D.C. Code § 47-1041
The real estate described for assessment and taxation purposes as lot 84 in square 197, in the City of Washington, District of Columbia, owned by the American Association of University Women, Educational Foundation, Incorporated, a District of Columbia corporation, is hereby exempt from all taxation so long as the same is owned, occupied, and used by the American Association of University Women, Educational Foundation, Incorporated, for its educational and other corporate purposes, or is jointly occupied with the American Association of University Women, a Massachusetts corporation organized not for profit, for its educational and other corporate purposes, and is not used for commercial purposes, subject to the provisions of §§ 47-1005, 47-1007, and 47-1009.
D.C. Code § 47-1041