32 CFR 765.13 – Insignia to be worn on uniform by persons not in the service
(a) Under title 10 U.S.C., section 773, members of military societies composed of persons discharged honorably or under honorable conditions from the United States Army, Navy, Air Force or Marine Corps, regular or reserve, may, when authorized by regulations prescribed by the President, wear the uniform duly prescribed by such societies to be worn by the members thereof.
(b) The law cited in paragraph (a) of this section further provides that instructors and members of duly organized cadet corps at certain institutions of learning may wear the uniform duly prescribed by the authorities of such institutions.
(c) The law cited in paragraph (a) of this section further provides that the uniform worn by members of the military societies or by members and instructors of the cadet corps referred to in paragraph (a) of this section shall include some distinctive mark or insignia prescribed by the Secretary of the military department concerned to distinguish such uniforms from the uniforms of the Army, Navy, Air Force, or Marine Corps.
(d) Accordingly, except as otherwise provided in this paragraph, the following mark is hereby designated to be worn by all persons wearing the Navy or Marine Corps uniform as provided in paragraphs (a), (b), and (c) of this section: A diamond, 3
(e) Within the meaning of paragraph (a) of this section, the occasions when members of the military societies may wear the uniform of their respective society are official functions which such a member attends in his capacity as a war veteran or as a member of such military society.
(f) Marine Corps Uniform Regulations may be examined and individual copies of pertinent provisions thereof may be purchased in accordance with § 701.1 of this chapter.