Cannabis. Marijuana. Weed. Grass. It’s a drug that goes by many names because it has millions of users. According to a 2021 report, approximately 52.5 million Americans, or about 19% of the population, reported using marijuana at least once. That means if you have 100 workers on a worksite, it’s likely that 19 of them have used the drug.
Even if a worker isn’t “waking and baking,” THC—the active compound in marijuana—has residual effects that linger in the body long after intoxication has worn off. These effects, which can include slower reaction times, reduced coordination, and impaired cognitive function, can critically impact tasks like driving or operating machinery. For workplaces—especially those with safety-sensitive roles—marijuana use presents a distinct challenge.
Complexities of Legalization and Protections
Marijuana laws remain a maze of contradictions. At the federal level, marijuana remains a Schedule I controlled substance, yet many states have forged ahead, legalizing its use for medical and recreational purposes. This disparity results in a patchwork system of laws that employers must carefully navigate.
Federal Regulations and DOT Oversight
Thankfully, for industries regulated by federal agencies, there’s no grey area. For example, the Department of Transportation (DOT) requires strict adherence to its zero-tolerance policy for marijuana, regardless of state law. Safety-sensitive employees like pilots, truck drivers, and railway operators are forbidden from using marijuana, whether on or off duty. A positive drug test results in immediate consequences, including removal from safety-sensitive duties until the employee completes return-to-duty procedures. This strict federal stance underscores the tension between state legalization and national oversight.
State-Level Exemptions for Safety-Sensitive Roles
States that have legalized marijuana still recognize the elevated risks it poses to safety-sensitive positions. However, there are some notably less-stringent states:
- New Jersey: The law doesn’t explicitly exempt safety-sensitive positions, though employers are allowed to respond to observable workplace impairment.
- Nevada: While off-duty use is generally protected, the law doesn’t always outline specific exemptions for safety-sensitive roles, leaving room for interpretation.
- New York: Protections exist for off-duty use, but safety-sensitive positions aren’t explicitly exempt, enabling employers to act on their discretion.
This lack of uniformity across states forces employers to closely examine local laws, although they should rest easy that federal law still takes precedence.
Challenges in Unionized Workforces
The issue becomes more complicated in unionized workplaces, where drug policy enforcement is often subject to negotiation. Collective bargaining agreements might require that any changes to workplace drug policies be discussed and approved by unions. Disputes over marijuana testing protocols are also common, with unions frequently challenging policies that they argue unjustly punish employees.
For example, in Washington State, unions representing construction workers have opposed random drug testing, citing the inability of current tests to distinguish past marijuana use from present impairment. These cases often end up in arbitration, with unions advocating for workers’ rights and employers striving to maintain workplace safety.
Building Clear Policies to Mitigate Risk
Employers overseeing safety-sensitive positions must develop comprehensive and unambiguous policies regarding marijuana use. These policies should clearly define safety-sensitive roles and outline the expectations for drug use, testing, and consequences for violations. A zero-tolerance policy for employees in safety-critical roles is often a necessary safeguard, aligned with federal regulations like those of the DOT. However, policies should also specify how issues like observable impairment will be handled, reflecting both workplace safety concerns and compliance with state protections for off-duty use. By communicating these policies transparently, and making explicit that safety-critical roles fall under the purview of federal laws rather than state ones, companies can set clear expectations while reducing overall legal risk.
Training Supervisors to Identify and Manage Impairment
One of the critical hurdles in addressing marijuana in the workplace is identifying impairment on the job. Supervisors should be trained in recognizing signs of impairment, such as delayed reaction times, erratic behavior, or impaired judgment. Employers should invest in reasonable suspicion training, equipping supervisors to document incidents and follow proper protocols. This not only protects the company against legal challenges but also prioritizes immediate action to prevent workplace accidents.
Moving Forward with Clarity and Care
Managing marijuana use in safety-sensitive workplaces is an ongoing challenge as laws and norms shift. It will be necessary to keep a close eye on shifting marijuana policy over the next few years. In the meantime, employers must focus on clear policies, targeted training, and staying informed about legal changes to ensure safety remains a priority. Transparent communication and a culture of accountability are equally critical to maintaining trust while navigating strict regulatory demands
Join our expert-led webinar, “Up in Smoke: Navigating the Haze of Marijuana Policies in 2025,” with Ogletree Deakins employment lawyer M. Tae Phillips and Axiom Medical’s Chief Medical Officer Dr. Scott Cherry to get crucial updates marijuana laws and to learn how to adapt your workplace policies accordingly.
Cain Boney is a contributor to Axiom Medical’s blog. With a career dedicated to writing about the workplace, Cain focuses on how employee well-being affects organizational success and sustainability in the long term.