No regular enlisted member of an armed force may be discharged before his term of service expires, except—

1. (1) as prescribed by the Secretary concerned;
2. (2) by sentence of a general or special court martial; or
3. (3) as otherwise provided by law.

(Added Pub. L. 90–235, § 3(a)(1)(A), Jan. 2, 1968, 81 Stat. 757.)