Tips for Employers Trying to Grapple with Cannabis Use in the Workforce

As more states legalize recreational and medical cannabis, employers, and particularly multi-state employers, face increasingly difficult compliance questions. Among them, can the company discipline — or decline to hire — an individual based on cannabis use outside of work, and what should an employer do if it believes an employee may be working under the influence?

Unfortunately, answers to these questions are jurisdiction and fact dependent. Although cannabis remains unlawful under federal law, a growing number of states and local jurisdictions protect at least some forms of lawful off-duty cannabis use. What’s more, for employers operating across state lines, a uniform “zero-tolerance” drug policy may create unnecessary legal risk.

The Patchwork Is Becoming More Complex

State cannabis laws vary significantly. Some jurisdictions permit employers to maintain drug-free workplace policies and take action based on a positive test. Others (like Illinois) limit adverse action against applicants or employees based solely on off-duty cannabis use or a positive test for cannabis metabolites. Still others (like New York City) prohibit pre-employment cannabis testing altogether.

Many employers understandably point to cannabis’s continued status as a controlled substance under federal law in hopes of getting around this patchwork. But federal illegality does not necessarily provide a complete defense to a claim under a state or local employment law. Still, federal requirements remain critically important. Employers subject to U.S. Department of Transportation (DOT) drug- and alcohol-testing rules, federal contractor obligations, or other industry-specific federal mandates may have greater latitude — or even affirmative obligations — to prohibit cannabis use and take action following a positive test. Likewise, employers generally retain the ability to prohibit cannabis possession, consumption, distribution, and impairment during working time or on company premises. The key is identifying when a federal obligation actually applies, rather than assuming federal law supports a broad policy across the entire workforce.

Impairment in the Workplace Remains a Central Concern

Even states with robust protections for off-duty cannabis use generally allow employers to address on-duty impairment and workplace safety concerns. However, proving on-duty impairment can be more difficult than proving the presence of cannabis metabolites, and permitted methods for proving impairment can vary as well.

A positive drug test alone may not establish that an employee was impaired while working, particularly where the applicable law focuses on current impairment rather than past use. Employers should therefore consider whether supervisors are trained to identify and document objective, contemporaneous indicators of impairment, such as unsafe conduct, erratic behavior, physical symptoms, or a material decline in job performance. For example, Illinois’ Cannabis Regulation and Tax Act goes so far to lay out specific symptoms that employers may look for when evaluating if an employee is under the influence of cannabis. Policies and training should emphasize that supervisors are not expected to diagnose cannabis impairment. Instead, they should document observable workplace behavior and follow established reasonable suspicion protocols.

Steps for Multi-State Employers

In light of the foregoing, employers should consider the following when crafting their cannabis-related policies:

• Review drug-testing and drug-free workplace policies. Determine whether current language is broader than state law allows, particularly as to applicants and off-duty use.
• Create state-specific addenda or protocols. A single national policy may be administratively convenient, but it may not account for jurisdiction-specific restrictions.
• Identify safety-sensitive and federally regulated positions. Clearly define roles subject to DOT, federal contractor, or other specialized requirements.
• Train managers and HR personnel. Ensure that those making employment decisions understand the difference between a positive test, past use, and observable workplace impairment. Employers may even consider specific training for supervisors to identify physical symptoms of impairment.
• Coordinate with testing vendors. Confirm that vendors’ testing panels, reporting practices, and procedures align with applicable state and local rules and do not exceed what the law permits.

Cannabis employment law is evolving quickly. Multi-state employers need not abandon workplace safety or drug-free workplace objectives, and while many jurisdictions still permit zero-tolerance policies, employers should not assume that yesterday’s zero-tolerance policy remains lawful everywhere they operate.