A disability support worker was hit in the side of the head by a soccer ball kicked by a 13 year old ‘troubled’ boy (JR) who was known to have behavioural disorders and educational needs. Wilson J found because of JR’s condition and the absence of JR’s carer there was a breach of the duty of care. The plaintiff claimed the striking of the ball caused a cervical injury to the C5 by compressing the nerve root. Dr Kahler performed a cervical discectomy and interbody fusion, with decompression of the exiting right C5 nerve.
Causation was in issue – both as to the cause of the incident and the injury claimed. The injury occurred on 18 January 2006 and hence was determined at common law. Wilson J found against the plaintiff in relation to both. The first being a legal analyse of the categorisation of the risk which culminated in the harm, the second, a factual finding as to the cause of the nerve root compression injury alleged.
Margaret Wilson J
 Causation is a question of fact on which the plaintiff bears the onus of proof. She must persuade the Court on the balance of probabilities that the failure to supervise JR was a cause of her being struck and injured.
 In March v E & MH Stramere Pty Ltd the High Court adopted “the common sense” approach to causation. Whether a particular act or omission caused a particular occurrence is to be determined “by applying common sense to the facts” of the case. The High Court held that the “but for” test was neither a comprehensive nor an exclusive test of causation in tort: As Gummow and Kirby JJ observed in Tame v New South Wales
“…value judgments and policy considerations necessarily intrude.”
 The “but for” test retains a role as a negative criterion of liability in tort. Beazley JA, writing extra-judicially in Fleming’s The Law of Torts, explained its role when she said –
“The ‘but for’ test
[9.40] The ‘but for’ (sine qua non) test of causation postulates that the defendant’s conduct is a cause of the plaintiff’s harm if such harm would not have occurred without, or ‘but for’ it. The ‘but for’ test thus operates as a negative criterion of causation that eliminates factors which made no difference to the outcome. Thus the causal inquiry is directed to the wrongdoer’s breach of duty, and not conduct, which caused harm but which was not wrongful. It is not all negligent conduct that results in legal liability. The defendant’s conduct is not a legal cause if the harm would have happened in any event, fault or no fault; for example, a doctor’s delay in attending a patient is causally irrelevant if the patient would have suffered the same damage in any event.
When the ‘but for’ test yields a positive answer, the conduct qualifies as a possible, though by no means necessarily, sufficient cause for legal purposes. To be a sufficient cause, the wrongful conduct must pass an additional test as a ‘proximate’ or ‘legal’ cause. In other words, ‘but for’ is a necessary but not always a sufficient condition of legal responsibility.
The objection is sometimes raised that the question is not what might have happened ‘but for’ the negligent conduct, but what did happen. This objection fails to understand the role of the ‘but for’ test as a negative criterion of causation. It is by comparing what has happened with would have happened ‘but for’ the negligent conduct that enables the decision-maker to determine the effect of the negligent conduct and thus its causal relevance. This is a central notion in tort law: that injury could have been avoided by acting differently.”
 The present state of the authorities was summarised by Kiefel J in Tabet v Gett, where her Honour said –
“ The common law requires proof, by the person seeking compensation, that the negligent act or omission caused the loss or injury constituting the damage. All that is necessary is that, according to the course of common experience, the more probable inference appearing from the evidence is that a defendant’s negligence caused the injury or harm. ‘More probable’ means no more than that, upon a balance of probabilities, such an inference might reasonably be considered to have some greater degree of likelihood; it does not require certainty.
 The ‘but for’ test is regarded as having an important role in the resolution of the issue of causation, although more as a negative criterion than as a comprehensive test. The resolution of the question of causation has been said to involve the common sense idea of one matter being the cause of another. But it is also necessary to understand the purpose for making an inquiry about causation and that may require value judgments and policy choices.
