Botany Bay City Council v Rethmann Australia Environmental Services Pty Limited

The Court of Appeal of New South Wales heard an appeal concerning allegations of apprehended bias and procedural unfairness in proceedings before the Land and Environment Court. The appellant, Botany Bay City Council, contended that the primary judge had improperly intervened in the questioning of expert witnesses, thereby taking the case out of the hands of the parties and expressing a premature final opinion. The respondent was Rethmann Australia Environmental Services Pty Limited.

The central legal issues before the Court of Appeal were whether the primary judge’s conduct in questioning the experts amounted to a denial of procedural fairness, and whether this conduct gave rise to a reasonable apprehension of bias, warranting the judge's disqualification. Specifically, the Council argued that the judge’s questioning, particularly in light of conflicting expert evidence, indicated a pre-judgment of the issues and an unfair preference for one expert's opinion over another.

The Court of Appeal found no basis for the allegations of apprehended bias or procedural unfairness. Their Honours reasoned that the primary judge’s questioning of the experts was a legitimate exercise of the court’s power to clarify complex technical evidence, particularly where there was a significant divergence between the parties' expert witnesses. The judge’s engagement was aimed at understanding the conflicting methodologies and the basis for the experts’ opinions, rather than substituting the court’s own opinion for that of the experts. The refusal to admit new material late in the proceedings was also found to be a proper exercise of judicial discretion, not indicative of bias. The court emphasised that the judge’s role was to weigh all the evidence presented, including that of any court-appointed independent expert, against the evidence adduced by the parties.

The appeal was dismissed with costs.