Duty to Warn and Causation: Wallace v Kam

By Professor Loane Skene

Wallace v Kam Case Page

The recent case of Wallace v Kam [2013] HCA 19, a unanimous judgment of the High Court of Australia, continues a trend of a rigorous application of the principles of causation in duty to warn cases within the context of medical negligence. While emphasising that patients have a legal right to make their own medical decisions, and that doctors have a legal duty to inform patients about material risks of a proposed treatment (as stated in Rogers v Whitaker [1992] HCA 58) the judgment calls for more careful scrutiny of whether doctors should be held responsible for the patient’s injury or loss in certain duty to warn cases.

The judgment also answers a vital question about causation. If a doctor negligently does not inform a patient about two or more material risks of a treatment, is the patient entitled to compensation if he or she would have agreed to take the risk that materialised, but not a risk that should have been mentioned but did not materialise? The court held that the doctor would not be liable. The patient’s claim could only succeed if the doctor negligently failed to mention a risk that the patient would not have been prepared to accept; and that risk materialised. The patient could not succeed only by satisfying the court that the patient would not have agreed to the treatment if properly informed of the other risk; that is, but for the doctor’s negligence in not disclosing the other risk, the patient would not have had the treatment and suffered the injury. Proof of that matter might establish factual causation but not that the doctor should be held responsible (‘scope of liability’). Continue reading