As used in this subchapter, "acquiring authority" means the head of an executive department or agency of the United States, or other officer of the United States, or board or commission of the United States, authorized by law to acquire real property in the District of Columbia for the construction of public buildings or works, or for parks, parkways, public playgrounds, or other public purpose.
D.C. Code § 16-1351
Metropolitan Area Transit Authority, eminent domain powers, see § 9-1107.01. .