justae nuptiae (j[schwa]s-tee n[schwa]p-shee-ee). [Latin “legal marriage”] Roman law. A marriage between two persons who had the legal capacity to wed. • Justae nuptiae was the only union that created the familial relationship known as patria potestas.

— Also termed justum matrimonium. See patria potestas under POTESTAS. Cf. CONCUBINATUS.

“Iustae nuptiae is such a marriage as satisfies all the rules of civil law. Any marriage between two persons who had the capacity of civil marriage with each other (conubium) was necessarily iustae nuptiae, for if the union was defective in any other respect it was no marriage at all. On the other hand, if there was no conubium between the parties it might still be actually a marriage (nuptiae, nuptiae non iustae), the wife being uxor non iusta, the children liberi non iusti. Such a marriage, in which one party at least would not be a civis, did not produce patria potestas over children ….” W.W. Buckland, A Manual of Roman Private Law 63–64 (2d ed. 1953).