The District of Columbia Voting Rights Amendment was a proposed amendment to the United States Constitution that would have given the District of Columbia full representation in the United States Congress, full representation in the Electoral College system, and full participation in the process by which the Constitution is amended.
This proposed amendment was proposed by the Congress on August 22, 1978. It was ratified by only 16 states by the time of its expiration on August 22, 1985, 22 ratifications short of the needed 38 in order for the proposed amendment to have been adopted.
This amendment is also notable for being the most recent amendment to have been sent to the states for their consideration.
Section 1. For purposes of representation in the Congress, election of the President and Vice President, and article V of this Constitution, the District constituting the seat of government of the United States shall be treated as though it were a State.
Section 2. The exercise of the rights and powers conferred under this article shall be by the people of the District constituting the seat of government, and as shall be provided by the Congress.
Section 3. The twenty-third article of amendment to the Constitution of the United States is hereby repealed.
Section 4. This article shall be inoperative, unless it shall have been ratified as an amendment to the Constitution by the legislatures of three-fourths of the several States within seven years from the date of its submission. 
Representative Don Edwards of California proposed House Joint Resolution 554 in the 95th Congress. The United States House of Representatives passed it on March 2, 1978, by a 289–127 vote, with 18 not voting. The United States Senate passed it on August 22, 1978, by a 67–32 vote, with 1 not voting. With that, the District of Columbia Voting Rights Amendment was submitted to the state legislatures for ratification. The Congress, via Section 4, included in the text of the proposed amendment the requirement that ratification by three-fourths (38) of the states be completed within seven years following its passage by the Congress (i.e., August 22, 1985) in order for the proposed amendment to become part of the Constitution.  By placing the ratification deadline in the text of the proposed amendment the deadline could not be extended, as had been done regarding the Equal Rights Amendment. 
Ratification by the legislatures of at least 38 of the 50 states by August 22, 1985, was necessary for the District of Columbia Voting Rights Amendment to become part of the Constitution. During the seven-year period specified by Congress it was ratified by only 16 states and so failed to be adopted.  The amendment was ratified by the following states:
- New Jersey on September 11, 1978
- Michigan on December 13, 1978
- Ohio on December 21, 1978
- Minnesota on March 19, 1979
- Massachusetts on March 19, 1979
- Connecticut on April 11, 1979
- Wisconsin on November 1, 1979
- Maryland on March 19, 1980
- Hawaii on April 17, 1980
- Oregon on July 6, 1981
- Maine on February 16, 1983
- West Virginia on February 23, 1983
- Rhode Island on May 13, 1983
- Iowa on January 19, 1984
- Louisiana on June 24, 1984
- Delaware on June 28, 1984
Effects if it had been adopted
Had it been adopted, this proposed amendment would have given Washington, D.C. full representation in both houses of the Congress. Also, this proposed amendment would have repealed the Twenty-third Amendment. The Twenty-third Amendment does not allow Washington, D.C. to have more electoral votes "than the least populous State", nor does it grant Washington, D.C. any role in the election of a President by the House of Representatives (or that of the Vice President by the Senate). In contrast, this proposed amendment would have provided Washington, D.C. full participation in the Electoral College. It may have been the case that this amendment would have been interpreted such that selection of the Speaker of the House and the President pro tempore of the Senate would have explicitly and Constitutionally necessarily involved participation of the relevant Congressional representatives of the D.C. Finally, the proposed amendment would have also allowed the Council of the District of Columbia, the Congress, or the people of Washington, D.C. (depending on how this proposed amendment would have been interpreted) to decide whether to ratify any proposed amendment to the Constitution, or to apply to the Congress for a convention to propose amendments to the United States Constitution, just as a state's legislature can pursuant to the Constitutional amendment process. The amendment would neither have made Washington, D.C. a state, nor affected Congress's authority over it.