Breach of duty and causation of damage

— persuasive and evidentiary onuses in operation

The common law stipulates that a plaintiff, as moving party in a cause of action for damages for breach of a tortious or contractual duty of care, bears the persuasive onus of proving the breach and causation of damage.

On such issues, an evidentiary onus (or tactical burden) may shift to the defendant, but the plaintiff remains shouldered with the primary onus.

What is entailed in the endeavour of  discharging each onus? The point of this article is to address that question, in particular the latter onus which can only be treated through the focus of the former onus.

In addressing such question, I will only touch upon the relevant provisions of the Civil Liability Act 2003 (Qld) (“CLA”) and the cognate provisions in Pt 8 of Ch 5 of  the Workers’ Compensation and Rehabilitation Act 2003 (Qld). The issues I address transcend the content of such legislation.

Such issues apply to causes of action irrespective of whether the damage sustained is property, personal injury or economic in character. That stated, many of the cases are decided in the context of cause for personal injury damages.

Proof on the balance of probabilities:

Each of breach of duty and causation of damage is an issue of mixed fact and law requiring proof on the balance of probabilities. 

The parties plead and proceed to prove germane material facts by adducing admissible evidence.  In turn, by application of the law to the facts proved, the alleged breach and causal nexus respectively are adjudicated as ultimate issues.

Often the significant basal material facts, and inevitably the ultimate adjudication, fall to be proved (or not) by inference.  The touchstone of such proof is whether, on the basis of the primary facts otherwise found, it is reasonable to draw the inference sought:  Luxton v Vines.[1]

In Briginshaw v Briginshaw,[2] in referring to what constituted “proof” of a fact, Dixon J wrote:

            … the tribunal must feel an actual persuasion of its occurrence or existence before it can be found.  It cannot be found as a result of mere mechanical comparison of probabilities independently of any belief in its reality.

In Jones v Dunkel,[3] Dixon CJ wrote of adjudication of the ultimate issue:

            In an action of negligence for death or personal injuries the plaintiff must fail unless he offers evidence supporting some positive inference implying negligence and there must be an inference which arises as an affirmative conclusion from the circumstances proved in evidence and one which they establish to the reasonable satisfaction of a judicial mind …  The law … does not authorise a court to choose between guesses, where the possibilities are not unlimited, on the ground that one guess seems more likely than another or the others. The facts must form a reasonable basis for a definite conclusion affirmatively drawn from the truth of which the tribunal of fact may reasonably be satisfied. 

Recently, in Henderson v Queensland,[4] Gageler J, while dissenting in the ultimate result, usefully assembled the established jurisprudence. It is worth quoting at length:

[89] Generally speaking, and subject always to statutory modification, a party who bears the legal burden of proving the happening of an event or the existence of a state of affairs on the balance of probabilities can discharge that burden by adducing evidence of some fact the existence of which, in the absence of further evidence, is sufficient to justify the drawing of an inference that it is more likely than not that the event occurred or that the state of affairs exists. The threshold requirement for the party bearing the burden of proof to adduce evidence at least to establish some fact which provides the basis for such a further inference was explained by Kitto J in Jones v Dunkel (1959) 101 CLR 298 at 305; [1959] HCA 8. See also Carr v Baker(1936) 36 SR (NSW) 301 at 306; TNT Management Pty Ltd v Brooks(1979) 53 ALJR 267 at 269 ; 23 ALR 345 at 350. See generally Hodgson, “The Scales of Justice: Probability and Proof in Legal Fact-finding“, (1995) 69 Australian Law Journal 731 at 732—733:

One does not pass from the realm of conjecture into the realm of inference until some fact is found which positively suggests, that is to say provides a reason, special to the particular case under consideration, for thinking it likely that in that actual case a specific event happened or a specific state of affairs existed.

[90] That description of the ordinary operation of the civil standard of proof applies equally to a case in which the legal burden of a party is to prove the non-happening of an event or the non-existence of a particular state of affairs as to a case in which a party’s legal burden is to prove the happening of an event or the existence of a particular state of affairs. As Davidson J earlier explained in the Supreme Court of New South Wales in Ex parte Ferguson; Re Alexander (1944) 45 SR (NSW) 64 at 70:

In all legal proceedings the basic principle at common law is that in civil cases a plaintiff must prove the essential elements of his case even if that course involves establishing the assertion of a negative … He must establish what is really the affirmative in substance, not what is merely affirmative in form … But if the party bearing the onus furnishes some evidence which gives rise to a presumption or inference of fact in his favor or that presumption already exists, the onus shifts to the other party.

His Honour’s reference to evidence adduced by the party bearing the legal burden of proof giving rise to a “presumption or inference of fact“ was to nothing more than an inference of fact drawn, in accordance with ordinary processes of inferential reasoning, in the absence of further evidence:  Cross on Evidence, 9th Aust ed (2013) at 297 [7240], 299 [7255]. His Honour’s reference to an “onus“ then shifting to the other party was to nothing more than the practical need (sometimes referred to as a “tactical burden“) for an opposing party to adduce further evidence if that party wants to prevent such an inference of fact actually being drawn in the circumstances of the case:  Cross on Evidence, 9th Aust ed (2013) at 293 [7215].

