32 CFR § 53.2 - Policy.
(a) Members of the Armed Forces (including retired members and members of reserve components). The wearing of the uniform is prohibited under any of the following circumstances:
(1) At any meeting or demonstration which is a function of, or sponsored by an organization, association, movement, group, or combination of persons which the Attorney General of the United States has designated, pursuant to E.O. 10450 as amended, as totalitarian, fascist, communist, or subversive, or as having adopted a policy of advocating or approving the commission of acts of force or violence to deny others their rights under The Constitution of the United States, or as seeking to alter the form of Government of the United States by unconstitutional means.
(2) During or in connection with the furtherance of political activities, private employment or commercial interests, when an inference of official sponsorship for the activity or interest could be drawn.
(3) Except when authorized by competent Service authority, when participating in activities such as public speeches, interviews, picket lines, marches, rallies or any public demonstrations (including those pertaining to civil rights), which may imply Service Sanction of the cause for which the demonstration or activity is conducted.
(4) When wearing of the uniform would tend to bring discredit upon the Armed Forces.
(5) When specifically prohibited by regulations of the department concerned.
(b) Former members of the Armed Forces.
(1) Unless qualified under another provision of this part or under the provisions of 10 U.S.C. 772, former members who served honorably during a declared or undeclared war and whose most recent service was terminated under honorable conditions may wear the uniform in the highest grade held during such war service only upon the following occasions and in the course of travel incidents thereto:
(i) Military funerals, memorial services, weddings, and inaugurals.
(ii) Parades on national or State holidays; or other parades or ceremonies of a patriotic character in which any active or reserve U.S. military unit is taking part.
(2) Wearing of the uniform or any part thereof at any other time or for any other purpose is prohibited.
(c) Medal of Honor holders. Persons who have been awarded the Medal of Honor may wear the uniform at their pleasure except under the circumstances set forth in paragraph (a) of this section.