 Once causation is proved to the general standard, the common law treats what is shown to have occurred as certain. The purpose of proof at law, unlike science or philosophy, is to apportion legal responsibility. That requires the courts, by a judgment, to ‘reduce to legal certainty questions to which no other conclusive answer can be given’. The result of this approach is that when loss or damage is proved to have been caused by a defendant’s act or omission, a plaintiff records the entire loss (the ‘all or nothing’ rule).”
 It was for the plaintiff to prove that the failure to supervise JR materially caused her injury. She had to prove that the failure to supervise gave rise to a risk, or an added risk, that she would be injured, and that that risk eventuated.
 In Bennett v Minister of Community Welfare Gaudron J said –
“… generally speaking, if an injury occurs within an area of foreseeable risk, then, in the absence of evidence that the breach had no effect, or that the injury would have occurred even if the duty had been performed, it will be taken that the breach of the common law duty caused or materially contributed to the injury…”
As Gummow, Hayne and Heydon JJ observed in Roads and Traffic Authority v Royal, her Honour’s reasoning proceeded on the assumption that a chain of causation had been established.
 Counsel for the plaintiff submitted –
“… once a Plaintiff demonstrates that a breach of duty has occurred, followed by injury within the area of foreseeable risk, a prima facie casual connection will be established and the Defendant has an evidential burden to adduce evidence that the breach had no effect or that the injury would have occurred even if the duty had been performed. If there is evidence sufficient to displace the prima facie case, it remains for the Plaintiff upon the whole of the evidence to satisfy the tribunal of fact that the injury was caused by or materially contributed to by the Defendant’s negligence.”
 For present purposes, I shall assume that to be a correct statement of the law. Importantly, it acknowledges the need to establish “injury within the area of foreseeable risk”.
 What was the risk, or added risk, arising from the absence of supervision? It was that, given the sort of child he was, JR was more likely to engage in anti-social behaviour, or that there would be an escalation in any inappropriate and potentially anti-social behaviour on his part.
 The Court may draw inferences only from facts which it finds to be proved to the requisite standard.
 There is a dearth of evidence about JR’s behaviour at the time he kicked the ball. There is no evidence of anti-social behaviour, or of escalation in misbehaviour. There is no evidence that in kicking the ball he deliberately aimed at the plaintiff. There is no evidence that he acted recklessly in kicking the ball: he may well have simply made a miscalculation. In short, there is no evidence that the identified risk eventuated.
 For these reasons, the plaintiff has not discharged her onus of proving that breach of duty for which the defendant is responsible was a material cause of the harm she suffered. Her claim should be dismissed.
 On the evidence, the C5 nerve root compression clearly resulted from degenerative changes in the cervical spine rather than from the soccer ball striking the plaintiff’s head. Such nerve root compression develops over a prolonged period. It may remain asymptomatic, or it may become symptomatic quite suddenly, even in the absence of trauma.
 The real issue for determination emerged during oral submissions – namely, whether the symptoms which led to the plaintiff’s having surgery in February 2007 and those she experienced thereafter were causally linked to the hit with the soccer ball. The resolution of this issue turns on the Court’s finding as to the history of her symptoms.
 I do not think that the plaintiff deliberately gave false evidence about the history of her symptoms. But I do not think her testimony was accurate or reliable. I do not accept that her symptoms did not go away but got worse until she returned to the general practitioner. Nor do I accept that she experienced arm pain before October 2006. I prefer the chronology as revealed by the general practitioners’ and physiotherapist’s records.
 I am satisfied that the arm symptoms did not emerge until some months after the soccer ball incident. I am satisfied that that incident resulted, at most, in a minor aggravation of pre-existing degenerative change. The symptomatology that led to the plaintiff’s having surgery in February 2007 was not causally linked to her being hit with the soccer ball.
Conclusion on Quantum
 I find that the symptoms which led to the plaintiff’s having surgery in February 2007 and those she experienced thereafter were not causally linked to the hit with the soccer ball.
 As the damages recoverable by the plaintiff would not exceed the amount of the WorkCover “refund”, even if the plaintiff succeeded on liability, the claim should be dismissed.
Brisbane Barrister – David Cormack