Invisible Injury: Two Canadian Supreme Court Rulings That Changed Workplace Mental Health Forever
For decades, if you wanted compensation for an injury, you needed a cast, a crutch, or a visible wound. Mental injury—stress, anxiety, and psychological distress caused by negligence—was often dismissed as subjective or simply "part of life."
In Canada, however, that all changed thanks to two powerful Supreme Court of Canada (SCC) rulings. These decisions didn't just recognize mental injury; they established it as a legally compensable harm, putting employers on notice about their duty of care for psychological safety.
1. The Foundation: Mental Injury is a Real Injury (2008)
The first landmark case, Mustapha v. Culligan of Canada Ltd. (2008), laid the essential groundwork.
Mr. Mustapha, a water delivery customer, opened a bottle of water he was about to install and saw dead flies and their remains floating inside. The experience was so distressing that he developed a major depressive disorder, phobias, and anxiety, eventually leading to the failure of his marriage and his inability to work. He sued Culligan for negligence.
The Key Takeaway: Foreseeability is Everything
The SCC ruled that if a defendant's negligent actions cause a mental injury, they can be held liable, just as they would be for a physical injury.
The legal principle established: Mental injury (not just physical injury) is a compensable form of harm in a negligence claim, provided the injury is serious and prolonged and was a reasonably foreseeable consequence of the defendant's actions.
The court ultimately found that while Mr. Mustapha's injury was genuine, his extreme reaction to the flies was not "reasonably foreseeable" by Culligan's employees. However, the ruling's lasting impact was profound: it paved the way for general duty of care claims involving psychological harm by affirming that mental injury is, legally, just as valid as physical injury.
2. Lowering the Evidentiary Bar: You Don't Need a Diagnosis (2017)
If Mustapha proved mental injury was valid, the second landmark case, Saadati v. Moorhead (2017), made it easier to prove.
Mr. Saadati was involved in a motor vehicle accident caused by Mr. Moorhead. Following the accident, Mr. Saadati began suffering from debilitating depression, anxiety, and cognitive difficulties, though he did not receive a formal diagnosis for a recognized psychiatric illness (like PTSD or Major Depressive Disorder).
The Message to the Workplace
Together, Mustapha and Saadati send an undeniable message to every Canadian employer:
Mental Harm is Legal Liability: You can be sued for negligence that leads to a serious psychological injury.
Proactive Steps are Due Diligence: The legal risk is high, meaning simply having physical safety policies isn't enough. Proactive measures (like training managers, establishing anti-bullying programs, or implementing supportive resources) are now necessary to satisfy the general duty of care and prove you took reasonable precautions against foreseeable psychological harm.
The time to treat psychological safety as secondary to physical safety is over. It is now a core component of legal due diligence.
From Legal Risk to Practical Action: The Canadian National Standard
These Supreme Court decisions establish the legal risk, but they don't tell you how to mitigate it. That's where the National Standard of Canada for Psychological Health and Safety in the Workplace comes in.
Launched in 2013, the PHS Standard is a voluntary framework and set of guidelines developed to help organizations proactively create mentally healthy workplaces. While the Standard itself is not law, it represents the recognized benchmark for due diligence in psychological safety.
When an employer faces a claim of negligence or failure to accommodate psychological injury, courts and tribunals often look to the PHS Standard. By failing to implement policies and systems outlined in the Standard (such as effective training or supportive resources), an employer struggles to prove they took "reasonable precautions" to prevent foreseeable harm.
Implementing the PHS Standard moves your organization from merely complying with the minimum requirements of OHS law to actively demonstrating the due diligence necessary to satisfy your general duty of care in the modern legal landscape.
The Message to the Workplace
The time to treat psychological safety as secondary to physical safety is over. It is now a core component of legal due diligence. The combination of SCC rulings and the PHS Standard means:
Mental Harm is Legal Liability: You can be sued for negligence that leads to a serious psychological injury.
Proactive Steps Are Due Diligence: Implementing recognized frameworks like the PHS Standard is the strongest defense against claims of negligence and failure to accommodate.
Ready to Build a Psychologically Safe Workplace?
The legal risk is clear, but the path to compliance is manageable. To understand exactly what the National Standard requires and how it applies to your organization: Read Our Blog: What is the New Canadian National Standard Psychological Health and Safety (PHS) in Canada.
