Yes — in Illinois, your employer can still fire you for marijuana use if you are impaired at work or violate workplace drug policies, even though cannabis is legal in the state.
Illinois legalized both medical and recreational cannabis, but employers retain significant control over workplace rules:
Drug-free workplace policies: Employers may enforce zero-tolerance policies. If you test positive and they believe you are impaired on the job, they can discipline or terminate you.
Off-duty protections: The Cannabis Regulation and Tax Act protects employees from being fired solely for legal, off-duty cannabis use. Employers cannot discriminate against you for consuming cannabis outside of work hours.
Impairment at work: If an employer has a good-faith belief that you are impaired or under the influence while working, they can take action. This includes observable signs such as decreased performance, unsafe behavior, or physical symptoms.
Medical marijuana patients: Illinois law does not require employers to accommodate medical cannabis use in the workplace. Patients are protected from discrimination for being registered, but they are not allowed to be impaired during work hours.
Federal law conflicts: Cannabis remains illegal federally. Employers subject to federal regulations (transportation, defense, healthcare, etc.) may prohibit cannabis use entirely, regardless of Illinois law.