Government Insurance Office of NSW v Aboushadi

The Government Insurance Office of NSW (GIO) appealed a decision of the District Court of NSW concerning a claim for damages for personal injury brought by Mr Aboushadi. Mr Aboushadi had suffered a psychiatric injury, specifically post-traumatic stress disorder (PTSD), which he alleged was caused by the negligence of GIO. The core of the dispute revolved around the extent of GIO's liability for Mr Aboushadi's injuries, particularly in light of a pre-existing condition and subsequent events.

The Court of Appeal was required to determine whether the District Court had erred in its assessment of causation and damages. Specifically, the court had to consider the principles applicable when a defendant's tortious conduct aggravates a pre-existing injury or condition, and how to avoid double compensation where a subsequent event might also have caused or contributed to the injury. The central legal issue was how to apportion liability and assess damages when the plaintiff's ultimate harm was a consequence of multiple factors, including the defendant's negligence.

The Court of Appeal affirmed the principles of causation in negligence, particularly in cases involving psychiatric injury and pre-existing conditions. The court held that where a defendant's negligence causes an injury, and that injury is then aggravated by a subsequent event (whether tortious or not), the defendant is liable for the aggravation. However, the court stressed the importance of ensuring that the plaintiff is not overcompensated. The reasoning focused on the need to isolate the damage caused by the defendant's tort from damage that would have occurred irrespective of the tort, or damage caused by subsequent events. The court applied established principles to determine the extent to which the defendant's conduct had caused or aggravated the plaintiff's PTSD, ensuring that compensation was awarded only for the attributable portion of the harm.

The appeal was dismissed, and GIO was ordered to pay Mr Aboushadi's costs.