What is judicial review?
The nutshell
Judicial review is a kind of court case. A judge checks whether a public body, such as the government or a council, followed the law when it made a decision.
Every fact on this page comes from official court guidance and non-partisan explainers. Each source tag — like HoC — opens where a fact comes from.
The basics
What judicial review is
Judicial review is a kind of court case. A judge looks at a decision made by a public body, such as the government, a minister, a council or a regulator, and checks whether the law was followed.HoC Judicial review is not about whether the decision was a good one. It is only about whether the decision was made in a lawful way.Jud
What a judge can look at
A judge can overturn a decision for three main reasons, the Institute for Government explains. The first is illegality, when the public body had no legal power to act. The second is procedural unfairness, when the way the decision was made was unfair. The third is irrationality, when a decision is so unreasonable that no reasonable person could have made it.IfG
Which court hears the case
Most judicial reviews in England and Wales are heard by the Administrative Court. It is a specialist part of the High Court.GOV A claim must usually be brought quickly, within three months of the decision, the House of Commons Library notes.HoC
What happens if a claim wins
If a judicial review succeeds, a court can quash the decision, which means the decision is cancelled.IfG Often the public body then has to make the decision again. A win does not always change the final answer, because the public body may reach the same decision in a lawful way.
- Judicial review checks how a decision was made, not whether it was the right decision, according to the House of Commons Library
- A public body can be a minister, a government department, a council or a regulator, the Institute for Government explains
- If a claim succeeds, a court can quash the decision, which often means the public body has to make it again, the Institute for Government says
- Judicial review is not an appeal, so a judge does not replace a decision just because a judge would have chosen differently, the Institute for Government notes
- Winning does not always change the final outcome, because the public body may reach the same decision again in a lawful way
- Most claims never reach a full hearing, because a court must first agree the case is arguable, the Institute for Government reports
The deep end6 min
The court case, in full
Judicial review is a court process in which a claimant challenges the lawfulness of a decision, action or failure to act by a public body carrying out a public function, according to the Institute for Government.IfG It is not an appeal. A judge does not swap in a preferred decision, and cannot overturn a decision merely because a different decision might have been made.IfG The Courts and Tribunals Judiciary states that judicial review challenges the lawfulness of a decision, including the procedures by which it was reached, rather than the substantive merits.Jud
The three grounds
The Institute for Government sets out three main grounds. Illegality covers a decision made without the legal power to make it. Procedural unfairness covers a decision reached in an unfair way, such as bias or a failure to hear from those affected. Irrationality covers a decision so unreasonable that no reasonable person, acting reasonably, could have made it. This is a very high bar, and courts rarely find it is met.IfG
The court, and the time limit
In England and Wales, judicial review claims are heard by the Administrative Court, a specialist court within the King's Bench Division of the High Court, according to GOV.UK.GOV The court sits in London and also in Birmingham, Cardiff, Leeds and Manchester. A claim must be brought promptly, and within three months of the decision being challenged, the House of Commons Library records.HoC
What a court can order
If a claim succeeds, the court chooses a remedy. The House of Commons Library lists a quashing order to undo a decision, a mandatory order to make a public body act, a prohibiting order to stop an unlawful action, an injunction, and a declaration stating the legal position.HoC A quashed decision often has to be taken again, so a claimant who wins may still not get a different final outcome.IfG