I'm an HR pro by trade and I recently went to an employment law seminar. The topic? The implications of medical marijuana in the workplace.

The speaker who opened the session was a lawyer, and let's just say he didn't present medical marijuana in an objective, balanced light. Quite the opposite, really.

He began by saying there were more marijuana dispensaries in Vancouver than Starbucks, a story Civilized covered recently. The jury's out on whether that's true or not.

But he shocked the conservative HR audience, which I believe was his intention. He went on to use terms like "stoner" and "pothead." He referred to employees leaving their "hash brownies" in the lunchroom and said medical cannabis is "not a real drug." He said all of this to a group of HR professionals who, like most of the population, are not well-educated on medical marijuana because it's a relatively new trend.

Now think about this. These are the professionals responsible for accommodating employees in the workplace who use legal cannabis to treat a medical condition.

HR professionals need to be open-minded, respectful

Understanding, tolerance, and an objective approach are needed for these situations to be handled successfully. In Canada, accommodation is a legal requirement, not one that can be ignored based on a person's biases. Biases and prejudices are exactly how employers get in trouble with human rights issues.

The lesson? The stigma is alive and well. The stigma hurts medical marijuana credibility big time, especially when being introduced to a new audience that has limited experience with the topic.

But, I get it. There is limited clinical information about the medical efficacy of cannabis because it has been a controlled substance for so long. I can't deny that. It isn't a "real drug" based on traditional North American standards. It's not FDA approved. It has no drug identification number.

So the seminar was a sobering experience in many ways. It was a reminder of how much work there is to build awareness about the medical benefits of cannabis.

But change is coming. Clinical trials are starting. There is compelling evidence that medical cannabis can help sick people in amazing ways. Many countries are moving towards legalization. Canada. The United States. Ireland. Australia. Mexico.

The workplace needs to be ready for these changes sweeping the world.

Alison McMahon is a workplace expert based in Alberta, Canada and the Founder of Cannabis At Work. Follow her on Twitter and LinkedIn where she provides overdue commentary on weed + work.