No action or proceeding shall be prosecuted or maintained against a member of a military court or officer or person acting under its authority or reviewing its proceedings on account of the approval of imposition or execution of any sentence, warrant, writ process or mandate of any military court, nor shall any officer or enlisted man be liable to a civil action or criminal prosecution for any act done while in the discharge of his military duty when such act is in the line of duty.
S.C. Code § 25-1-2170