In the recent case of Benhaim v. St-Germain (2016 SCC 48), the Supreme Court of Canada clarified that in medical negligence cases in which the defendant’s negligence is alleged to have undermined the plaintiff’s ability to prove causation, and where the plaintiff adduces at least some evidence of causation, an adverse inference of causation may be drawn by the trial judge, but is not mandatory.

This sad case stemmed from the death of Marc Émond from lung cancer at the age of 47. After a November 2005 physical, Mr. Émond was sent by his physician to have a chest x-ray, which revealed an opacity in Mr. Émond’s right lung. It was not until Mr. Émond’s physical and x-ray in December 2006, revealing that the opacity had grown, that his physicians suspected the lesion in Mr. Émond’s chest may be cancerous. Shortly thereafter, it was concluded that Mr. Émond had stage IV terminal lung cancer, despite a lack of symptoms. He passed away in June 2008.

Mr. Émond’s partner, Cathie St-Germain, brought an action against the doctors claiming that they were negligent in failing to promptly diagnose Mr. Émond’s lung cancer, causing his death.

Lower Court Decisions

At the trial level (2011 QCCS 4755), the Quebec Superior Court held that Émond’s physicians were negligent in failing to conduct a more thorough investigation of Mr. Émond’s health after the initial x-ray in November 2005. That finding was not contested on appeal. However, the trial judge concluded that the physicians’ faults had not caused Mr. Émond’s death.

She assessed the dilemma posed by the defendants’ negligence, in that the lack of investigation immediately after the first x-ray negatively affected the plaintiff’s ability to prove that the lung cancer was only at an early stage at that point. The court recognized that this factor allows the court to draw an adverse inference of causation against the defendants. However, the trial judge decided to not to do so, and instead favoured the defendants’ evidence.

On appeal (2014 QCCA 2207), the majority of the Quebec Court of Appeal found that the trial judge made an error of law in not drawing an adverse inference of causation. According to the appellate court, the Supreme Court’s decision in Snell v Farrell ([1990] 2 SCR 311) established that where the defendant’s negligence undermines the plaintiff’s ability to prove causation, the trier of fact is required to draw an adverse inference. If this is the situation, the plaintiff need only provide some evidence demonstrating causation and the adverse inference then places the burden on the defendant to rebut the inference of causation.

The Court of Appeal held that the plaintiff did provide some affirmative evidence of causation and therefore that the adverse inference of causation applied. The trial decision was overturned and the doctors were found to have caused Mr. Émond’s death.

The Supreme Court’s recent decision (2016 SCC 48) to overturn the Quebec Court of Appeal’s finding has brought some clarity to the issue of causation where a defendant’s negligence undermines the plaintiff’s ability to prove causation. At para. 42, Wagner J. writing for the majority of the Supreme Court, determined that the Court of Appeal misstated the law as described in Snell:

[I]n such circumstances, an adverse inference of causation may discharge the plaintiff’s burden of proving causation. Those circumstances do not trigger such an inference. Whether an inference of causation is warranted, and how it is to be weighed against the evidence, are matter for the trier of fact. Here, the trial judge’s reasons show that she did not draw that inference, although she was aware that it was available (para. 100). That conclusion is a question of fact and deserves deference from a court of appeal

The Supreme Court went on to state that trial judges must be afforded substantial deference to evaluate all of the evidence to determine if an adverse inference is warranted. The alternative interpretation of requiring an adverse inference, argued by the Court of Appeal, would reverse the burden of proof and have the effect of creating a “novel legal rule governing presumptions.” Ultimately, a majority for the Supreme Court found that no palpable and overriding error was committed by the trial judge, and that her finding that the plaintiffs had not discharged their burden of establishing causation was upheld.

This case is important as it clarifies that professional negligence alleged to have interfered with a plaintiff’s ability to prove causation does not automatically necessitate an adverse inference of causation – it is in the discretion of the trial judge whether to draw such an inference, and the trial judge’s decision on that point is entitled to deference.