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Illustration by Steve McCracken

An Employer's Guide to Marijuana in the Workplace

​Last November, two-thirds of Washington, D.C., residents voted to pass Initiative 71, which decriminalizes the possession of marijuana in the district. The sale and use of medical marijuana became legal in Washington, D.C., in 2010, but Initiative 71 allows for residents 21 and older to grow and consume small amounts of pot at home.

Despite congressional resistance, the D.C. Council took up an emergency measure to prohibit companies from drug testing during preemployment screening. However, companies can still test their existing employees, and fire them if they test positive, because marijuana is still illegal under federal law. It’s a confusing situation for companies, employees, and job applicants, and it is becoming even more complicated in light of lawsuits, federal contracts, contradictory laws, and the evolving perception of marijuana in society at large.

Along with Washington, D.C., 23 states have legalized either medical or recreational use of marijuana, or both. Some jurisdictions, like D.C., have corresponding laws outlining the legality of drug testing job applicants or employees. But federal law overrides state laws and, according to federal statute, marijuana is classified as a Schedule 1 drug—the same classification as heroin and LSD—and is illegal. 

“That’s the linchpin under a lot of these issues,” explains Vance Knapp, a Colorado-based labor and employment lawyer with Sherman & Howard. “It doesn’t matter what the states do in terms of legalizing marijuana, whether that’s recreationally, medically, or both—it’s still illegal under federal law and that has not changed. Even though the federal government has taken a lenient enforcement viewpoint on minor marijuana use, that doesn’t mean it’s legal under federal law. Only an act of Congress can legalize it.”

“The classification raises a lot of eyebrows for a lot of people on both sides of this issue,” notes Jim Shore, a partner with Stoel Rives, LLP, who has worked in labor and employment law for nearly 30 years.

The disconnect between state and federal law, along with ambiguous workplace drug policies, has led to a number of lawsuits against employers, especially in Washington, Oregon, and California. 

The stigma behind marijuana use may also make employers wary of the issue, as illustrated by the name of a recent session held by the Society of Human Resource Management: “Red and Watery Eyes, Slurred Speech, Dorito Crumbs, and Other Red Flags: New Legal Challenges to Drug and Alcohol Testing.”

Knapp says employers need to understand how to navigate the legal, contractual, and cultural issues involved with drug testing in the workplace. “What’s pivotal, though, in these states that have legalized marijuana is that you educate your workforce as to what your expectation is,” he says. “It’s one thing to put it in your employee handbook. It’s another thing to actually educate your employees about what your expectations are concerning their behavior.” 

The issue affects a large portion of the workforce. Approximately 75 million Americans 26 and older have reported using marijuana, and 70 percent of these people are employed full-time. There are also an estimated 2.5 million medical marijuana users in the United States.

Following is a discussion of what employers need to know about the legal minefield of marijuana testing in the workplace, such as conducting preemployment screening, complying with the Americans with Disabilities Act (ADA), and enforcing workplace policies.

Preemployment Screening

The legality of testing potential employees for drug use is generally clear-cut, as many states have some form of law regarding drug testing of job applicants. Most states require that an applicant be notified that drug testing is part of the screening process for new employees. And because conducting medical tests on job applicants can violate federal antidiscrimination laws, employers tend to require a drug test only after the applicant has accepted a job offer. 

“Most employers will give a person a conditional job offer on the condition that they successfully pass the background check and the substance use check as well,” Knapp explains. “That seems to minimize problems. Most Fortune 500 companies do drug testing post-offer as well.”

Washington, D.C.’s measure, The Prohibition of Pre-Employment Marijuana Testing Act, is the first law specifically aimed at preventing discrimination against legal marijuana users by prohibiting employers from drug testing job applicants until they have been formally offered employment. The law simply codifies what has been common practice among employers. 

Marijuana use advocates say this clarification gives applicants who test positive for previous pot use a chance to discuss the test result with their employer—after a company has put time and money into interviewing, screening, and making an offer to a potential employee, it may be more willing to negotiate with the new hire. Indeed, a 2013 HireRight Employee Screening Benchmarking Report, which addressed marijuana use, found that only 63 percent of respondents took adverse action against job candidates who tested positive for marijuana. 

In some states, including Arizona and Minnesota, laws are in place that prevent an employer from discriminating against a job applicant or current employee who tests positive for marijuana, unless failure to do so would cause the employer to lose a monetary or licensing-related benefit under federal law.

There are several situations where this might come into play. The U.S. Department of Transportation (DOT) still drug tests safety-sensitive employees—pilots, school bus drivers, and truck drivers—regardless of state initiatives legalizing marijuana use. Some private subcontractors, especially in the security industry, must agree to screen their employees for drug use lest they lose the contract. And under the Federal Drug Free Workplace Act of 1988, federal contractors must keep drug-free workplaces. However, Shore notes, the act does not require contractors to actively drug test their employees. 

“If companies have a drug-free-workplace drug-testing policy because they have a government contract, that could present an issue,” Shore explains. “In those states that do provide protections for marijuana use, the laws do take into account things of that nature.”

