In Saadati v. Moorhead, 2017 SCC 28, the Supreme Court of Canada recently lowered the standard of proof for a mental injury. In Saadati, the plaintiff was injured in five motor vehicle accidents. The second accident was the subject accident of the litigation. The plaintiff only suffered physical injuries from the first accident. He suffered mental injuries from the second, third, fourth, and fifth. After the fifth accident, the plaintiff was ruled incompetent. As a result, his friends and family were allowed to testify at trial for the second accident. There was a report from the psychiatrist that the plaintiff suffered a mental disorder after the third accident.

As a result, the trial judge found there was no physical injury, brain injury, or exacerbation of pre-existing conditions as a result of the second accident. However, the court found the accident caused the plaintiff's "personality change and cognitive difficulties" based on the testimony of his family and friends. The trial judge found there were mental injuries suffered from the second accident that were recoverable despite no expert opinion or diagnosis. The defendant appealed because there was no recognized psychological injury diagnosed.

The court of appeal overturned the decision from the court below. They said there was no mental injury proven, and the trial judge was not provided with any authority or evidence to reach its conclusion absent an expert diagnosis. The plaintiff appealed to the SCC.

The SCC allowed the appeal and found expert opinion was not required to issue a damages award for a psychological injury. The court ruled the DSM and other recognized standards for diagnosis were legally irrelevant. Instead, the focus was on harm. The court will award damages for a mental injury if the plaintiff can show a serious and prolonged disturbance above ordinary annoyance, anxiety, and fear. Factors include but are not limited to:

  • How seriously an individual's participation in daily life/cognitive functions are impaired;
  • The length of the impairment; and
  • The nature and effect of any treatment.

It appears the courts have made it easier for plaintiffs to prove mental injuries.

However, the court did warn that if plaintiffs do not adduce relevant expert evidence, they risk an adverse finding in favour of a reduced quantum. Nonetheless, it appears the SCC has lowered the standard for proving a mental injury since neither expert opinion nor a formal diagnosis for a recognized psychological injury is required.

It appears the courts have made it easier for plaintiffs to prove mental injuries. They can now rely on testimony from friends and family if they are deemed incompetent from their mental injury. It also appears that plaintiffs are no longer required to provide expert opinion and evidence of a formal diagnosis recognized under the DSM or other standards.

Given the court warned plaintiffs that they risk an adverse finding if they do not proffer this kind of evidence, it is prudent that defence counsel take a more active approach. During the discovery process, they should explore issues regarding the impact on the plaintiff's cognitive function and participation in daily life activities, the length of that impairment, and the nature and effect of any treatment for that impairment. Defence counsel should also seek to examine the friends and family if they are proffering evidence on behalf of an incompetent plaintiff. It is becoming easier for plaintiffs to prove mental injuries, so defence counsel need to take proactive steps to defend those claims.


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