The Standard of Specialists

In this important case, the Supreme Court of Canada held that a specialist owes a duty to conduct their practice to the same standard as a prudent and diligent doctor in the same circumstances.


The plaintiff, Ter Neuzen, was infected with HIV during an insemination procedure conducted by the defendant, Dr. Korn. The patient sued Dr. Korn for negligence and alternatively claimed there was a breach of warranty under the Sales of Goods Act and the common law. 

The trial judge stated that the jury was open to finding the respondent negligent on the basis that Korn failed to comply with the standard medical practice at that time and alternatively, they may find the approved practice itself was negligent. He also instructed the jury that they must consider if there was a warranty of fitness and merchantability at common law, but any common law warrant would amount to the same as negligence. 

The jury found the defendant guilty of negligence and assessed general damages. The Court of Appeal set the verdict aside, ordering a new trial on the issue of liability and damages. As for the negligence claim, the court distinguished between two aspects of Dr. Korn’s practice. First, the conduct of the procedure reflected the current state of knowledge regarding the risk of transmitting HIV involved in the procedure. Second, the screening and follow-up of donors. 

Ultimately, the court found it impossible to determine if the jury found the doctor negligent on the first or second aspect of his practice. Based on the evidence, the jury could not find that the respondent ought to have known of the risk of HIV by artificial insemination. The verdict could not stand.

The plaintiff appealed and the case was brought before the Supreme Court of Canada. The Supreme Court stated that,

“In the case of a specialist, such as a gynaecologist and obstetrician, the doctor’s behaviour must be assessed in light of the conduct of other ordinary specialists, who possess a reasonable level of knowledge, competence, and skill expected of professionals in Canada, in that field.  The conduct of physicians must be judged in the light of the knowledge that ought to have been reasonably possessed at the time of the alleged act of negligence.”

The Court then found that the trial judge did err in his instruction and upheld the Court of Appeal’s decision. At the time, the risk of contracting HIV from an AI procedure was uncertain, not becoming a known risk until after the incident had occurred. 

Read the full case here.

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From CanLii