[91] The process of inferential reasoning involved in drawing inferences from facts proved by evidence adduced in a civil proceeding cannot be reduced to a formula. The process when undertaken judicially is nevertheless informed by principles of long standing which reflect systemic values and experience. One such principle, forming “a fundamental precept of the adversarial system of justice“:  Russo v Aiello(2003) 215 CLR 643 at 647 [11]; [2003] HCA 53, is that “all evidence is to be weighed according to the proof which it was in the power of one side to have produced, and in the power of the other to have contradicted“:  Blatch v Archer(1774) 1 Cowp 63 at 65 [ 98 ER 969 at 970]. See also Houston v Wittner’s Pty Ltd(1928) 41 CLR 107 at 122 ; [1928] HCA 34; Hampton Court Ltd v Crooks(1957) 97 CLR 367 at 371—372 ; [1957] HCA 28; G v H(1994) 181 CLR 387 at 391—392 ; [1994] HCA 48; Vetter v Lake Macquarie City Council(2001) 202 CLR 439 at 454 [36]; [2001] HCA 12.   …  [Emphasis added]

In Strong v Woolworths Ltd,[5] a New South Wales CLA case, Heydon J (then and now the editor of the Australian Edition of “Cross on Evidence”) wrote:

[53] …  “evidential burden” refers to circumstances in which a plaintiff calls evidence sufficiently weighty to entitle, but not compel, a reasonable trier of fact to find in the plaintiff’s favour. There is then said to be an “evidential burden” in the sense of a “provisional” or “tactical” burden on the defendant: if the defendant fails to call any or any weighty evidence, it will run a risk of losing on the issue — that is, a risk that at the end of the trial the trier of fact will draw inferences sufficiently strong to enable the plaintiff to satisfy the legal (ie persuasive) standard of proof. The “provisional” or “tactical” burden raises the question whether a defendant should as a matter of tactics “call evidence or take the consequences, which may not necessarily be adverse”.  [Emphasis added]

In the course of reasoning in adjudication of causative breach of duty, the court must keep at the forefront of its mind that the plaintiff bears the persuasive onus of proof, but subject to the shifting to the defendant of any evidentiary onus (or “tactical burden” or “evidential burden”, as Gageler J and Heydon J, respectively, described it).   

To describe this latter onus as the ordinary Jones v Dunkel onus, however, does not furnish adequate flesh to the bones of the principle entailed.  To the contrary, the  Jones v Dunkel onus is but an example of evidentiary onus.

If a defendant leads plausible evidence in discharge of any evidentiary onus with which it is taxed, the evidentiary onus shifts back to the plaintiff, merging with the persuasive onus.  Such shifting between parties persists during trial, sometimes with each answer given in testimony.

I turn now to address operation of persuasive and evidentiary onus in proof of breach of duty and causation respectively.

Breach of duty:

(a) Persuasive onus:

Sections 9 and 10 of the CLA, like their interstate analogues, in respect of a proven duty of care at common law (contractual or tortious), delineate the content of the enquiry as to breach of such duty.  These provisions mirror the common law, with the exception that the risk which materialises must be proved as having been prospectively “not insignificant”.

In Town of Mosman Park v Tait,[6] the Court of Appeal of Western Australia identified succinctly the core content of the inquiry upon breach adjudication:

[50] Proper inquiry at the breach stage of the negligence analysis involves identifying with some precision what a reasonable person would do by way of response to a reasonably foreseeable risk (Graham Barclay at [192]). In this case the alleged breach was the [defendant] appellant’s failure to have a proper system of inspection of the oval. That being the case, it was incumbent upon the [plaintiff] respondent to demonstrate that there was some system of inspection which was an alternative to that which the appellant was using at the time of the accident which was free of or reduced the risk complained of and which was available in a practical sense: Trustees of the Roman Catholic Church for the Diocese of Canberra and Goulburn v Hadba [2005] HCA 31 at [13]. That formulation requires an eye to issues of causation; that is, a system that would or could have prevented the respondent’s injury: Trustees of the Roman Catholic Church at [27].

[51] The respondent was required to identify with precision what a reasonable person would do, either by reference to industry standards or practice and the financial or other impacts of the proposed system: Trustees of the Roman Catholic Church at [14].

In many cases, proof of breach will behove the plaintiff, as moving party, to adduce probative expert evidence going to the risk of damage, together with the reasonable and appropriate precautions which ought have been taken to diminish such risk.  Not to so do courts the risk of litigious failure.[7]

But that is not always so.  In a case  where the risk of damage or injury is high, and  the efficacy of practical alternatives intuitive, breach may still be inferred.  Examples include the risk of being burned while carrying a container of hot tar – Hamilton v Nuroof (WA) Pty Ltd[8] – and the risk of injury from a large hand-held mechanical suction pump – Kuhl v Zurich Financial Services Aust Ltd[9]. Another example is a  motor vehicle injury case, entailing enquiry as to due  care in accordance with statutory road rules and otherwise sensible driving practices.

