Kenneth Warner examines the ex turpi causa non oritur actio principle
The principle “ex turpi causa non oritur actio” (from a bad cause no action arises) may be raised as a defence to an action in tort in a situation where the plaintiff’s harm arises out of the course of his own criminal actions.
The principle may find to condone its origin in Everet v Williams [1725] 68 LJQB 549, in which a highwayman apparently filed a Bill in Equity for an account against his partner in crime.
It is clear on the case-law that the defence is restricted to the context of serious criminal wrongdoing. In a case of a relatively minor offence, ex turpi causa, finds no proper place. In current law the principle is often articulated as expressing a strong sentiment of public policy, and while in a negligence action such failures as those described above may bring about a reduction of damages for contributory negligence, they are not viewed as justifying defeat of the plaintiff’s action entirely, where the normal features of the tort are clearly made out. The
