Although it’s legal under state law to use marijuana, the Colorado Supreme Court ruled today that employers can fire workers who smoke/ingest/otherwise partake in pot when they’re off the clock.

A former employee of Dish Network who had a medical marijuana card and consumed marijuana while off-duty to control muscle spasms was fired in 2010, reports the Denver Post. He then challenged Dish and its policy, claiming because his use was legal under state law, he shouldn’t be fired.

But the firing was upheld in both trial court and the Colorado Court of Appeals before today’s 6-0 decision [PDF] from the state Supremes.

While using medical marijuana is in compliance with Colorado’s Medical Marijuana Amendment, the justices had to consider whether it’s still lawful under the state’s Lawful Off-Duty Activities Statute. That term includes activities lawful under both state and federal law, the justices said.

“Therefore, employees who engage in an activity such as medical marijuana use that is permitted by state law but unlawful under federal law are not protected by the statute,” Justice Allison H. Eid wrote in the opinion.

It’s up to employers in Colorado to set their own policies on drug use, so this means that anyone using marijuana legally under state law could still find themselves in trouble with their bosses under federal law. This could have implications for other states that allow marijuana use, as well, as companies figure out what to do when facing both state laws and federal law.

Everything could be different in the future, however, if the federal law regarding marijuana use ever changes. Until then, better check that employee handbook.

Colorado Supreme Court: Employers can fire workers for off-duty marijuana use [Denver Post]

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