Villa, Dominic --- "Causation under the civil liability acts" [2023] PrecedentAULA 16; (2023) 175 Precedent 14

---

CAUSATION UNDER THE CIVIL LIABILITY ACTS

By Dominic Villa SC

As part of the suite of reforms to the law of negligence introduced by state and territory governments in the early 2000s, most^[1] jurisdictions enacted provisions governing the determination of whether or not a defendant’s failure to exercise reasonable care and skill caused (in a legal sense) damage suffered by a plaintiff.

This article mainly focuses on the provisions in the Civil Liability Act 2002 (NSW), s5D. The NSW provisions are illustrative, although there are some important differences between the various jurisdictions. In NSW, s5D provides as follows:

‘(1) A determination that negligence caused particular harm comprises the following elements:

(a) that the negligence was a necessary condition of the occurrence of the harm (“factual causation”), and

(b) that it is appropriate for the scope of the negligent person's liability to extend to the harm so caused (“scope of liability”).

(2) In determining in an exceptional case, in accordance with established principles, whether negligence that cannot be established as a necessary condition of the occurrence of harm should be accepted as establishing factual causation, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.

(3) If it is relevant to the determination of factual causation to determine what the person who suffered harm would have done if the negligent person had not been negligent:

(a) the matter is to be determined subjectively in the light of all relevant circumstances, subject to paragraph (b), and

(b) any statement made by the person after suffering the harm about what he or she would have done is inadmissible except to the extent (if any) that the statement is against his or her interest.

(4) For the purpose of determining the scope of liability, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.’

Despite some early suggestions that these provisions reflected the common law,^[2] it is now clear that s5D and its cognate provisions in other jurisdictions effected a substantive change to the law of causation.^[3] In many cases the ultimate outcome will be the same whether causation is determined by reference to the common law or by reference to s5D. The High Court, however, has emphasised that it is the applicable statutory provision that must prevail.^[4]

CAUSATION GENERALLY

In each jurisdiction that has enacted a statutory test of causation, the main provision has the effect that a determination that negligence^[5] caused particular harm requires a plaintiff to establish two elements: ‘factual causation’ and ‘scope of liability’. In Wallace v Kam,^[6] the High Court described this as:

‘a question of historical fact as to how particular harm occurred; and a normative question as to whether legal responsibility for that particular harm occurring in that way should be attributed to a particular person.’

FACTUAL CAUSATION

The High Court has made it clear that the determination of factual causation under s5D(1)(a) is a statutory statement of the ‘but for’ test of causation.^[7]

It is necessary, in order to establish factual causation under s5D(1)(a), for a plaintiff to prove on the balance of probabilities that they would not have suffered the particular harm but for the defendant's negligence. Where there are competing inferences of equal degrees of probability, factual causation is not established, as ‘any choice among them is no more than speculation’. ^[8]

In Strong v Woolworths Ltd,^[9] the High Court noted that the ‘but for’ test produced anomalous results in particular cases, exemplified by cases of causal over-determination where there is ‘more than one sufficient condition of the plaintiff's harm’. However, the Court went on to say in relation to s5D(1)(a):

‘A necessary condition is a condition that must be present for the occurrence of the harm. However, there may be more than one set of conditions necessary for the occurrence of particular harm and it follows that a defendant's negligent act or omission which is necessary to complete a set of conditions that are jointly sufficient to account for the occurrence of the harm will meet the test of factual causation within s 5D(1)(a).’^[10]

As discussed below, various jurisdictions have enacted additional provisions to assist plaintiffs in proving factual causation in certain particular circumstances.

SCOPE OF LIABILITY

Once factual causation has been established, s5D(1)(b) then requires a determination that it is appropriate for the scope of the defendant's liability to extend to that harm. This is referred to as the ‘scope of liability’ requirement.

In a case falling within an established class or category, the normative question posed by s5D(1)(b) is properly answered by a court through the application of precedent (including precedents applying the common law).^[11]

In the absence of precedent, s5D(4) requires a court to consider the ‘policy considerations that are bound up in the attribution of legal responsibility for harm’ that are absent from the application of factual causation,^[12] and to explain in terms of legal policy whether or not responsibility for the harm should be imposed on the negligent party, and if so why. What is required in such a case is the identification and articulation of an evaluative judgment by reference to the purposes and policy underlying the particular rule or norm of conduct in question.

The common law limitations upon the scope of a defendant’s liability remain relevant to the determination of scope of liability under s5D.^[13] For example, the scope of liability in negligence normally does not extend beyond liability for the occurrence of harm that it was the duty of the negligent party to exercise reasonable care and skill to avoid. A useful example, expressly endorsed by the High Court, is that of a mountaineer who is negligently advised by a doctor that his knee is fit to make a difficult climb and who then makes the climb, which he would not have made if properly advised about his knee, only to be injured in an avalanche. His injury is a ‘foreseeable consequence of mountaineering but has nothing to do with his knee’.^[14]

In Monaghan Surveyors Pty Ltd v Stratford Glen-Avon Pty Ltd,^[15] Basten JA suggested that the normative inquiry under s5D(1)(b) will also include the matters formerly taken into account by the common law in dealing with causal over-determination, intervening and successive causes, and remoteness.

EXCEPTIONAL CASES

As noted above, various jurisdictions have enacted additional provisions to assist plaintiffs in proving factual causation in certain particular circumstances. Two different approaches have been taken.

