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Workers and marijuana: what builders need to know

Don Wall
Workers and marijuana: what builders need to know

The obligation of employers to ensure safety at workplaces such as construction jobsites has not changed despite increased use of medical marijuana and its possible legalization by the federal Liberal government, says a legal expert active in the field.

There is a lot of misinformation out there, said Norm Keith, a leading Canadian occupational health and safety defence lawyer and senior partner with Fasken Martineau.

The Toronto-based author of numerous workplace manuals including Alcohol & Drugs in the Canadian Workplace — An Employer’s Guide, Keith argues the federal government must take some of the blame for the "chaos" and "confusion" in the media, on the streets and in workplaces, with its "imprecise" promise that it is going to legalize marijuana, "whatever that means."

Former health minister Anne McLellan’s 102-page report for the government did nothing to clarify government intentions, he said.

As a result, construction employers are coming to him wondering what the current state of the law is, he said. Keith has an active practice in the sector and will be addressing marijuana in the workplace issues at an upcoming Ontario General Contractors Association (OGCA) symposium to be held in April.

"Forty per cent of deaths in a workplace, about a thousand here in Canada, are due to alcohol or drugs or both,"

Norm Keith

Fasken Martineau

"There is a lot of controversy about this," said Keith. "I think the longer the federal government holds out uncertainty about what the law will look like, the worse this problem will get.

"What is going on today on construction sites, when there is a smoke break, younger workers or workers that allege they have a so-called medical marijuana prescription, which does not exist, say, ‘I have a right to smoke this, you can’t stop this employer.’"

But whether an employee is using legal or illegal substances, said Keith, the obligation of the employer is clear.

"Here’s the law," he said. "An employer is prohibited from allowing the worker to do safety-sensitive work if they are under the influence of anything that would impair their fitness or duty. That is against the law, the employer would be breaking the law."

Keith rejects the term medical marijuana, saying it is more accurate to refer to an individual who has written medical authorization to use marijuana. He says employers have to be careful to check out claims by employees that they have authorization because there are a lot of fraudulent claims being made these days.

If a doctor confirms the authorization, then employers have difficult decisions to make, with both criminal code and occupational health and safety laws imposing duties.

"In the very rare case that a person can produce a medical authorization from a doctor, then the employer is faced with the difficult problem of how do they manage the risk, not only the safety risk but also the lawful risk, of them violating the criminal code potentially by permitting the person in a safety-sensitive position to smoke a drug with psychotic effects that will likely, not guarantee but likely, impair their ability to do their job properly," said Keith.

"The problem has become very common and applies to many medications that may impair the patient. The pending legalizing of marijuana will further complicate the issue."

Norm Keith

Fasken Martineau

"The advice we give is simple. If there is any change that affects fitness for work then they need to be excluded and taken out of the safety-sensitive position."

In the U.S., where Colorado and other states have legalized use of marijuana, there is a growing body of evidence on the specific effects of marijuana on worker performance.

The California Society of Addiction Medicine website reports studies have shown that marijuana slows reaction time and causes dizziness and other psychological effects that may prevent working safely, including safe operation of equipment and tools. A recent presentation to the Newfoundland and Labrador Construction Safety Association by a Canadian occupational testing advocate noted vulnerability varied between construction workers using marijuana versus alcohol.

OGCA director of government relations David Frame explained his organization’s interest in the topic: "Under the Occupational Health and Safety Act employers have the responsibility to accommodate workers with medical conditions. They also have the responsibility to determine fitness for work, i.e. is the worker physically and mentally able to perform the job safely, without putting themselves or others at risk?

"Medical marijuana requires that users are accommodated but they may not be fit for work. The problem has become very common and applies to many medications that may impair the patient. The pending legalizing of marijuana will further complicate the issue."

Keith said it is clear there will be more deaths on roadways and jobsites if the Liberals follow through on their pledge to liberalize marijuana laws.

"Forty per cent of deaths in a workplace, about a thousand here in Canada, are due to alcohol or drugs or both," he said. "It is a bad problem, and it is going to get worse if marijuana is legalized…evidence from Colorado and other states indicate that it will."

Keith noted the Canadian law on workplace drug testing places narrow limitations on the employer’s rights, following the Irving Pulp and Paper case. To test workers, the employer needs reasonable cause with objective evidence of drug or alcohol use; there has to have been a significant workplace incident; or it must be in a reinstatement or last-chance employment situation.

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