.

Usually no. Judicial review is not normally an appeal on the merits. The court reviews legality and may quash a decision, prohibit unlawful future action, require performance of a public duty, make a declaration or grant an injunction where appropriate. A matter may then be remitted to the public authority for a lawful decision. A quashing order can now also be suspended or have its retrospective effect limited in appropriate cases.

Sometimes, but the correct forum and procedure depend on the decision. Some immigration and asylum judicial reviews are brought in the Upper Tribunal Immigration and Asylum Chamber, while other matters belong in the Administrative Court. Where there is a statutory appeal or another adequate remedy, judicial review may be inappropriate or unavailable. GOV.UK specifically advises checking whether an appeal, UTIAC judicial review or Administrative Court claim is the correct route.

Official Judicial Review Sources