CHICAGO (WLS) -- Recreational marijuana use will be legal in Illinois in less than a week, and some companies with zero tolerance policies are deciding how to handle employees who want to light up.
RELATED: Illinois Weed Legalization Guide
With the implementation of the new law fast approaching, companies are scrambling to get policies in place that reflect legalization.
"I've had a lot of questions from my clients on what to do about their zero tolerance drug policies," said Margo Wolf O'Donnell at Benesch Law. "The answer is they can still have those policies as long as they are crafted correctly."
Wolf O'Donnell has been guiding employers on how to legally handle the legalization of marijuana. While the Illinois Privacy Right to Workplace Act allows the use of weed in non-working hours, the new marijuana laws lets employers take adverse action against an employee if they are using marijuana on the job. The issue is that may be hard to prove, because pot stays in your system for days.
"We don't have the testing yet to be able to discern whether or not cannabis was used on that particular day or many days earlier that's the issue, the testing hasn't caught up with the law yet," she said.
RELATED: Illinois Weed Legalization Guide: Will your city or town sell marijuana?
The issue of firing an employee over the use of pot is likely to wind up in the courts, as it has in other states.
"In some states it's been upheld, in other states it's been overturned," said Andy Challenger of Challenger, Gray & Christmas.
The consulting firm is not only busy educating themselves on the new law for their own employees, but also advising other companies. Challenger said businesses need to be prepared for employee questions.
"It is so important to put out a communication before January 1 and let your employees know where you stand on the issue and what your policies on testing are going forward," Challenger said.
Regardless of any new law, any companies with positions that operate heavy machinery can maintain strict zero tolerance policies. Additionally, businesses with employment contracts with federal agencies must follow the federal law.
Marijuana is still illegal on the federal level.