5 U.S. Code § 6103 – Holidays | U.S. Code | US Law | LII …

January 20 of each fourth year after 1965, Inauguration Day, is a legal public holiday for the purpose of statutes relating to pay and leave of employees as defined by section 2105 of this title and individuals employed by the government of the District of Columbia employed in the District of Columbia, Montgomery and Prince Georges Counties in Maryland, Arlington and Fairfax Counties in …

https://www.law.cornell.edu/uscode/text/5/6103