D.C. Mun. Regs. tit. 20, r. 20-2104
It shall be unlawful for any person to sell, give, or furnish any tobacco products to any person younger than eighteen (18) years of age.
Any person who sells any cigarette or other tobacco product who has reasonable cause to believe that a person who attempts to purchase the product is under twenty-five (25) years of age shall require that the purchaser present identification that indicates his or her age.
The owner, manager, or other person in charge of any business licensed to sell cigarettes or any tobacco product under D.C. Official Code § 47-2404 (2001), shall conspicuously post signs that state, in letters not less than three-quarters of an inch (3/4 in.) in height, the following:
"NO PERSONS UNDER EIGHTEEN (18) YEARS OF AGE SHALL PURCHASE ANY CIGARETTE OR OTHER TOBACCO PRODUCT. THE UNITED STATES SURGEON GENERAL HAS ISSUED A WARNING THAT SMOKING CAUSES LUNG CANCER, HEART DISEASE, EMPHYSEMA, AND MAY COMPLICATE PREGNANCY. MAXIMUM CRIMINAL FINE ONE THOUSAND DOLLARS ($1,000) AND NINETY (90) DAYS IN JAIL."
The owner, manager, or person in charge shall post the sign required by § 2104.3 at the entrance to the business and on the interior of the business near all points of purchase.
D.C. Mun. Regs. tit. 20, r. 20-2104