D.C. Mun. Regs. tit. 18, § 1305
1305.1 No resident of the District of Columbia shall drive a commercial vehicle unless he or she has been issued a valid commercial driver license or a valid commercial learner permit, which authorizes him or her to operate the following types of vehicles:
(a) A single vehicle, or a combination of vehicles, with a gross vehicle weight rating of over twenty-six thousand (26,000) pounds, or a lesser rating as determined by Federal regulations, but not less than a gross vehicle weight rating of ten thousand (10,000) pounds;
(b) A vehicle designed to transport more than fifteen (15) passengers, including the driver;
(c) A vehicle used to transport a material found to be hazardous in accordance with the District of Columbia Hazardous Materials Transportation and Motor Carrier Safety Act of 1988, effective March 16, 1989 (D.C. Law 7-190; D.C. Official Code §§ 8-1401 et seq.) and that are required to be placarded under Federal regulations, 49 C.F.R. part 172, subpart F; or
(d) A school bus or a multi-purpose school vehicle.
1305.2 No resident under the age of twenty-one (21) may be issued a commercial learner permit or commercial driver license.
1305.3 No person shall drive a commercial motor vehicle in the District of Columbia unless the person holds a commercial driver license with the applicable class and endorsements for the vehicle(s) he or she is driving, except when driving under a commercial driver learner permit and accompanied by the holder of a commercial driver license for the vehicle being driven.
1305.4 Commercial drivers shall be held to the same standards that apply to anyone who drives in the District of Columbia without a valid operator's permit, as provided in § 7(d) of the District of Columbia Traffic Act of 1925, effective September 27, 1985 (D.C. Official Code § 50-1401.01(d)).
SOURCE: Final Rulemaking published at 39 DCR 732 (February 7, 1992); as amended by Final Rulemaking published at 51 DCR 10913 (November 26, 2004); as amended by Final Rulemaking published at 53 DCR 2206 (March 24, 2006); as amended by Final Rulemaking published at 60 DCR 10071 (July 12, 2013); as amended by Final Rulemaking published at 62 DCR 13453 (October 16, 2015).