But litigants like Coats might see different rulings in other states. “This is really going to come down to states and how states handle these types of employment issues,” says Mason Tvert, the director of communications at the Marijuana Policy Project. "Different states have different laws on the books regarding employment, just like we have some states that are right-to-work states and others that aren't." Tvert notes that Arizona, Delaware, and Minnesota have laws that explicitly protect medical-marijuana patients from being fired after failing a drug test. Others, such as New York and Rhode Island, have similar protection, but don’t refer to drug testing. Still others have no employment protections related to marijuana use.

Colorado may have resolved the question for the time being, but it’s not clear how state and federal laws interact in other places, and the uncertainty leaves patients confused about whether their jobs are safe. Back in 2010, for Coats, this produced a situation in which the results of a drug test would never be a surprise—but his employer’s reaction to the results would be. (Even though no federal law requires that employers give drug tests to their employees, about 40 percent of employers nationwide still do.)

Even if employers aren’t embracing marijuana use, American society appears to be. Nearly half of Americans report having tried it, and four states and the District of Columbia have legalized its recreational use. "We expect the laws to catch up with the culture, and increasingly, employers are not going to want to fire employees for using marijuana off the job and then go through the process of hiring and training.…They will treat marijuana similarly to how they treat alcohol," says Tvert. Coats himself noted the existence of a double standard. He told The New York Times last year: “A person can drink all night long, be totally hungover the next day and go to work and there’s no problem with it.”

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