Ex turpi causa non oritur actio
|Part of the common law series|
|Liability and remedies|
|Duty to visitors|
|Other common law areas|
Ex turpi causa non oritur actio (Latin for "from a dishonorable cause an action does not arise") is a legal doctrine which states that a plaintiff will be unable to pursue legal remedy if it arises in connection with his own illegal act. Particularly relevant in the law of contract, tort and trusts, ex turpi causa is also known as the "illegality defence", since a defendant may plead that even though, for instance, he broke a contract, conducted himself negligently or broke an equitable duty, nevertheless a claimant by reason of his own illegality cannot sue.
|“||The objection, that a contract is immoral or illegal as between plaintiff and defendant, sounds at all times very ill in the mouth of the defendant. It is not for his sake, however, that the objection is ever allowed; but it is founded in general principles of policy, which the defendant has the advantage of, contrary to the real justice, as between him and the plaintiff, by accident, if I may say so. 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. If, from the plaintiff's own standing or otherwise, the cause of action appears to arise ex turpi causa, or the transgression of a positive law of this country, there the court says he has no right to be assisted. It is upon that ground the court goes; not for the sake of the defendant, but because they will not lend their aid to such a plaintiff. So if the plaintiff and defendant were to change sides, and the defendant was to bring his action against the plaintiff, the latter would then have the advantage of it; for where both were equally in fault, potior est conditio defendentis.||”|
|“||If two burglars, A and B, agree to open a safe by means of explosives, and A so negligently handles the explosive charge as to injure B, B might find some difficulty in maintaining an action for negligence against A.||”|
It is not absolute in effect. For example, in Revill v Newbery an elderly allotment holder was sleeping in his shed with a shotgun, to deter burglars. On hearing the plaintiff trying to break in, he shot his gun through a hole in the shed, injuring the plaintiff. At first instance, the judge awarded damages on the basis that the defendant had used violence in excess of the reasonable limits allowed by lawful self defence and was negligent to the standard of care expected of a reasonable man who found himself in such a situation. On appeal the defendant raised the defence of 'ex turpi causa', but the Court of Appeal held that while public interest required that someone should not benefit from his illegal conduct, different considerations applied in cases arising in tort as opposed to those in a property or contract context. Old common law authorities and the Law Commission report (Liability for Damage or Injury to Trespassers) acknowledged the existence of some duty towards trespassers and the defendant could not rely on the doctrine to relieve himself of liability.
The precise scope of the doctrine is not certain. In some cases, it seems that the illegality prevents a duty of care arising in the first place. For example, in Ashton v Turner the defendant injured the plaintiff by crashing their car in the course of fleeing the scene of a burglary they had committed together. Ewbank J held that the court may not recognise a duty of care in such cases as a matter of public policy. Similarly, in Pitts v Hunt the Court of Appeal rationalised this approach, saying that it was impossible to decide the appropriate standard of care in cases where the parties were involved in illegality.
In other cases, the courts view ex turpi as a defence where otherwise a claim would lie, again on grounds of public policy. In Tinsley v Milligan Nicholls LJ in the Court of Appeal spoke of the court having to "weigh or balance the adverse consequences of granting relief against the adverse consequences of refusing relief". The plaintiff was ultimately successful in Tinsley v Milligan in the House of Lords, which allowed the claim on the grounds that the plaintiff did not need to rely on the illegality.
|This section requires expansion. (December 2010)|
- Winfield & Jolowicz on Tort, 15th edition, 866, suggest that the doctrine should be purely confined to contract
- (1775) 1 Cowp 341, 343
-  AC 403
-  1 All ER 291
-  QB 137
-  3 All ER 344
-  Ch 310
-  3 WLR 167