The email from my new job was not the welcome I was anticipating. I would “be required to complete a drug test within 72 hours,” it said. “Please be sure to check your email for instructions.” It was August 2018, and I had just accepted an offer as a faculty member to develop a research program on, of all things, cannabis’s therapeutic effects on chronic pain. But in addition to being a cannabis researcher, I have fibromyalgia, and I had been using legal medical cannabis for nearly 10 years to help manage my symptoms.

Cannabis byproducts can be detected in urine for weeks, but I did what I could: I immediately stopped taking my medicine, exercised frequently, drank water constantly. My test kept getting delayed, which was lucky in one sense: By the time I took it, I was clear. But I had gone two months without my only useful pain medication.

And for what? All the test showed was that I had avoided cannabis and other drugs during the preceding weeks. I could have partied for the rest of the year, and no one would have been the wiser.

Perhaps you’ve experienced this pointless exercise. A staggering number of people have. Despite the fact that 38 states have legalized medical cannabis, many employers continue to require their new hires to submit to a drug test.

Often these employers, including universities like mine, say the law leaves them no choice. The Drug-Free Workplace Act of 1988 and the Drug-Free Schools and Communities Act Amendment of 1989 do, indeed, require federal employees involved in certain professions, like law enforcement and national security, to be tested. That may be changing: Last month The New York Times reported that over the past five years, the military has given thousands of recruits a second chance to pass. In any case, these statutes do not mandate drug testing for people not employed by the federal government, even — despite many claims to the contrary — those who receive federal funding, such as academic researchers.

Cannabis can, of course, get you high, which affects attention, memory and learning. So just as most employees aren’t allowed to drink alcohol on the job, it makes sense that most employers don’t want people using cannabis while they’re working. The problem is that job-site drug screening captures usage only in the recent past. It does not assess current impairment or predict whether an employee may be a future safety risk.

Further, many other substances, including prescription medicines such as opioids, benzodiazepines and antidepressants, can also cause impairment. As long as you have a prescription, an employer can’t penalize you for taking benzos. Why should it be different for medical cannabis? As for those using it recreationally, unless they are showing up to work high or impaired, does it matter?

Even CBD products, which can’t get you high and aren’t controlled substances, may contain a compound that can trigger a positive urine drug screen.

Given President Biden’s recent call for the Food and Drug Administration to review whether cannabis should be a controlled substance in the first place, it’s beyond time to stop pre-employment drug testing for it. These policies are punitive for the nearly three million people who have medical cannabis licenses, as well as the millions more who simply use nonintoxicating CBD products. In addition to wasting substantial time and money and causing a great deal of unnecessary stress, such policies may worsen symptoms for people using these products medically — as I found out firsthand.

I publicly disclosed my medical cannabis use on two previous occasions: in an article in a major medical journal in December 2018 and in a large talk I gave in 2022. Neither disclosure resulted in a drug test. I doubt I will be tested when this article is published. (Stay tuned!) Such uneven enforcement makes me suspect that some employers don’t actually care; they are simply checking a box that doesn’t really need to be checked. Since there’s no genuine safety or legal reason to keep doing this, isn’t it time we let new hires urinate in peace?

Kevin Boehnke is a research assistant professor and the director of controversial compounds in the University of Michigan Medical School’s department of anesthesiology and Chronic Pain and Fatigue Research Center.

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