Confusion continues about causation test in medical malpractice cases

Getting rid of the ‘but for’ language could create greater certainty

Confusion continues about causation test in medical malpractice cases
Paul Harte

“But for” language is behind much of the confusion surrounding the causation analysis in medical malpractice cases, particularly those involving delayed diagnosis allegations, says a veteran practitioner.

“‘But for’ is meant to encapsulate an event that causes or contributes to the harm,” says Paul Harte of Harte Law in Richmond Hill, Ontario. “But juries get confused when they hear that phrase, especially when there’s more than one contributing cause and they hear only the ‘but for’ phrase.”

With plaintiffs having lost four out of the last five medical malpractice trials heard in Ontario that involved delayed diagnosis, the confusion may be creating an access to justice issue.

“It’s getting hard to find a lawyer to take on a case where there has clearly been negligence, but it’s not clear that the negligence is the sole cause of the harm,” he says. “That’s especially so in delayed diagnosis cases, where there’s no doubt that the treatment should have started earlier, but it’s not clear whether the delay caused the harm or what part of the harm.”

Harte, who represented the appellants involved in the April decision of the Ontario Court of Appeal in White v. St. Joseph’s Hospital (Hamilton), says the case demonstrates the challenges where both negligent and non-negligent causes intertwine.

The case arose when Paul White suffered a bowel leak that was not detected for some time after routine surgery. The leak was a rare but well recognized risk.  The plaintiff alleged that the hospital and nurses were negligent for the delayed diagnosis of the risk.

White suffered from septic shock as a result of the leak. It caused White to have a longer than usual hospital stay, including some time in the intensive care unit. He also required remedial surgery. An expert, however, testified that “most of Mr. White’s outcome was unavoidable.”

The trial judge found that the nurses and the hospital had met the standard of care in monitoring and reporting changes in the plaintiff’s status and the administration of antibiotics. She also found that the outcome would have been the same whether there was negligence or not.

In upholding the trial judge, the Court of Appeal did make it clear that the “normative test” for causation was whether the delay “caused or contributed” (words found in the Negligence Act) to the harm. This test, moreover, was “embodied in the ‘but for’ test prescribed by the Supreme Court in Clements v. Clements.”

“In other words,” the court added, “‘but for’ the alleged delay would the plaintiff have suffered the unfavourable outcome?”

While some lawyers suggest that the Court of Appeal judgment in White favours the “cause or contribute” language over the phrase “but for” in the causation analysis, this last sentence leaves little doubt that “but for” is not fatal.

And while that may be OK for judges — although the continuing professed confusion over the causation instructions from Clements throws even that proposition into doubt — it certainly, as Harte maintains, leaves room for confusion and prejudice to plaintiffs on the part of juries.

“Nobody says ‘But for my car’s flat tire, I’m late,’ because that’s inconsistent with plain language,” Harte notes. “They say, “I’m late because I had a flat tire”, and courts should approach causation in the same way.”

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