This is a pretty big deal. Key points after the DOD instruction.
3.1. The wearing of the uniform by members of the Armed Forces (including retired members and members of Reserve components) is prohibited under any of the following circumstances:
3.1.1. At any meeting or demonstration that is a function of, or sponsored by an organization, association, movement, group, or combination of persons that the Attorney General of the United States has designated, under Executive Order 10450 as amended (reference (c)), 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.
3.1.2. During or in connection with furthering political activities, private employment or commercial interests, when an inference of official sponsorship for the activity or interest may be drawn.
3.1.3. Except when authorized by the approval authorities in subparagraph 4.1.1., when participating in activities such as unofficial public speeches, interviews, picket lines, marches, rallies or any public demonstration, which may imply Service sanction of the cause for which the demonstration or activity is conducted.
3.1.4. When wearing of the uniform may tend to bring discredit upon the Armed Forces.
3.1.5. When specifically prohibited by regulations of the Department concerned.
(sections 3.2 and 3.3 address former members and Medal of Honor holders.)
- RESPONSIBILITIES
4.1. The Under Secretary of Defense for Personnel and Readiness and the Principal Deputy Under Secretary of Defense for Personnel and Readiness shall approve the wearing of the uniform for members of the Armed Forces assigned to OSD and the Directors of the Defense Agencies and the Directors of Defense Field Activities for situations under paragraph 3.1.3., and shall ensure the following officials are designed as approval authorities:
4.1.1. The Chairman of the Joint Chiefs of Staff for the Commanders of the Combatant Commands.
4.1.2. The Chairman of the Joint Chiefs of Staff for members of the Armed Forces assigned to the Joint Staff.
4.1.3. The Commanders of the Combatant Commands for members of the Armed Forces assigned to their commands.
4.1.4. The Directors of the Defense Agencies and Directors of Defense Field Activities for the members of the Armed Forces serving within their Agency or Activity.
4.1.5. The Secretaries of the Military Departments for members of the Armed Forces serving within their Military Departments.
4.1.6. The Inspector General, Department of Defense, for members of the Armed Forces assigned to the Office of the Inspector General.
4.2. Officials identified in subparagraph 4.1 may delegate their authority to subordinates; however, under no circumstances may a military officer review and approve the wearing of the uniform for himself, herself, or a military superior.