D.C. Code § 50-2601
It is hereby declared that the free circulation of traffic of all kinds through the highways of the District is necessary to the health, safety, and general welfare of the public, whether residing in said District, or traveling to, through, or from said District in the course of lawful pursuits; that in recent years the greatly increased use by the public of motor vehicles of all kinds has caused serious traffic congestion on the highways of the District; that the parking of motor vehicles on the highways of the District has contributed to this congestion to such an extent as to interfere seriously with the primary use of such highways for the movement of traffic; that such parking prevents the free circulation of traffic in, through, and from said District, impedes rapid and effective fighting of fires and the disposition of police forces in the District, threatens irreparable loss in valuations of property in the District, which can no longer be readily reached by vehicular traffic, and endangers the health, safety, and welfare of the general public; that this parking nuisance can be reduced by providing sufficient off-street parking facilities conveniently located in the several residential, commercial, industrial, and governmental areas of the District; that adequate off-street parking facilities have not been provided by private enterprise; that it may be necessary to supplement private parking spaces by off-street parking facilities provided by public undertaking; and that the enactment of this subchapter, as well as the use of land for the purposes set forth in this subchapter, is hereby declared to be a public necessity.
D.C. Code § 50-2601