(a) (1) There is a Secretary of Defense, who is the head of the Department of Defense, appointed from civilian life by the President, by and with the advice and consent of the Senate. (2) A person may not be appointed as Secretary of Defense- (A) within seven years after relief from active duty as a commissioned officer of a regular component of an armed force in a grade below O-7; or (B) within 10 years after relief from active duty as a commissioned officer of a regular component of an armed force
5 U.S.C. § 5532 Pub. L. 106-65, div. A, title VI, §651(a)(1), Oct. 5, 1999, 113 Stat. 664] Section, Pub. L. 89-554, Sept. 6, 1966, 80 Stat. 482; Pub. L. 95-454, title III, §308(a), (c)-(f) (1), Oct. 13, 1978, 92 Stat. 1149-1151; Pub. L. 97-276, §151(b), Oct. 2, 1982, 96 Stat. 1200; Pub. L. 98-396, title III, §306, Aug. 22, 1984, 98 Stat. 1424; Pub. L. 98-525, title XV, §1537(b), Oct. 19, 1984, 98 Stat. 2635; Pub. L. 99-88, title I, §100, Aug. 15, 1985, 99 Stat. 351; Pub. L. 99-500, §101(l), Oct.