Medical marijuana started flowing a few months ago in New Jersey, after years of delays, but an underlying issue is expected to come front and center as the program becomes more popular. How will this affect employers and employees, particularly those in a drug-free workplace?

The New Jersey Compassionate Use Medical Marijuana Act was written in a way that doesn't force employers to accommodate the use of marijuana on the job. However, many employers will be forced to set boundaries for what can be allowed at the workplace and what can show up in an employee's drug test.

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"If a company has a broad, zero-tolerance drug policy, an employee can not test positive for marijuana, even if it was used legally for medical marijuana purposes," said CJ Griffin, an employment litigation associate at Pashman Stein in Hackensack. "As the other dispensaries open and more patients are qualified for (marijuana), then it will become an issue."

There are a few hundred registered patients for the state's medical marijuana program, which is among the strictest across the nation in terms of qualifying conditions and strength of the product. Greenleaf Compassion Center opened in Montclair last December, with five more opening at some point in the future. More patients will register for the program and possibly open the flood gates to employer-employee battles.

Griffin said there have been cases nationwide on this issue, and the cases have overwhelmingly turned out in favor of the employers.

"The reality is marijuana remains an illegal drug at the federal level, and that's the catch that employers can use to keep it illegal in their workplace policies," Griffin said.

She advised employers and employees to be cautious and seek legal counsel before pursuing any course of action, should a situation arise.