Public & constitutional
England & Wales
A public-law decision may be challenged on the grounds of illegality (the decision-maker misunderstood or exceeded its powers), irrationality (no reasonable decision-maker could have reached it), or procedural impropriety (failure to observe basic rules of fairness or statutory procedure). Proportionality applies where Convention or retained EU rights are engaged.
Appeal from the King's Bench Division dismissed; the cinema's challenge to the Sunday licensing condition failed.
Source of the irrationality standard, a decision so unreasonable that no reasonable authority could have made it.
What cuts the other wayWednesbury unreasonableness is now a low-intensity standard; where Convention rights are engaged, claimants must argue proportionality instead and Wednesbury offers little protection.
Appeal from the Court of Appeal allowed; the ouster clause did not bar judicial review of a determination vitiated by error of law.
Collapsed the jurisdictional and non-jurisdictional error distinction, virtually any error of law is reviewable.
What cuts the other wayPrivacy International [2019] UKSC 22 reaffirmed Anisminic, but Parliament continues to legislate against it (e.g. parts of the Judicial Review and Courts Act 2022); ouster clauses remain a live battleground.
Appeal from the Court of Appeal dismissed; national security justified the absence of consultation and the union's challenge failed.
Lord Diplock's tripartite classification of grounds (illegality, irrationality, procedural impropriety), the structural map of judicial review.
What cuts the other wayGCHQ recognised national security as a non-justiciable carve-out; the same reasoning is invoked to deny review of high-policy and prerogative decisions.
Appeal from the Court of Appeal allowed; the prison cell-search policy was held unlawful.
Recognised proportionality as a distinct, more intensive standard where Convention rights are engaged.
What cuts the other wayDaly applies a structured proportionality test only where Convention or EU rights are engaged; in pure common-law cases Wednesbury still controls and a claimant cannot demand proportionality review by default.
A local authority refused a licence without giving reasons or hearing the applicant. Build the strongest judicial review challenge.
LexCases will run the argument against current case law and rank the cases, including these foundations and any later cases that have built on or pulled away from them.
Curated for England & Wales. Always verify each case before relying on it in formal work. Citations are accurate at the time of publication, but the law moves.