A Colorado law prohibits employers from terminating an employee for “engaging in any lawful activity of the premises of the employer during nonworking hours…” Another Colorado law allows individuals to obtain a license to use medical marijuana.

The Colorado Court of Appeals has held that licensed medical marijuana use is not a “lawful activity” under the Colorado statute because marijuana use violates federal law. Coats v. Dish Network, L.L.C. (Co. Ct. Appeals, April 25, 2013). The plaintiff, a quadriplegic, had alleged that he was licensed to use medical marijuana and was never under the influence of marijuana at work, but was terminated after he tested positive for marijuana, which established a violation of the employer’s drug policy. 

The focus of the court’s analysis was whether “lawful” meant lawful under state law alone. The court held that because activities conducted in Colorado, including medical marijuana use, are subject to both state and federal law, an activity may be “lawful” only when it complies with both.

With 18 states and the District of Columbia having passed medical marijuana laws, and marijuana use remaining illegal under federal law, employers are likely to face more challenges to their drug policies. The Coats court cited, and employers are likely to rely on, a comment by the California Supreme Court in Ross v. RagingWire Telecommunications, Inc., that “[n]o state law could completely legalize marijuana for medical purposes because the drug remains illegal under federal law, even for medical users.”