In less than a month, the Illinois Cannabis Regulation and Tax Act will come into effect. On Jan. 1, the act will legalize adult-use retail marijuana across the state and bring with it a hefty regulatory framework.

As part of that framework, employers — particularly hospitals, academic medical centers and other employers subject to complex, overlapping and sometimes contradictory workplace regulations — will now be prohibited from firing employees for off-duty marijuana use, requiring an overhaul of most employers’ drug policies.

Previously, Illinois employers could fire employees for failing a drug test (although medical marijuana users are protected by law in Illinois so long as the employee is sober at work).

Marijuana is illegal under federal law, and, until Jan. 1, is also illegal for nonmedical use in Illinois. Under the new act, only employees who are intoxicated on the job can be disciplined or fired for their marijuana use.

Employees fired or disciplined for off-duty use have the right to sue the employer for lost wages and legal fees under Illinois’ Right to Privacy in the Workplace Act.

The major dilemma now facing employers is how to tell if an employee is intoxicated on the job.

No test currently available will show whether a person is intoxicated at that time. In fact, tests for marijuana can return positives for a single use more than a month before the test.

This result is great for employers in states where disciplinary decisions can be made on any positive, but is worse than useless in a state such as Illinois where discipline based on off-duty use can open an employer to a lawsuit, especially since an employer’s knowledge of a positive test result can, in the eyes of a jury, taint any unrelated discipline with the suspicion that it was because of the drug test.

Hospitals are particularly vulnerable to unexpected violations of the act because, while on-call employees are considered on-duty by the act, the act defines “on-call” status as requiring at least 24 hours’ notice — any variation from that definition could lay the groundwork for a lawsuit.

In addition, academic medicine and health-care education programs will find themselves mired in conflicting regulations concerning student-learners in the workplace.

Finally, federal grant recipients are sometimes required to have drug-free workplaces, but several courts around the country have disagreed about what exactly a “drug-free workplace” entails.

Exemptions exist in the act for hospitals and other employers faced with some of the harder cases, such as conditioned federal funding, but a court may not find those exemptions to cover all cases.

Stuck between the metaphorical rock of having possibly intoxicated employees in the workplace and the hard place of a useless drug test, employers who do not take action now to update their human resources policies will be unprepared to deal with the litigation minefield the act is laying for 2020.

Every employer should examine its drug testing, human resources training and disciplinary policies for needed changes. Further, any business receiving federal funds or contracts should comb through the agreements for any federal drug-free workplace requirements as well.