Latin. Of one's own right. Of full capacity. One who has all the rights to which a freemen is entitled; one who is not under the power of another, as a slave, a minor, and the like. To make a valid contract, a person must, in general, be sui juris. Every one of full age is presumed to be sui juris.
Persons who are independent of the control of others as regards their legal acts, and who can validly contract, and bind themselves by legal obligation without the consent of another, are called sui juris; that is, they can contract, &c., as of their own right. See Alieni juris.