What employees should know about marijuana and the workplace

In the lead-up to recreational marijuana legalization on Wednesday, some Canadian employers have adopted restrictive policies around its use.

Airlines such as Air Canada and WestJet have prohibited cannabis consumption on and off-duty for employees in "safety-critical"positions, like pilots and flight attendants.

The RCMP and several police forces across the country, including the Halifax Regional Police, have adopted policies barring officers from marijuana use within 28 days of working.

But in other workplaces the rules may not yet be so clear.

The CBC's Portia Clark spoke with Jill Houlihan, a Halifax labour lawyer and partner at Pink Larkin, about the limits employers can place on recreational cannabis use. Here is part of that conversation.

Are employers allowed to dictate how employees use cannabis in their personal time?

As a general rule, employers cannot usually dictate what an employee does in their off hours. The question is whether or not those activities have a connection to the workplace. And so what we're looking at in these cases is whether or not a person is actually impaired at the point when they're coming into work.

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The challenge with these employer policies is that the science is very much not settled on this questionand impairment is not readily testable in the workplace yet. And so what we're seeing is that we have a range of decisions and a range of studies indicating different levels of THC associated with impairment, different time periods connected to impairment. So it's very difficult to dictate a particular time after which you're safe to go to work.

Some of the science says 28 days you might still have some in your system. Does some of the science say you always have some lingering effects, which might be what the airlines are relying on?

Health Canada says that in the normal course a person can expect to experience the effects of cannabis after 24 hours after the use of cannabis. The challenge comes when a person is a regular user of cannabis in those situations. You can see people will build up levels of THC in their system, and whether or not that actually means that they're impaired is a different question ... And so it depends on the person.

And then there are also studies looking at how cannabis affects someone in different circumstances, depending on, for example, the barometric pressure. And so you have some questions around people who are on airplanes, people in submarines, whether or not cannabis is actually impacting them differently.

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So with the science unclearnow, say your employer accuses you of being high on the job. What do they have to do to prove that? Can they test you, do you have grounds for an appeal, unless somebody has actually seen you smoking a joint?

It depends on the nature of your workplace.So unionized workplaces have different rules ... But as a general rule, employers are not usually allowed to have randomized drug testing, except in very narrow circumstances. So you're looking at either testing in the case of reasonable grounds, where for example someone's maybe detected a smell of cannabis or something of that nature, and then you have post-incident or post-accident testing.

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And so from my point of view, representing employees and unions, I think our advice is that you are better off as the individual to abstain from cannabis, really, at this stage, where there's so much unknown. Because if there is an accident and you're in a safety-sensitive position, you should expect to be tested.

And it may well be that at the end of the day, depending on your workplace, you may have opportunities to challenge that ... and the testing might not be justified, and if you have a level of THC in your system, that might not necessarily indicate that you're impaired.

But unless you as an individual are ready to face essentially being a test case to try those issues, you're probably better off making sure that you're able to say there's no THC in your system and you don't have to face trying to explain after the fact that you weren't impaired despite some level of THC in your system.

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If your employer hasn't made explicit what the rules are around marijuana, what should you go with?

Well, there's certainly no harm in initiating a discussion in your workplace about what the rules are. But certainly I would say you are, at this stage, better to err on the side of caution, especially given the new criminal driving offences around drug impairment. If you're in a position that requires you to use a vehicle in the course of your work, the new levels are very, very low on the criminal side. And so that's the safest bet, unfortunately at this point, is to advise, I think, to abstain.