Can You Fire an Employee for Marijuana Use in Illinois?

 Posted on September 19, 2025 in Employee Rights

Although Illinois legalized recreational marijuana on January 1, 2020, this does not give employees a free pass to show up to work impaired. Employers must maintain safe, productive workplaces, particularly in industries that involve public safety, healthcare, or transportation. The laws regarding marijuana use in the workplace are nuanced.

Employers must ensure their policies are balanced with employees’ rights under the Illinois Cannabis Regulation and Tax Act (410 ILCS 705/) and other state employment laws. The CRTA explicitly allows employers to maintain a "reasonable zero-tolerance" or drug-free workplace despite the recreational legalization of marijuana.

This does not mean that discipline and termination are always straightforward. The slightest misstep on the part of an employer can result in costly legal battles from wrongful termination or discrimination claims. An experienced Schaumburg, IL employment law  attorney can help ensure your business remains free of expensive lawsuits from employees.

What Are Employers’ Rights Under Illinois Law Related to Employee Marijuana Use?

Employers are allowed to enforce drug-free workplace policies in Illinois, but they cannot legally take action against an employee for off-duty cannabis use unless that use results in workplace impairment. In other words, the right of employers to maintain a safe workplace takes precedence. Under the CRTA, employers can do the following:

• Prohibit employees from using cannabis or being under the influence of cannabis in the workplace, when performing job duties, or while on call.
• Enforce zero-tolerance policies as long as those policies are applied consistently and in a nondiscriminatory manner.
• Apply zero-tolerance policies to off-duty conduct in some situations.
• Discipline or terminate an employee for violating company employment policies or drug policies.
• Perform pre-employment, random, and reasonable-suspicion drug tests. (Taking adverse action based only on a positive test is risky, since with cannabis, a positive result does not necessarily prove impairment.
• Impose strict drug policies for positions requiring adherence to federal regulations and safety-sensitive jobs.
• Act on a good-faith belief that an employee is impaired in the workplace if that belief is backed up by specific, observable symptoms such as a disregard for safety, poor coordination, or other unusual behavior.

What Employers Should and Should Not Do Regarding Cannabis Use in the Workplace

An employer may not terminate or refuse to hire an individual based solely on his or her off-duty use of cannabis. If an employer disciplines an employee based on suspicion of impairment, the employee must be given a reasonable opportunity to contest the disciplinary action. Employers should ensure there are clear, nondiscriminatory drug and cannabis policies in place, with definitions of "workplace" and "on-call." Consequences for policy violations should be unambiguous, and policies must be consistently applied to avoid discrimination claims.  All managers and supervisors should undergo training regarding spotting impairment.

Marijuana Discipline in Illinois is a Delicate Balance

Employers in the state must walk a very fine line between maintaining workplace safety and respecting employee rights. Evolving state and federal laws may impact employer rights, so it is essential to stay informed about changes in applicable laws. Anticipated litigation areas regarding cannabis use in the workplace could potentially involve wrongful termination, discrimination, privacy claims, or disability accommodations.

Contact an Illinois Employment Law Attorney

If your business is uncertain about whether its current policies comply with Illinois law, they should be reviewed. An experienced Schaumburg, IL employment lawyer from The Miller Law Firm, P.C. can help you craft clear, enforceable workplace rules regarding marijuana, as well as defend against employee claims. Attorney Miller has an MBA in Finance, in addition to his law degree, and will aggressively defend your rights as an Illinois employer. To schedule your free consultation, call 847-995-1205.