Rapidly changing state marijuana laws may challenge surgery centers to write ironclad policies regarding drug testing and screening. Any decision made one day could be put in peril by new or updated regulations the next day.

“States continue to put out new regulations and guidance,” says Natalie P. Hartenbaum, MD, MPH, FACOEM, president and chief medical officer, OccuMedix in Dresher, PA. “Illinois just came up with a recreational marijuana law, and then the legislative body in Illinois came out with modifications and clarifications. There are bills in Congress that might affect the whole marijuana and CBD industry, and the [FDA] is looking at cannabinoids in general.”

To date, the FDA had approved only one CBD product, a prescription drug used to treat two rare forms of epilepsy.1

Surgery centers should contact their attorneys to learn how state laws affect their drug-testing practices, says Geoffrey Mort, an attorney at Kraus & Zuchlewski LLP in New York City. Mort specializes in employment law, and serves on the New York State Bar Association Committee on Cannabis Law.

Generally, state marijuana laws can be placed in three categories, according to Mort:

Fewer than one-third of states still have not legalized marijuana for either medical or recreational use. In these states, employers can refer to federal law, which still makes it illegal to use and sell marijuana. Employers may screen job applicants for marijuana use and drug test employees for THC. Healthcare employers might institute a zero-tolerance policy; any worker who tests positive for THC, even if it is from legal CBD use, could be disciplined or fired.

More than 30 states have passed medical marijuana or compassionate care bills, and some of these also have legalized marijuana use for adults for recreational purposes. In these states, absent an antidiscrimination provision, employers can drug screen and conduct random drug tests. They can institute zero-tolerance policies. Courts usually will uphold their decisions.

More than 10 states have passed antidiscrimination provisions in addition to compassionate care laws. These statutes prohibit employers from discriminating against employees, by firing them or taking legal action against them, because of their use of medical marijuana, Mort says. In these states, employers could be sued for rescinding an employment offer or firing an employee who tests positive for THC.

“We’ve only seen this in the last two years,” Mort reports. “In those states, employees have significant rights.”

In states without antidiscrimination provisions, employees might not prevail in a court case, as demonstrated several years ago in a Colorado case involving Dish Network. In 2010, Dish Network fired a customer service employee, a person with quadriplegia who used medical marijuana. The employee’s performance reviews were positive, but he tested positive for marijuana. The employee filed a wrongful termination lawsuit against Dish, but lost the case. Later, the Colorado Supreme Court upheld the decision, ruling that medical marijuana use was unlawful under federal law.2

“Until 2016, with a few exceptions, employers almost always won these cases,” Mort explains. “The reason they did is because they relied on a doctrine called preemption, which says that if there are state laws and federal laws that contradict each other, then the state law undercuts the purpose of the federal law, and the federal law trumps the state law.”

In states with antidiscrimination provisions, employees have won some significant federal court cases. Mort offers two examples of recent federal cases involving THC tests:

• In Connecticut, which placed an antidiscrimination provision in the state’s Palliative Use of Marijuana Act, a U.S. district court decided in 2018 in favor of a woman who claimed discrimination after an employer rescinded a job offer because of a positive THC drug screening test.

The plaintiff had disclosed her marijuana use to her potential employer, saying she used the drug for medical purposes (treating PTSD). The employer gave her a drug test anyway. When the results returned positive for THC, her job offer was withdrawn. The woman sued, and the court ruled that a federal contractor can employ someone who uses illegal drugs outside of the workplace, even if they prohibit drug use at work.3

• In Arizona, a Walmart employee sued the company after she was fired when a blood test returned positive for THC. The woman owned a medical marijuana registry card. Her lawsuit claimed discrimination under the Arizona Medical Marijuana Act.

The trial court ruled in favor of the employee, saying the company could not claim that the woman was under the influence of marijuana while at work based solely on the drug test.4

Surgery centers and other employers in those states should take the antidiscrimination provision seriously and perhaps think twice about firing an employee who tests positive for THC, Mort advises. “Employers would be well-advised to let it go.”

If employers insist on drug testing, then they should realize that if a person who tests positive for THC is a medical marijuana user and owns a medical marijuana state registration card, that employee can use medical marijuana legally. The employer is prohibited from firing or taking action against the person.

“A significant point that is underlying all of this is that drug testing is becoming more and more out of favor,” Mort says. “A lot of companies look at it as an anachronism, something that doesn’t accomplish anything because drug tests for marijuana are very imprecise.”

With alcohol testing, employers can tell how much alcohol is in one’s blood and whether the level is high enough to cause impairment. That is not true of marijuana/THC testing. Marijuana can stay in a person’s body longer, and it is impossible to pinpoint when a person last used a THC product.

For example, an employee could smoke marijuana once while on vacation and test positive for THC three weeks later. One small study revealed that one-third of people who vaped CBD cannabis tested positive for THC in urine tests.5

“I spoke with someone recently who had never used marijuana, but has used over-the-counter CBD. This person came up with a positive THC result on the drug test,” Mort recalls. “The employer sided with the employee, and ignored the test results.”

Such inaccuracies are leading more employers to turn away from drug tests for marijuana. In healthcare, if a physician uses medical marijuana to help prevent seizures, then an employer would be better off not testing that individual — so long as the doctor’s performance is good, Mort says.

“I don’t think it’s in an employer’s interest to have a zero-tolerance drug testing policy; that’s unrealistic,” Mort offers. “Such a significant percentage of the population uses marijuana that it’s self-defeating.”


  1. U.S. Food & Drug Administration. What you need to know (and what we’re working to find out) about products containing cannabis or cannabis-derived compounds, including CBD. Available at: http://bit.ly/390PJw2.
  2. Canna Law Blog. Coats v. Dish Network and firing employees for cannabis, April 7, 2016. Available at: http://bit.ly/2PKB0y5.
  3. Brodrick CK, Stretton JG. Connecticut court rules in favor of medical marijuana user in discrimination case. Ogletree Deakins, Jan. 2, 2019. Available at: http://bit.ly/2Q8qS0H.
  4. Creative Business Resources. Employee’s discrimination case involving medical marijuana usage provides warning to employers. Available at: http://bit.ly/3s2TauZ.
  5. Spindle TR, Cone EJ, Kuntz D, et al. Urinary pharmacokinetic profile of cannabinoids following administration of vaporized and oral cannabidiol and vaporized CBD-dominant cannabis. J Anal Toxicol 2019; Nov 4. pii: bkz080. doi: 10.1093/jat/bkz080. [Epub ahead of print].