Legal Definitions - pari causa, in

Definition: In a case affecting two parties equally or in which they have equal rights.

Example: In a dispute over property ownership, if both parties have equal evidence to support their claim, the possessor (the one currently in possession of the property) will usually win the case. This is because they have equal rights in the matter, and in pari causa, the possessor typically defeats the nonpossessory claimant.

This legal term means that when two parties have equal rights or claims in a matter, the one who is currently in possession of the property or object in question will usually win the case. This is because they have an equal footing in the dispute, and the law tends to favor the person who is already in possession of the item.