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Workplace Laws & Cannabis

A common misconception amongst employers as it relates to the upcoming legalization of cannabis is that employees will be permitted to use cannabis at work or permitted to report to work under the influence of cannabis.  However, the fact is that in anticipation of the upcoming legalization, the Ontario Government released legislation which specifically prohibits the use of cannabis in any workplace.  Furthermore, existing health and safety laws prohibit employees to be impaired at work or otherwise undertake any act which could impact on their safety or the safety of others.

Nevertheless, it is important for employers to recognize that the legalization of cannabis will have a major impact on society and consequently, workplaces.  Therefore, it is imperative that employers understand the landscape surrounding cannabis in the workplace and take steps to be prepared for the upcoming changes.

1. Health and Safety 

  • Employees who are impaired by alcohol, drugs or other substances which could endanger themselves or coworkers must not enter or remain at the workplace. 
  • Employers have a general responsibility to provide a safe workplace, and this extends to ensuring that employees who are impaired are removed from the workplace.

2. Human Rights 

  • Employees who have an addiction to recreational cannabis must be accommodated to the point of undue hardship.  The accommodation is means employers must first attempt to get employees to undergo treatment to overcome the addiction before they can discipline or terminate employees for being impaired at the workplace. 
  • Employees who need to use medicinal cannabis must be accommodated to the point of undue hardship.
    • Employees requesting accommodation must provide medical documentation confirming the need for medicinal cannabis.​
    • Employers must seek out medical information to determine whether employees can safely perform his/her duties while consuming medicinal cannabis.  If the answer is ‘no’, then employers are not likely required to permit cannabis use.  If the answer is ‘yes’, then employers must investigate whether cannabis can be consumed in a manner without impacting on the health and safety of others (e.g. ingesting cannabis instead of smoking it, adjusting an employee’s schedule around their cannabis use). 
  • Employees must participate in the accommodation process.  This involves disclosing their use of cannabis, providing medical documentation authorizing cannabis use or confirming an addiction, and not insisting that accommodation take the specific form they desire.

3. Privacy 

  • Employers cannot expect employees to report their off-duty consumption of cannabis unless it relates to health and safety, human rights, or work performance issues. 
  • Drug testing is justified if employees have been involved in a work-related accident and employers expect that drug use may have been involved. Drug testing is also likely permissible when employees work in a safety-sensitive position. 
  • Drug testing results should only be disclosed to other staff members on a need-to-know basis so as to protect the privacy of employees.

In light of the foregoing issues, employers should ensure they have a drug and alcohol policy in place which addresses the following: 

  • Drug (including recreational cannabis) and alcohol use is strictly prohibited in the workplace.  
  • Employees who have a drug or alcohol disability will be accommodated up to the point of undue hardship.  Employees must participate in the accommodation process.
  • Outline the terms under which medication (including medicinal cannabis) use is permitted at the workplace.​
  • Employees have an obligation to notify of their use of medication (including medicinal cannabis) and to report if they are impaired by drugs or alcohol at work.​  

In addition, managers and employees must be trained on drug, alcohol and medication use in the workplace.  

The legalization of cannabis does not fundamentally alter workplace laws.  Recreational cannabis use is similar to alcohol use, whereas the use of medicinal cannabis is similar to the use of any prescription drug which has the ability to impact on health and safety in the workplace.  Nevertheless, employers should take this opportunity to update their existing policies and provide refresher training since employees will be using cannabis more openly and freely after October 17th. 

If you have any questions relating to this article or wish to discuss your particular concerns, you may reach the author at or (905) 276-0408.

This article is provided for general information purposes and should not be considered a legal opinion. Clients are advised to obtain legal advice on their specific situations.

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