Holman v Johnson (1775) 1 Cowp 341. Lord Mansfield: ''The principle of public policy is this: ex dolo malo non oritur actio. No court will lend its aid to a man who founds his cause of action upon an immoral or an illegal act.'' The foundational statement of the doctrine; the maxim ex turpi causa non oritur actio (no action arises from a base cause).
St John Shipping Corp v Joseph Rank Ltd [1957] 1 QB 267. The master overloaded the ship in breach of the Merchant Shipping Acts; the shipowner sued for freight. Devlin J held that the freight was recoverable: the statute was directed at the master''s conduct, not at the underlying contract of carriage. The case is the leading authority on the statutory-construction approach to illegality.
Tinsley v Milligan [1994] 1 AC 340. Two women had purchased a house in joint names but registered it in one name only, to enable the other to claim social security benefits illegally. The House of Lords held by 3-2 that the woman whose name was not on the register could establish a beneficial interest in the property by reference to her contributions, without relying on the illegal arrangement. The reliance test (Lord Browne-Wilkinson) was that a claimant could recover if the claim could be established without relying on the illegality.
Patel v Mirza [2016] UKSC 42. The claimant had paid £620,000 to the defendant for the purpose of betting on Royal Bank of Scotland shares using insider information; the betting did not take place; the claimant sought return of the money. The Supreme Court (by 9 to 0 on the result; 6 to 3 on reasoning) held that the claimant was entitled to restitution. Lord Toulson articulated the policy-based test: (a) the underlying purpose of the prohibition; (b) other relevant public policy; (c) proportionality, having regard to seriousness, centrality, intentionality, and disparity of culpability. The decision overruled Tinsley v Milligan on the reliance test.
Henderson v Dorset Healthcare University NHS Foundation Trust [2020] UKSC 43. The claimant had killed her mother during a psychotic episode; she had been convicted of manslaughter on the ground of diminished responsibility; she sued the NHS trust for negligence in failing to detain her. The Supreme Court held that the claim was barred by ex turpi causa: the Patel v Mirza test applied, but the seriousness and centrality of the killing made denial of the claim a proportionate response. The case shows that Patel v Mirza does not always result in claimant recovery; the policy analysis can support denial.
Stoffel & Co v Grondona [2020] UKSC 42. The defendant had engaged in mortgage fraud; the claimant solicitors had failed to register the discharge of an existing mortgage, exposing the defendant to liability. The defendant counterclaimed against the solicitors for negligence. The Supreme Court held that the Patel v Mirza test favoured allowing the counterclaim: the underlying mortgage fraud was serious but not central to the negligence claim; denying the claim would not advance the public interest in deterring mortgage fraud. The case clarifies the application of Patel v Mirza in commercial contexts.
Esso Petroleum v Harper''s Garage (Stourport) Ltd [1968] AC 269. The leading modern authority on solus agreements and the restraint-of-trade doctrine. The House of Lords held that the 21-year solus tie was unreasonable but the 4-year tie was reasonable. The case applies the Nordenfelt test to commercial supply agreements.
Schroeder Music Publishing Co Ltd v Macaulay [1974] 1 WLR 1308. The House of Lords held that a 5-year exclusive songwriting contract was unreasonable as a restraint of trade. Lord Reid emphasised the inequality of bargaining power between the songwriter and the publisher. The case extends restraint-of-trade analysis into employment-style contracts where one party has substantially greater bargaining power.