D.C. Mun. Regs. tit. 18, r. 18-602
The Director is authorized to issue inspection stickers and provide for the attachment of inspection stickers to motor vehicles.
Inspection stickers may indicate approval, rejection, or condemnation of any vehicle, in accordance with the provisions of this chapter.
Vehicles bearing special bus identification, current dealer tags, transport tags, special use paper tags, or historic motor vehicle tags shall be exempt from the inspection sticker requirements of this section.
It shall be unlawful for any person to operate, park, or permit to be operated or parked on public space any vehicle bearing current District of Columbia tags, except a vehicle exempt under the provisions of § 602.3, unless there is displayed on the right side of the vehicle's windshield one of the following:
Whenever a person located in the District of Columbia acquires a motor vehicle which displays on the windshield a valid approved inspection sticker issued by any State that has a compulsory motor vehicle inspection law, that vehicle may be operated without the requirement of any other inspection sticker for a period of fifteen (15) days from the date of acquisition of the vehicle or until issuance by the Director of a sticker containing the words TEMPORARY STICKER - NEWLY REGISTERED VEHICLE, whichever is the shorter period.
No later than the fifteenth (15th) day, the vehicle shall be presented for official inspection as required and shall display only the inspection sticker issued by the Director.
A vehicle owned by a non-resident and currently registered in another jurisdiction shall display the proper inspection sticker issued for the vehicle in accordance with the requirements of the issuing jurisdiction.
D.C. Mun. Regs. tit. 18, r. 18-602