VOLENTI NON FIT INJURIA. A maxim meaning literally : No one can enforce a right arising out of a transaction which he has voluntarily assented to. It applies to in tentional acts which would otherwise be tor tious ; consent, for example, to an entry on land which would otherwise be a trespass, or consent to a physical harm which would otherwise be an assault, as in the case 'of a boxing match or a surgical operation. How ever, such consent does not exclude criminal liability. No person can lawfully consent to his own death, so that killing• a man in a duel is murder. Nor can one lawfully con sent to grievous bodily harm, save for some reasonable purpose ; for example, a proper surgical operation ; 8 Q. B. D. 534.
A master is under a •legal duty to his serv ant to take care' that the premises, plant, and machinery are reasonably safe; but where the servant expressly or irupliedly agrees to exempt his master from this obligation, in whole or in part and to take the risk upon himself, the maxim applies; [1891] A. C. 325.
Mere knowledge of an impending wrongful act or of the existence of a wrongfully caused danger does not of itself affiount to' consent, even though no attempt is' made by the plain tiff to prevent or avoid the act or danger. Kmiwledge may, however, be evidence of con sent-; [1891] A. C. 325 ; and even if it does not prove an agreement to take the risk, it may nevertheless be a bar to the plaintiff's action, in that it may negative the existence of any negligence on the part of the defend ant in causing the danger, or it may estab lish the existence of contributory negligence on the part of the plaintiff.
See CONSENT; CRIME; ASSAULT; MASTER AND SERVANT.