Causation of injury is often a contentious issue in medical negligence claims. Usually the question is which of a number of possible causes gave rise to the harm complained of, or whether one of those causes ought to result in legal liability. 

A recent decision of the Victorian Court of Appeal, Powney v Kerang and District Health, 1  was a variation on this theme. The issue for the Court was whether, despite the fact that the precise cause of injury could not be established, the Court could ‘bridge the evidentiary gap’ and find that a hospital’s negligence was indeed the relevant cause of the patient’s injury.


The plaintiff attended hospital for nasal surgery. He experienced post-operative pain and was given a pethidine injection. A few days later he developed a severe infection in his arm at the injection site. The plaintiff claimed that the injection was administered negligently in that the needle had been left uncapped and was unsterile. He alleged that the resulting infection left him with a significant permanent injury of his left arm and an associated psychiatric condition.


The plaintiff had no memory of his stay in hospital, but relied on lay evidence of his (then) 12 year old daughter and 16 year old niece who both alleged that they recalled seeing an uncapped needle in a kidney dish prior to the nurse administering the injection. 

The hospital called the nurse in question to give evidence. Whilst she did not recall the plaintiff specifically, she gave evidence of her usual practice when administering injections, which was to keep the needle cap on until it was administered. Both parties called infectious disease experts to provide expert opinion in relation to the risk of infection from the administration of an uncapped needle. 

At the conclusion of evidence, the plaintiff’s counsel submitted that if the jury was not satisfied that factual causation was made out on the ‘but for’ test, it could nevertheless consider whether this was a case in which section 51(2) Wrongs Act 1958 (Vic) (Act) could be invoked. 

That section allows a bridging of an evidentiary gap in “an appropriate” case where factual causation ie whether the defendant’s negligence was a necessary condition of the occurrence of harm, cannot be established. It permits a finding that the negligence should be taken to establish factual causation. If invoked, the court must make a policy decision about whether or not responsibility for the harm should be imposed on the defendant and explain why.

The trial judge rejected this approach, limiting the jury’s deliberation to factual causation under section 51(1) of the Act. The jury found that the hospital was not negligent.


The plaintiff appealed on the grounds that the trial judge should have allowed the jury to consider section 51(2) as an alternative if factual causation was not made out. The Court of Appeal found that the trial judge’s approach was correct.

The Court explained that the rationale behind section 51(2) was to assist with cases where there was a genuine evidentiary gap in relation to how harm was caused. It is designed to address situations where there are multiple or cumulative factors that contribute to harm or cases where the state of current medical knowledge makes it impossible to prove the cause of the plaintiff’s harm. As such, the Court commented that this case, which did not involve multiple causes of harm or lack of medical knowledge, was not the type of case that would fall within the ambit of section 51(2).

The Court also ruled that it is the trial judge’s, not the jury’s, function to determine whether a case is an “appropriate” one in which to invoke section 51(2). This is because the provision requires a court to consider issues of policy.