Ali v AAI Limited

The appeal in *Ali v AAI Limited* concerned a judicial review of a certificate issued by a medical assessor regarding the degree of permanent impairment of the plaintiff, Abbas Ibrahim Ali, following a motor vehicle accident. The plaintiff sought to challenge the certificate, which was issued under Part 3.4 of the *Motor Accidents Compensation Act 1999* (NSW), arguing that the medical assessor had failed to properly consider relevant material and had taken irrelevant considerations into account. The primary dispute revolved around the scope of the statutory duty to provide reasons for the assessor's decision and the extent to which reference to a large volume of supplied material satisfied this obligation.

The court was required to determine several key legal issues. Firstly, it had to consider the scope of the statutory duty imposed on a medical assessor to give reasons for their certificate, particularly in relation to the extent to which reference to a large volume of material supplied by the parties constituted adequate reasons. Secondly, the court examined the obligation to consider matters identified by the statute and material supplied by the parties, and conversely, the prohibition against considering irrelevant material. Finally, the court addressed whether "unreliable" evidence was to be completely disregarded by the medical assessor. The legal status of the Motor Accident Authority Guidelines and whether a breach of these Guidelines amounted to judicially reviewable error were also central to the determination.

The Court of Appeal allowed the appeal, setting aside the orders made in the Common Law Division. The court found that the medical assessor's reasons were inadequate and that the assessor had failed to properly consider the material before them. The court held that a mere reference to a large volume of documents was not sufficient to discharge the duty to give reasons, and that the assessor was obliged to engage with the substance of the evidence. The court also determined that the Motor Accident Authority Guidelines did not have the force of delegated legislation, but that a breach of the Guidelines could nonetheless constitute a ground for judicial review if it indicated an error of law. Consequently, the summons filed by the plaintiff was dismissed, and orders were made regarding the costs of the proceedings in both the Common Law Division and the Court of Appeal.