D.C. Code § 50-1702
As used in this chapter the term:
(5) “Motor vehicle” means any device with more than 3 wheels and a seating capacity of 8 or fewer passengers, exclusive of the operator, which is propelled by an internal-combustion engine, electricity, or steam, and which is designed, used, or maintained for passenger or recreational purposes, or which is designed, used, or maintained for transporting freight, merchandise, or other commercial loads or property.
The term “motor vehicle” does not include any device which is used for livery, sightseeing, taxi, ambulance, funeral, or farm purposes; or any device with more than 3 wheels which is propelled by an internal-combustion engine, electricity, or steam and which has a seating capacity of more than 8 passengers, exclusive of the operator.
Mar. 10, 1983, D.C. Law 4-194, § 3, 30 DCR 49
May 16, 1995, D.C. Law 10-255, § 35, 41 DCR 5193
1981 Ed., § 40-1202.