Employers will ignore Mary Jane at their own peril in the wake of recent changes to Canada’s medical marijuana system, says one employment lawyer.

Companies should be prepared to accommodate a growing number of workers on weed after the federal government brought in its new regime, known as the Marijuana for Medical Purposes Regulations (MMPR). Under the new guidelines, a patient must obtain a prescription for marijuana that they can bring to a federally licenced grower.

Employers have to understand their legal obligations when facing an employee with a pot prescription, according to employment lawyer David Whitten, including the fact that they must find a way to accommodate the employee’s need to  use the drug in the workplace.

Currently, an estimated 40,000 Canadians treat various conditions with pot. But Health Canada estimates that nearly half a million Canadians will be using medicinal marijuana within 10 years.

“Employers are going to ignore Mary Jane at their own peril,” Whitten told CTVNews.ca in a telephone interview. “She’s coming to the dance whether they like it or not.”

So what are the most pressing issues that both medicinal marijuana users and their employers should know about? Here are Whitten’s top pieces of advice.

Employers, educate thyselves

Stereotypes about pot users abound, and Whitten says the first thing employers should do is read up on marijuana’s medicinal properties.

An employer presented with a medicinal marijuana prescription can also take steps such as sending a questionnaire home with the employee to be filled out by a physician. This way, an employer can find out answers to key questions, such as how much marijuana the employee is required to take and what parts of the employee’s job may be affected by consumption.

“The reality is is that we’ve recognized this as having medicinal qualities,” Whitten says. “So keep a straight face when somebody comes to you with a prescription, understanding that it needs to be treated legally like any other medication.”

If an employee presents their employer with a prescription that says they need to be able to use medicinal marijuana at work, “there is now an onus to accommodate the medical use of marijuana in the workplace to the point of undue hardship,” Whitten says.

Simply put, it’s the extent to which an employer can accommodate an employee’s medical requirements without causing unreasonable harm or disruption to the business or the work environment.

Create a pot accommodation plan

Before an employer can say that the use of medical marijuana in the workplace cannot be accommodated, it must be demonstrated that every potential possible concession has been investigated and all opportunities have been exhausted, Whitten says.

What does accommodating a pot user at work look like? It can mean different things, but an employer does not have to create an entirely different job just to keep the employee on the payroll. If there are concerns that the employee won’t be able to fulfill certain duties, a reasonable accommodation could be that some duties are shuffled from one employee to another, Whitten says.

One thing an employer cannot do is fire an employee over concerns that he or she could be too stoned to work.

“It’s the same as if anybody had, for example, carpal tunnel syndrome and because of that their production goes down,” Whitten says. An employer can only say that the use of medicinal marijuana cannot be accommodated if he or she can prove that an expected decline in production cannot be made up for by other workers. Or, by showing that it would have a significant financial impact on the business, Whitten says.

“It’s quite a high standard to meet.”

While an employer cannot fire an employee or bar the use of the drug completely, he or she can request that it be ingested rather than smoked if a smoking area cannot be created at work.

Employees have obligations, too

An employee who is taking a drug such as an antibiotic may choose not to report it to the boss unless the medication will have a serious impact on the ability to do the job.

However, an employee with a marijuana prescription should inform the boss because failing to disclose it means the right to reasonable accommodation is forfeited.

“An employer is not required to accommodate a secret prescription,” Whitten says. “So you only really engage the protection of the legislation, of the Human Rights Code, by disclosing to your employer that you have a prescription. Because then you run the risk of getting caught stoned in the office and then whipping out your prescription at the 11th hour.”