The first is the relatively narrow approach adopted in the ACT and South Australia. These provisions apply where ‘a person ... has been negligently exposed to a similar risk of harm by a number of different persons ... and it is not possible to assign responsibility for causing the harm to any one or more of them’.^[16] One only gets to these exceptional provisions where it has been impossible to establish factual causation to begin with. In such a case the court may continue to apply the existing common law principles under which responsibility may be assigned to the defendants for causing the harm, and the court should consider the position of each defendant individually and state the reasons for bringing the defendant within the scope of liability. The South Australian version of this provision includes an express reference to the House of Lords decision in Fairchild v Glenhaven Funeral Services Ltd (Fairchild).^[17]

The second approach has been adopted in NSW (s5D(2)) and in similar terms in Queensland, Tasmania, Victoria and Western Australia. These provisions are said to apply in determining in an ‘exceptional case’ (in NSW, Queensland and Tasmania) or an ‘appropriate case’^[18] (in Victoria and Western Australia), ‘in accordance with established principles’, whether negligence that cannot be established as a necessary condition of the occurrence of harm should be taken to establish factual causation. In such cases ‘the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party’.

The origin of the exceptional provisions lies in the Ipp Review Panel’s^[19] consideration of two categories of cases in which they deemed it appropriate that a plaintiff should nonetheless succeed, notwithstanding the fact that as a result of ‘evidentiary gaps’ they could not establish that the defendant's negligence was a necessary condition of the harm.

The first category of case is where harm is brought about by the cumulative operation of two or more factors, but which is indivisible in the sense that it is not possible to determine the relative contribution of the various factors to the total harm suffered. This category is illustrated by the decision of the House of Lords in Bonnington Castings v Wardlaw.^[20]

The second category of case is where the same negligence of successive defendants was capable of causing the harm that resulted, but it is impossible to determine which of the defendants in fact caused the harm. This category is illustrated by the decision of the House of Lords in Fairchild.^[21]

While the scope of s5D(2) is uncertain, what is clear is that it does not apply simply because the evidence is insufficient to establish that the harm would not have occurred absent negligence by the defendant.^[22]

Dominic Villa SC practises from New Chambers in Sydney, and specialises in tort law. He is the author of the Annotated Civil Liability Act 2002 (NSW).

---

^[1] The Northern Territory has not enacted a general provision relating to causation. The provisions in the other jurisdictions are Civil Law (Wrongs) Act 2002 (ACT), s45;Civil Liability Act 2003 (Qld), s11; Civil Liability Act 1936 (SA), s34; Civil Liability Act 2002 (Tas), s13; Wrongs Act 1958 (Vic), s51; Civil Liability Act 2002 (WA), s5C.

^[2] See, for example, Ruddock v Taylor [2003] NSWCA 262; (2003) 58 NSWLR 269, [89] (Ipp JA); Tambree v Travel Compensation Fund [2004] NSWCA 24, [146] (Sheller JA); Harvey v PD [2004] NSWCA 97; (2004) 59 NSWLR 639, [106] (Santow JA) and [185]–[191] (Ipp JA) (Spigelman CJ expressly reserved his position at [11]); Nguyen v Cosmopolitan Homes (NSW) Pty Ltd [2008] NSWCA 246, [67]–[70] (McDougall J); Elayoubi v Zipser [2008] NSWCA 335, [55] (Basten JA); and Mobbs v Kain [2009] NSWCA 301, [107] (McColl JA).

^[3] Paul v Cooke [2013] NSWCA 311; (2013) 85 NSWLR 167 (Cooke) [41] (Leeming JA), referring with apparent approval to B McDonald, ‘The impact of the Civil Liability legislation on fundamental polices and principles of the common law of negligence, Torts Law Journal, Vol. 14, No. 3, 2006, 268.

^[4] Adeels Palace Pty Ltd v Moubarak [2009] HCA 48; (2009) 239 CLR 420 (Adeels) [44].

^[5] In this article a reference to ‘negligence’ is generally a reference to the statutory term, defined to mean a failure to exercise reasonable care and skill, whether by virtue of the tort of negligence, pursuant to contract, breach of statutory duty, or otherwise.

^[6] [2013] HCA 19; (2013) 250 CLR 375 (Wallace) [11].

^[7] Adeels, above note 4, [45]; Strong v Woolworths Ltd [2012] HCA 5; (2012) 246 CLR 182 (Strong), [18]; Wallace, above note 6, [16].

^[8] Perisher Blue Pty Ltd v Nair-Smith [2015] NSWCA 90; (2015) 90 NSWLR 1, [163].

^[9] Strong, above note 7.

^[10] Ibid, [20].

^[11] Wallace, above note 6, [22]; Zanner v Zanner [2010] NSWCA 343; (2010) 79 NSWLR 702, [8].

^[12] Strong, above note 7.

^[13] Wallace, above note 6, [24].

^[14] South Australia Asset Management Corp v York Montague Ltd [1996] UKHL 10; [1997] AC 191, 213. See Cooke, above note 3.

^[15] [2012] NSWCA 94, [70].

^[16] Civil Liability Act 1936 (SA), s34(2); Civil Law (Wrongs Act) 2002 (ACT), s45(2).

^[17] [2002] 1 AC 32 (Fairchild).

^[18] The Western Australia Court of Appeal has suggested the difference in language ‘may be significant’: Department of Housing and Works v Smith (No 2) (2010) 41 WAR 217, [90].

^[19] Panel of Eminent Persons, Review of the Law of Negligence: Final Report (Ipp Review) (2002).

^[20] [1956] UKHL 1; [1956] AC 613.

^[21] In Adeels, above note 4, the High Court left open the question of whether or not s5D(2) would be engaged in a case such as Fairchild, although it was clearly intended by the Ipp Review Panel that Fairchild was the very type of case to which s5D was directed. See above note 19, [7.32].

^[22] Carangelo v New South Wales [2016] NSWCA 126, [81]; Powney v Kerang and District Health [2014] VSCA 221; (2014) 43 VR 506, [96]–[97].