10 U.S.C. § 2249b

1. (a)The Secretary of Defense shall ensure that, whenever the official flags of all 50 States are displayed by the armed forces, such display shall include the flags of the District of Columbia, the Commonwealth of Puerto Rico, the United States Virgin Islands, Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands.
2. (b)The display of an official flag of a State, territory, or possession of the United States at an installation or other facility of the Department shall be governed by section 7 of title 4 and any modification of section 7 under section 10 of title 4.