10 U.S.C. § 7320: More than thirty years: permanent professors and the Director of Admissions of the United States Military Academy

(a) The Secretary of the Army may retire an officer specified in subsection (b) who has more than 30 years of service as a commissioned officer. (b) Subsection (a) applies in the case of the following officers:(1) Any permanent professor of the United States Military Academy. (2) The Director of Admissions of the United States Military Academy.