The Office of Personnel Management has issued unambiguous guidelines emphasizing that it is a crime for federal employees to use marijuana.​


Adhering to the ADA, which prohibits discrimination against employees with disabilities, has become a legal sticking point in states where medical marijuana is legalized. Although the act requires employers to make reasonable accommodations to employees with disabilities, the ADA does not explicitly protect employees who use illegal drugs.

Medical marijuana advocates say that employees should be able to use the drug outside of work hours and off the premises, but even this type of use does not mesh with zero-tolerance workplace drug policies. The issue is illustrated in the ongoing Colorado legal case Coats v. Dish Network, in which Brandon Coats, a paralyzed employee, tested positive for THC at his Dish Network job and was subsequently fired. 

Coats argued that he legally used medical marijuana when he was off duty and away from the job site, and that the use was protected under Colorado’s Lawful Off-Duty Activities Statute. However, the case made its way to the Colorado Court of Appeals, which ruled that Coats’ use of marijuana is not covered under the statute because marijuana is illegal under federal law. The case has since moved to the Colorado Supreme Court, which has not yet issued a decision. 

Both Knapp and Shore say that the Coats decision will set a precedent for whether an employer can legally discharge an employee who is using medical marijuana. Knapp notes that although the case deals with medical marijuana, it will have implications for recreational marijuana use as well. 

Although employers do not have to provide a reasonable accommodation for employees who use medical marijuana, they do have to provide assistance to employees who come forward under the ADA’s Safe Harbor provision. For example, if an employee comes forward before a drug test and admits that he has an addiction to medical marijuana, the employer must allow him to enter a substance use treatment program without negative repercussions. 

“That doesn’t mean the employee is free to continue using marijuana—they have to abstain,” Knapp says. “You can drug test them while they’re in the program, and if they test positive then you can fire them.” ​

Workplace Policy

Employers in states with legalized marijuana need to clarify the workplace policy on pot use and educate their workforce on company expectations, Shore says. It may seem easier to just implement a zero-tolerance drug policy, he explains, but that could bring up some unintended complications.

Schedule 1 drugs cannot legally be researched, so there is not enough evidence that can accurately predict how long someone stays impaired after smoking a joint. When a drug test is conducted—often through urine or hair analysis—the presence of THC, the active ingredient in marijuana, will trigger a positive result. However, the DOT notes that THC can remain present in the body for some time after the effects of the drug have worn off—potentially for a month or longer.

“What happens if you have an employee who smoked a joint on Friday night after work, and he comes to work on Monday morning and you do a random drug and alcohol test?” Knapp asks. “You have another guy who drank a fifth of whiskey the night before, and may be really hungover. The guy who smoked Friday night is going to test positive, and the guy who is hungover might not technically be impaired, but his head is pounding—which guy do you want operating your equipment?”

A 2014 Quest Diagnostics Drug Testing Index found that more Americans tested positive for marijuana in 2013 than in 2012—the first time the positivity rate has increased since 2003. “After years of declines, the prevalence of positive workforce drug tests is increasing,” according to a statement by Quest Diagnostics Employer Solutions. “This increase indicates that employers should be aware of the potential for drug use by their workers and the risk that represents for the health and safety of their employees and the public.”

Some employers may decide to implement an under-the-influence policy, in which they treat marijuana like alcohol: employees are not allowed to come to work inebriated, and cannot drink or smoke pot on the premises or during work hours. 

Other employers may consider accommodating the off-duty use of medical marijuana, even if they aren’t required to by law. The 2014 HireRight benchmark report found that 15 percent of respondents have a medical marijuana policy in place.

If an employer does decide to enforce a zero-tolerance drug policy, “hook it on the fact that you expect your employees to be clearheaded, and you just can’t take the risk,” Knapp says. This type of policy is common in the security and healthcare sectors.

It is imperative that employers have a written policy specifically addressing employee marijuana use, Shore notes. “Given the dichotomy between federal and some state law, they need to make sure that the policy covers any drugs that are illegal under both federal and state law. If the employer does not want to get into the still-amorphous area of testing for under the influence, it should have a policy that prohibits any detectable amount of illegal drugs, as opposed to using an under-the-influence standard.”

Another issue employers need to consider is whether their workforce is unionized. “Be prepared to see marijuana come up in collective bargaining and termination negotiation in unionized workforces,” Shore says. “Drug testing in a unionized workforce is a mandatory subject of negotiation, meaning an employer can’t just implement a policy for the unionized workers.”

Both Knapp and Shore say that it’s only a matter of time until the U.S. Supreme Court addresses the classification and legality of marijuana as it is legal in half of the country. There are two bills currently before Congress that would classify marijuana as Schedule 2, which would allow for federally-funded medical marijuana research. 

“I would really like to see the issue addressed on a serious federal level because there are a lot of people saying that marijuana is no worse than alcohol and cigarettes,” Shore says. “We need to get to the bottom of whether it has medicinal properties or not, because if it does, let’s help people who could benefit from its use, while still having workplace regulations.”