The possession, distribution, and use of cannabis remains illegal under federal law. Consequently, in isolation, employers may believe that enforcing their zero-tolerance policies for drug use (as referenced here, zero-tolerance refers to policies that prohibit any on-duty or off-duty use of unlawful cannabis products) remains a defensible position, including in response to employee complaints that such policies restrict employees’ otherwise permissible use of cannabis products. But how does state legalization of recreational and medical cannabis use fit into the mix? As states become increasingly tolerant of cannabis use, employers may need to reconsider whether their anti-drug and drug-testing policies are compliant with applicable law in order to minimize the risk of discrimination or failure-to-accommodate claims resulting from the employer’s restrictions on the purportedly lawful use of cannabis products.

States grant different levels of protections for cannabis use. Some states prohibit cannabis use in accordance with federal law. Others have legalized medical and/or recreational cannabis use and specifically prohibit employers from taking any adverse employment action against an employee for lawful off-duty conduct. And still others fall somewhere in between. Notwithstanding their varying levels of protections for cannabis use, states do not require employers to permit cannabis use on their premises, nor must employers allow employees to be under the influence of or impaired by cannabis products while on duty. Additionally, some states allow employers to enforce stricter policies for those cannabis users working in “safety-sensitive positions” (as defined by state law).

Employers in states that have not legalized cannabis are likely free to strictly enforce zero-tolerance drug-free policies and implement drug-testing procedures according to their individualized preferences and state law. Conversely, in jurisdictions where cannabis use (both medically and recreationally) is lawful, zero-tolerance policies are generally not recommended because—although cannabis is considered an illegal substance under federal law—many state laws provide greater protections for cannabis users. To avoid liability, an employer will need to consider those protections when drafting and implementing drug-related policies.

Employers in states that have legalized cannabis should take the following actions to scrutinize their anti-drug and drug-testing policies and procedures:

• Consider whether workplace drug testing is necessary or appropriate for particular jobs—it is one thing to require drug tests for safety-sensitive positions, but it may not make sense to test for cannabis use for roles that do not directly implicate public safety, such as an office administrator position. Employers may also choose to remove cannabis from their testing panel altogether, potentially allowing them more flexibility in enforcing their zero-tolerance policies.
• Ensure compliance with laws relating to antidiscrimination and workplace accommodation. Historically, courts have broadly concluded that, because of the illegality of cannabis under federal law, employers could enforce zero-tolerance policies without risking liability for adverse actions against employees resulting from cannabis use.  Today, however, claims regarding discrimination and accommodation may be more viable. Recent cases, in addition to proposed and enacted legislation, have trended toward interpreting statutory language to protect employees for conduct specifically permitted by state law. This can extend to requiring employers to accommodate employees’ medically authorized, off-premises cannabis use.
• Set forth a detailed description of the circumstances under which a drug test will be required and the standardized procedures for testing employees in such situations. To minimize exposure for adverse actions against authorized medical cannabis users, an employer might consider changing its policy to require testing only after an accident or under circumstances creating a “reasonable suspicion” of impairment. Managers should receive training to understand the “reasonable suspicion” standard and recognize when it necessitates a drug test. Separately, the implementation and application of a standardized process decreases the likelihood of complaints that one employee was singled out or treated less favorably than others.
• Provide a detailed description of what is considered evidence of on-the-job impairment and the procedures that will be used in response to suspected impairment. Some states specify that evidence of impairment—or actual proof of impairment—is required before an employer can take an adverse employment action against an employee. Proof of actual impairment is difficult, however; currently, there is no test that assesses the level of an individual’s actual impairment. The effect of a certain concentration of THC (tetrahydrocannabinol, the main psychoactive compound in cannabis) varies from person to person. In response to suspected impairment, an employer should require management to submit a written report documenting the impairment signs exhibited by the employee, including notes of observations by any other witnesses. By requiring such documentation, employers who take adverse employment action will have evidence to respond to an employee’s claims of unlawful treatment.

Notwithstanding the information set forth above, the law is continually evolving in this area. Employers should therefore take care to keep abreast of legal changes and, if necessary, promptly modify their policies and procedures to stay in compliance. Given the continued trend toward cannabis legalization, zero-tolerance policies may soon become intolerable.