Washington, D.C. Admission Act This bill provides for admission into the United States of the state of Washington, Douglass Commonwealth. The Commonwealth shall be admitted to the Union on an equal footing with the other states. The Mayor of the District of Columbia shall issue a proclamation for the first elections to Congress of two Senators and one Representative of the Commonwealth. The Commonwealth shall consist of all Washington, DC territory as of enactment of this bill, with specified exclusions for federal buildings and monuments. The Commonwealth may not impose taxes on federal property except as Congress permits. The bill applies current DC laws to the Commonwealth and continues pending judicial proceedings. The bill maintains: (1) DC as the seat of the federal government, and (2) the federal government's authority over military lands and specified other property. The bill provides for expedited consideration of a joint resolution repealing the Twenty-Third Amendment to the Constitution (which provides for the appointment of electors for President and Vice President).