Wallace v Kam

The High Court of Australia considered a claim in negligence brought by Mr Wallace against Dr Kam, a medical practitioner. Mr Wallace alleged that Dr Kam failed to adequately warn him of material risks associated with a surgical procedure, leading to his injury. The central dispute concerned whether the alleged failures to warn constituted a legally relevant cause of the injury that Mr Wallace sustained.

The High Court was required to determine two key legal issues. First, whether Dr Kam's failure to warn Mr Wallace of two distinct material risks inherent in the surgical procedure was a necessary condition of the injury caused by the risk that eventuated, applying the "but for" test of factual causation. Second, the Court had to consider whether it was appropriate for the scope of Dr Kam's liability to extend to the injury that Mr Wallace suffered, having regard to the nature of the risks and Mr Wallace's hypothetical choices.

The Court reasoned that the two risks, neurapraxia and paralysis, were distinct. Mr Wallace had indicated he would have undergone the surgery if warned only of the risk of neurapraxia, but would not have proceeded if warned of both risks. The Court held that because Mr Wallace would have accepted the risk of neurapraxia and would have undergone the surgery even if warned of that risk alone, the failure to warn of the risk of paralysis could not be the legal cause of the neurapraxia that eventuated. The Court applied principles of causation in negligence, distinguishing between factual causation and the scope of liability.

The appeal was dismissed with costs.