Driving while impaired (DWI) by cannabis is not new. In fact, this crime has been occurring since the invention of the automobile. The legalization of marijuana in some U.S. states, however, means that communities are discussing this topic at a frequency never before seen. In Colorado, where marijuana has been legalized for medical and recreational use, law enforcement leaders routinely field many questions from community members and politicians about how law enforcement is addressing the crime of DWI-cannabis. The answer is the same as it has been for more than 20 years: DUI enforcement, standardized field sobriety tests (SFST), Drug Recognition Expert (DRE) evaluations, and toxicology testing. The crime of DWI has not changed just because the substance is now legal.