South Western Sydney Local Health District v Gould

South Western Sydney Local Health District (the appellant) appealed to the Court of Appeal of New South Wales against a judgment of the primary judge who found the District liable for medical negligence. The dispute concerned the treatment of the respondent, Ms. Gould, for an injury to her thumb, specifically whether the appropriate antibiotics were administered.

The central legal issue before the Court of Appeal was whether the primary judge had erred in finding that the appellant's evidence regarding competent professional practice was "irrational" within the meaning of section 5O(2) of the *Civil Liability Act 2002* (NSW). This finding was critical because it allowed the primary judge to depart from the standard of care ordinarily established by expert evidence. The appellant argued that the primary judge's application of section 5O(2) was flawed, particularly as the concept of "irrationality" had not been pleaded or raised during the trial.

The Court of Appeal held that the primary judge had misconstrued section 5O(2) of the *Civil Liability Act 2002* (NSW). The Court found that the primary judge's assessment of the appellant's expert evidence as "irrational" was not supported by the legislative text, context, or purpose, and appeared to be based on an equation of irrationality with unreasonableness or a requirement for greater logical probative force or justification than the section mandated. Crucially, the issue of irrationality was not raised with the appellant's experts, nor was it a focus of the trial. Consequently, the Court of Appeal set aside the primary judge's finding of irrationality, upheld the defence under section 5O, and allowed the appeal.

The Court of Appeal allowed the appeal, set aside the primary judge's judgment and orders, and ordered that the proceedings be dismissed. The respondent was ordered to pay the appellant's costs at first instance and on appeal, with a certificate granted under the *Suitors’ Fund Act 1951* (NSW).