Skip to main content

Cutting Through the Haze: Medical Marijuana in the Workplace 101

Reading Time 3 minute read


"Do" Diligence: OHS/WSIB Newsletter

Occupational health and safety [OHS] legislation across Canada requires employers to take all reasonable precautions to ensure the health and safety of their employees. Employers are also obligated by human rights legislation to accommodate disabled employees up to the point of undue hardship. Often, these legal obligations are triggered in isolation. However, there are occasions when the obligations are triggered simultaneously – such as when an employee in a safety-sensitive position seeks accommodation due to disability. When this happens, an employer must assess its accommodation obligations, while also ensuring that it protects the health and safety of the employee and any other involved parties. This can be tricky, particularly where an employee in a safety-sensitive position has significant restrictions or is required to take a potentially impairing medication. Employer concerns about these 'tricky cases' have reached a fevered pitch in recent years when it comes to the issue of medical marijuana in the workplace.


Since 2014, the Canadian government has allowed patients to access medical marijuana directly through their doctors, who can issue prescriptions for it. In 2012, the number of Canadians authorized to possess medical marijuana was 28,115. That number is expected to grow to 450,000 in the next ten years. While these statistics may alarm employers, it is important to remember that despite the legality of the use of marijuana for certain medical purposes, nothing has changed in terms of the legal obligations that employees owe to their employers. In other words, employees still do not have a right to be impaired in the workplace where their impairment may endanger their own health and safety or that of others. 

Recent Legal Decision

A recent British Columbia Human Rights Tribunal case is perhaps best illustrative of this point. In French v. Selkin Logging[1], a heavy machine operator working for a logging company used marijuana to manage his cancer-related pain. However, he did not inform his employer he was using marijuana for this purpose, nor did he have a proper prescription for the drug. When the employer caught him smoking marijuana and he refused to stop, it terminated his employment pursuant to its zero-tolerance drug and alcohol policy. The Tribunal concluded that the termination was non-discriminatory because the employee was not legitimately in the possession and use of marijuana and did not inform his employer he was using a potentially impairing substance while performing safety-sensitive work.

Best Practices

When it comes to medical marijuana in the workplace, it's important that workplace parties not get distracted about the source of the potential impairment and instead treat the issue in the same way as they would any other potentially impairing prescription medication. What does that mean? 

First, it means that employers should double-check their existing 'drug and alcohol' or 'fitness for duty' policies to ensure that they extend to the use of medical marijuana by explicitly stating that the policy applies to both over-the-counter and illegal drugs. 

Second, it means that workplace parties must follow the same accommodation process as they would with any other doctor-prescribed medication. That is:

  • Employees must inform their employers that they have a prescription for medical marijuana and must be prepared to provide a copy of the prescription;
  • Employers are entitled to ask employees to provide supplemental medical information as to any limitations or restrictions applicable to an employee's job duties as a result of the use of medical marijuana; and
  • Employers must consider and evaluate each case individually in terms of whether and how they can accommodate an individual employee – in every case considering the individual employee's particular job duties, limitations and restrictions. In other words, employers must not assume that medical marijuana will automatically impair an employee and render him or her incapable of safety performing his or her job.

[1] 2015 BCHRT 101