Trover (Fr. Trouver To Find), the name of an action at law in common use in England and in the United States, to determine the ownership of property. The plaintiff declares, in substance, that he was lawfully possessed of a certain article on a certain day, and lost the same; that it came into the possession of the defendant by finding; and that the defendant has refused to deliver it to the plaintiff, and has converted it to his own use. This action is one form of trespass on the case. (See Trespass.) In the distant age when it was first used, the declaration may have narrated accurately the facts of the case; but for a long time the losing and finding have been regarded as mere legal fictions, which the defendant is not at liberty to deny. The action is maintainable: 1, where the property in question is a personal chattel; 2, where the plaintiff had a general or special property in the thing with a right of possession; 3, where the defendant has wrongfully converted the thing to his own use, which conversion may be proved by his wrongful taking of it, or his wrongful detention of it, or his wrongful use or misuse of it.

The action demands not the thing itself, but damages for the wrongful conversion; and if the plaintiff recovers, the damages should be measured by the value of the thing at the time of the conversion, with interest, and the judgment is for these damages and costs.