Appeal court confirms doctors liable in medical malpractice case concerning law of informed consent

In a case concerning the law of informed consent in medical malpractice claims, the Ontario Court of Appeal has confirmed a lower court ruling that three doctors did not adequately inform a patient of the risks of a medical procedure that partly paralyzed him.

“Patients have a right to make informed decisions that involve their health care,” says Sloan Mandel, counsel for the patient and a partner at Thomson Rogers in Toronto. “Doctors, and in certain circumstances, a team of doctors, can have the obligation to ensure that adequate disclosure is made to the patient, prior to embarking upon a course of risky treatment, particularly so in cases involving non-urgent and elective intervention.”

Michael Denman sued three doctors at Toronto Western Hospital after a catastrophic brain bleed resulted from a medical procedure for which he argued the doctors had not obtained his informed consent. The injury left the 54-year-old paralyzed on the left side of his body.  

The procedure was elective and part of a multi-step treatment plan to cure an anterior ventricle malformation. Denman argued that doctors had been negligent in failing to obtain consent because neither he nor a reasonable person in his circumstances would have chosen the treatment.

“You don’t buy a train ticket to destination cure, without knowing the full cost of the ticket,” says Mandel.

The trial judge ruled that the doctors were liable for failing to obtain informed consent, and Denman was awarded $8.5 million.

The doctors appealed, arguing the judge misapplied the law of informed consent and erred in disqualifying one of their proposed experts.

When doctors fail to provide patients with adequate disclosure, they are subject to a negligence claim. While Denman was informed of each procedure he underwent, the issue in Denman v. Radovanovic, 2024 ONCA 276 was whether the consent was informed. Doctors have a duty to disclose the nature of a proposed elective treatment, its risks, and alternative options available.

Patients alleging lack of informed consent must prove the information provided was inadequate, that they would not have undergone the procedure if they had been adequately informed, and that a reasonable person in their position, who was adequately informed, would also have opted against the procedure.

The Court of Appeal rejected the doctors’ claim that the trial judge had failed to consider Denman’s personal circumstances when applying the test for informed consent and their argument that the judge erred in requiring that the doctors “provide exact statistical probabilities” in their risk assessment. The appeal court also concluded that all three judges were properly found liable, even though one did not participate in the procedure. That doctor was obligated to obtain Denman’s informed consent at the outset.

The Court of Appeal’s panel consisted of Justices Paul Rouleau, Mary Lou Benotto, and Jill Copeland, with Justice Rouleau writing the reasons. The court also rejected the doctors’ submission that the trial judge erred in refusing to recognize an expert witness they had called. The judge excluded the witness after Denman challenged him for bias, and the appeal court ruled that the appellants had not met the threshold compelling them to interfere with the decision.