Gett v Tabet (2009) NSWCA 76: Loss of a chance - Now a lost cause
On 9 April 2009 the NSW Court of Appeal handed down its decision in Gett v Tabet  NSW CA76. The effect of this decision is to overturn Rufo v Hosking  61 NSWLR 678 and abolish loss of a chance claims in New South Wales.
The case involved an alleged delay in diagnosis of a brain tumour in a 6 year old child who now suffers significant brain damage. It was alleged that if the defendant had have performed a CT scan on 13 January 1991 the brain tumour would have been diagnosed, treatment commenced and the plaintiff would have avoided the seizure which occurred on 14 January 1991, which contributed to his brain damage. As a result of the failure to perform a CT scan, the plaintiff lost the chance of avoiding the seizure and having a better outcome.
At First Instance
The Supreme Court determined that 25% of the plaintiff’s brain damage resulted from the seizure that was suffered on 14 January 1991. In accordance with the principle set out in Rufo v Hoskings  NSWCA 391 the plaintiff was required to prove, on the balance of probabilities, that there existed a chance of a better outcome (i.e. avoiding 25% of his brain damage) had the negligent treatment (failure to perform a CT san) not occurred and this was a chance which would have been taken.
At first instance, the Supreme Court found that the failure to perform a CT on 13 January caused the plaintiff to lose the chance of a better outcome. His Honour determined that if a CT scan was performed on 13 January, the plaintiff would have had a 40% chance of a better outcome (i.e. avoiding 25% of his brain damage).
The Court of Appeal
The Court of Appeal noted that a loss of a chance case requires the plaintiff to be compensated for an opportunity lost, not for any physical harm suffered. Even though the value of the lost opportunity may be calculated by reference to the physical harm that eventuated, the harm suffered remains a lost opportunity. This involves an expansion of the definition of harm in personal injury matters. Such an expansion is in contradiction to the NSW Civil Liability Act which specifically defines harm as including personal injury, damage to property and economic loss.
Further, Section 5E of the CLA requires that the plaintiff always bears the onus of proving, on the balance of probabilities, any fact relevant to the issue of causation. A loss of a chance case removes this onus of proof from the plaintiff who does not have to prove, on the balance of probabilities, that the injury actually suffered was caused by the negligence.
The Court of Appeal acknowledged that the principle of loss of a chance in medical negligence cases was established in Rufo, but was highly critical of this decision. The Court of Appeal stated that Rufo involved “a departure from conventional principles and in our respectful view, is plainly wrong”.
The Court of Appeal declined to follow Rufo and noted that it is for the High Court, and only the High Court, to reformulate the law of tort to permit “recovery for physical injury not shown to be caused or contributed to by a negligent party but which negligence has deprived the victim of the possibility (but not the probability) of a better outcome.”
The Court of Appeal went back to the fundamental, underlying principles of causation - that the plaintiff must prove, on the balance of probabilities that the harm suffered (that being a personal injury, damage to property or economic loss) was caused or contributed to by the negligence of the defendant.
The Court of Appeal held that the plaintiff did not prove on the balance of probabilities that the additional 25% of his brain damage was caused by the failure to perform a CT scan on 13 January.
On the basis of this decision, plaintiffs in New South Wales cannot sustain a claim for loss of a chance.
This has significant implications in all cases involving a delay in diagnosis. The implications are perhaps less significant in cases involving delay of diagnosis of cancer where statistical evidence is widely available to enable experts to opine upon prognosis and comment upon the effect of delay. In such cases, the plaintiff should be able to obtain expert evidence which will satisfy the balance of probabilities.
In other delay cases, particularly those involving rarer conditions or highly individualised conditions, it is much more difficult for a plaintiff to prove, on the balance of probabilities, that the delay in the diagnosis caused a physical injury or that earlier intervention, on the balance of probabilities, would have avoided such an injury.
Prior to this decision, loss of a chance cases were often difficult for most defendants to defend. In medical terms, it is generally stated by most plaintiff experts that anything is possible and under a loss of chance regime a simple assertion of such a possibility was enough to see the plaintiff receive an award of damages.
The Court of Appeal has clearly laid down the challenge to plaintiffs that if they seek to recover damages for loss of a chance, this is a matter which needs to be determined by the High Court.
The High Court may well conclude that policy decisions are a matter for the legislature, which would involve amending the Civil Liability Act. This course was taken by several states, including New South Wales, following the High Court’s decision in Cattanach v Melchior  HCA 38.
We recommend that any case involving a delay in diagnosis be reviewed to consider the implications of Gett.
Kylie Agland, Partner