Professional Liability Guide

CHAPTER 1 – DUTIES

A plaintiff’s evidence of what they would have done if no breach of duty had occurred is inadmissible except to the extent of the evidence being contrary to the plaintiff’s interests. 90

Even if the parties fail to analyse causation under this statutory test at trial, the court is still obliged to regard it. 91

In Wallace v Kam, the High Court explained the application of the statutory test as follows:

‘A determination in accordance with s 5D(1)(a) that negligence was a necessary condition of the occurrence of harm is entirely factual, turning on proof by the plaintiff of relevant facts on the balance of probabilities in accordance with s 5E. A determination in accordance with s 5D(1)(b) that it is appropriate for the scope of the negligent person’s liability to extend to the harm so caused is entirely normative, turning in accordance with s 5D(4) on consideration by a court of (amongst other relevant things) whether or not, and if so why, responsibility for the harm should be imposed on the negligent party.’ 92 ‘The determination of factual causation’ … ‘involves nothing more or less than the application of a “but for” test of causation. That is to say, a determination … that negligence was a necessary condition of the occurrence of harm is nothing more or less than a determination on the balance of probabilities that the harm that in fact occurred would not have occurred absent the negligence.’ 93 However, the legislation in each jurisdiction provides that in exceptional cases where the but for test cannot be satisfied, the Court may still find that factual causation has been established. 94 This may occur where there are multiple causes of harm, and the contribution of each cause does not satisfy the but for test individually. Further, it may apply to cases where negligent conduct has materially increased the risk of harm, but the current state of scientific or medical knowledge makes it impossible to prove the cause of the plaintiff’s harm, 95 such as cases requiring an analysis of the causation of mesothelioma. In such circumstances, a defendant’s negligence need not be the sole necessary condition for the occurrence of the harm. It is sufficient if a defendant’s negligent act contributes, along with other negligent acts, to the harm suffered. 96 Looking at each element in isolation, the High Court said about the first limb of the test:

90 CLA (Qld) s 11(3)(b); CLA (NSW) s 5D(3)(b); CLA (Tas) s 13(3)(b); CLA (WA) s 5C(3)(b). Victoria, the Australian Capital Territory and South Australia have not enacted a comparable provision. 91 Jamieson v Westpac Banking Corporation (2014) 283 FLR 286; affirmed in Westpac Banking Corporation v Jamieson [2016] 1 Qd R 495; Settlement Group Pty Ltd v Purcell Partners (a firm) [2013] VSCA 370 [98]. 92 (2013) 250 CLR 375, 383. 93 Ibid. 94 CLA (Qld) s 11(2); CLA (NSW) s 5D(2); Wrongs Act (Vic) s 51(2); CLA (ACT) s 45(2); CLA (Tas) s 13(2); CLA (SA) s 34(2); CLA (WA) s 5C(2). 95 Strong v Woolworths Ltd (2012) 246 CLR 182. 96 Strong v Woolworths Ltd (2012) 246 CLR 182; Settlement Group Pty Ltd v Purcell Partners (a firm) [2013] VSCA 370 [99].

17

© Carter Newell 2023