Canada: Medical Cannabis And Safety-Sensitive Jobs: Where Can Employers Draw The Line?

Last Updated: April 29 2019
Article by Andrew N. Vey

Much legal ink has been spilled over the past year about the impact of cannabis legalization on the workplace (see our overview here). At the end of the day, however, the basic rules of the game have not changed. Employees still cannot expect to attend at work while intoxicated. Employers can still insist on sobriety in the workplace. And safety-concerns regarding how to structure operations remain a foremost consideration in any workplace (and in fact are mandated by operation of the Occupational Health and Safety Act).

Where the mixture of cannabis and employment becomes complex, however, is when its utilization for medical treatment enters the picture. Unlike alcohol, both employers and the medical community are still struggling to identify an effective means of testing for cannabis impairment.

This raises an interesting question: where an employee in a safety-sensitive position is prescribed medical cannabis, what is an employer required to do?

The Lower Churchill Case

A recent decision from Newfoundland and Labrador provides a great deal of insight with respect to medical cannabis use and safety-sensitive positions: International Brotherhood of Electrical Workers, Local 1620 v. Lower Churchill Transmission Construction Employers' Association Inc.2019 NLSC 48.

Lower Churchill involved a worker employed at Muskrat Falls in Labrador, one of the largest infrastructure projects in the province's history. The worker suffered from chronic pain due to Crohn's disease and osteoarthritis. He was prescribed medical cannabis for pain management after exhausting all conventional forms of treatment. The worker would consume about 1.5 grams of cannabis (by means of vaporization) each evening after working hours.

Interestingly, the worker was never documented to have been impaired on the job due to his medical cannabis usage. He had in fact worked without incident in a safety-sensitive job while consuming medical cannabis for a period of several months in 2016 (due to a reporting error, the worker's voluntary disclosure of drug use never made it past his direct supervisor). The dispute between the parties only arose after the worker was later laid-off, applied for a new safety-sensitive role, and the question of his medical cannabis use was brought to management's attention.

The employer refused to re-hire the worker, asserting that an undue hardship would result due to the possible risk of impairment in a safety-sensitive position. The matter then advanced to arbitration between the employer and the worker's union.

Round One: Arbitration

Both sides led medical evidence at the arbitration with respect to the effect of the worker's cannabis use, with the following key points being adduced:

  • Cannabis can impair the ability of a worker to function safely in a safety-sensitive workplace;

  • Impairment can last up to 24 hours after use;

  • The impairing effects may not be known to the user; and

  • There was no available means or method to accurately test impairment from cannabis use in the workplace.

It was this last point, the lack of a means to accurately test for impairment, that proved decisive at the arbitration. Indeed, the arbitrator concluded:

The safety hazard that would be introduced into the workplace here by residual impairment arising from the Grievor's daily evening use of cannabis products could not be ameliorated by remedial or monitoring processes. Consequently, undue hardship, in terms of unacceptable increased safety risk, would result to the Employer if it put the Grievor to work. As previously stated, if the Employer cannot measure impairment, it cannot manage risk. [emphasis added]

Round Two: Judicial Review

Unhappy with their results at arbitration, the worker and his union sought judicial review.

Yet Justice Boone, for the Newfoundland and Labrador Supreme Court, confirmed the decision of the arbitrator and sided with the employer.

In reviewing the matter, Justice Boone wrote:

I find that the Arbitrator accurately identified the issue before him...He found that the duty to accommodate did not extend to a requirement that the Employer accept a risk resulting from the possibility of impairment. He concluded that the evidence of possible impairment adduced by the Employer (and not contradicted by the Grievor's treating physician who conceded the possibility of residual impairment beyond the initial four hours from use) met its onus to demonstrate undue hardship which displaced its acknowledged duty to accommodate. [emphasis added]

Lessons Learned

As the facts of Lower Churchill demonstrate, determining the scope of accommodation required for medical cannabis users in safety-sensitive positions is a heavily-fact driven exercise. There will often be competing medical evidence at hand and the science with respect to the potential for cannabis related impairment remains unsettled.

For employers with safety-sensitive work, it is imperative to keep up to date on the latest testing tools and evidence with respect to medical cannabis impairment. Had there been a reliable means of measuring impairment available to the employer in Lower Churchill, a very different outcome may have resulted.

Employees who are prescribed medical cannabis should likewise be cognizant that its usage may have an impact on their ability to work. As such, prompt disclosure to the employer is always recommended, as is active participation in the accommodation process with the aim of identifying potential resolutions. Lower Churchill represents somewhat of an extreme case, as there were no non-safety-sensitive jobs available in Muskrat Falls and the employee had no alternative means of medical treatment. Such will not be the case for every worker in every workplace, meaning that only rarely will there be no accommodations of any kind possible.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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