The District of Columbia’s recent legalization of less than two ounces of marijuana for persons over 21 years of age or older, and decriminalization of less than one ounce for people of any age, has no impact on the District’s existing impaired driving laws.  In the District, it remains illegal to operate or to be in physical control of any vehicle while intoxicated or while under the influence of drugs, alcohol, or a combination of the two.  See DC Code §50-2206.11.  A drug is defined as any chemical substance that affects the processes of the mind or body, including but not limited to a controlled substance, and any prescription or non-prescription medication.  See DC Code §50-2206.01 (6).  One is under the influence of a drug when one’s ability to operate a motor vehicle is impaired in way that can be perceived or noticed.  SeeCriminal Jury Instruction for the District of Columbia 6.400.  Simply put, you cannot drive under the influence.  That remains true for alcohol, and it holds true for marijuana. 

Although possession of certain quantities of marijuana has been legalized or decriminalized, it is illegal to smoke or otherwise consume marijuana in a public space or in a vehicle.  The Office of the Attorney General prosecutes public consumption violations and DUIs.

While decades of research have brought the dangers of alcohol impaired driving to light, it has only been in more recent years that drug impaired driving has been studied.  The National Highway Traffic Safety Administration (NHTSA) recently reported that although alcohol impaired driving has declined over the years, marijuana and other drug impaired driving has increased.  Marijuana, like any drug, can be impairing.  Police officers remain vigilant in their efforts to detect impaired drivers and keep the District’s roads safe.