Jean Garin, Guarin, and also spelled Guerin, in Latin written both Garini and Guerini, was a descendant of an ancient law family.

Doctor of law in 1415, dean of the Faculty of Law from January, 1419, to November 1422, named by Henry VI to a canonial prebend in the church at Rouen, he was, in 1423 and 1430, a deputy to the Estates of Normandy. He was in charge of installing the library of the Chapter at Rouen.

Jean Garin exercised the functions of treasurer of the archbishopric from 1429, and he is described also as archdeacon of Veulguessin le François. He died at Bâle in 1433

Naturally the opinion of this lawyer conformed to the opinion of the Faculty of Law. In the final sentence Jean Garin followed the opinion of the Abbot of Fécamp, Gilles de Duremort.