Invariably expert evidence will be required in causes of action for professional negligence.  The view persists that is not so in causes against legal professionals,[10] but that is not always so.[11]  

(b) Evidentiary onus:

On the facts of any particular case, an evidentiary onus (or tactical burden)  apropos proof of breach may shift to the defendant.  Archetypally, this occurs where, the evidence discloses that, subsequent to the occurrence of damage to the plaintiff, the defendant adopts a remedial measure which, if it had been in place prior to the occurrence of the litigated damage, would have obviated or minimised the risk of that damage ensuing.   

Ordinarily, a defendant would address in evidence the reason for, or circumstances leading to such later adoption, including whether or not it constituted a response to the litigated occurrence.  Sometimes such occurrence, historically, was low in likelihood.  The question would remain whether, prior to that occurrence, the probability of damage and its likely moment, along with practical matters of expense, and difficulty and inconvenience, militated for or against earlier adoption.

This common law position is entrenched by s 10 of the CLA:

10 Other principles

In a proceeding relating to liability for breach of duty happening on or after 2 December 2002— …

(c) the subsequent taking of action that would (had the action been taken earlier) have avoided a risk of harm does not of itself give rise to or affect liability in relation to the risk and does not of itself constitute an admission of liability in connection with the risk.

As Tobias JA (Giles and Handley JJA agreeing) wrote, in a New South Wales CLA context, in Brighton Le Sands Amateur Fishing Association Ltd v Koromvokis:[12]

[33] The fact that the appellant [defendant], in circumstances unrelated to the [plaintiff]  respondent’s accident, subsequently adopted a course which the respondent now says it should have adopted at an earlier point of time, does not necessarily lead to the conclusion that in the circumstances it was unreasonable for the appellant not to have adopted that course in order to eliminate the relevant risk. The response to that risk must be one which is reasonable in all the circumstances at a point of time immediately prior to the accident that gives rise to the inquiry.

If, however, a defendant fails to give evidentiary treatment to the subsequent measure adopted by it, considerations such as expense, difficulty and inconvenience of that measure may be accorded much lesser significance in the adjudication.   Despite this, the plaintiff must still address the prospective probability and moment of harm.

New South Wales Land and Housing Corporation v Watkins[13] concerned proof of breach in a case in which the plaintiff was a leasehold tenant of a house the property of the defendant, who when showering fainted and suffered injury due to exposure to high temperature from a hot water system which remained unrepaired. Heydon JA (Hodgson JA agreeing) wrote:

[78] One difficulty with the defendant’s argument is that after the accident the defendant removed the hot water system and substituted a mains pressure hot water system. This change is not of itself evidence of negligence: Hart v Lancashire & Yorkshire Rail Co (1869) 21 LT 261 at 263;  Davis v Langdon (1911) 11 SR (NSW) 149. The change is “relevant not to what should have been done but to what could have been done”: Glass, McHugh and Douglas, The Liability of Employers (2nd ed), p 35. This Court was not taken to any evidence of the cost of that change in the hot water system. The legal burden of proving a breach of duty lay on the plaintiff. That in turn meant that the plaintiff bore a legal burden of proving that in all the circumstances it was unreasonable for the defendant not to take the precaution of changing the hot water system before the accident in the way it did after the accident. Even if the plaintiff as a result bore a burden of proof in relation to negating expense, difficulty and inconvenience of making the change, the observations of Gibbs J (with whom Stephen J and Mason J agreed) in Nelson v John Lysaght (Australia) Ltd [1975] HCA 9; (1975) 132 CLR 201 at 214-215 are relevant:

“the appellant [plaintiff] has shown that it was practicable to provide a new method of doing the work that would eliminate or minimize the risk, because such a new method has in fact been put into operation. In determining whether a reasonable employer would have provided such a new system it would be necessary to consider not only the degree of risk of accident and injury likely to result if no such provision were made, but also the disadvantages, if any, of taking the suggested precaution … . The onus of proving that it was unreasonable not to take the precaution, of course, lay on the appellant. However, when the respondent [defendant], which must have had full knowledge of the nature, cost and practical consequences of the new installation, gave no evidence, and by its counsel asked no questions, to suggest that it was inordinately expensive or in any other way disadvantageous, the jury was entitled to infer at the very least that the advantages of the method which the respondent has since adopted were not outweighed by any disadvantages.”

[79] So here, the defendant would have known the nature, cost and practical consequences – the “expense, difficulty and inconvenience” – of the change. Its failure to call evidence on these questions justifies an inference that the advantages of the new system were not outweighed by any disadvantages.

[80] But it is questionable whether the plaintiff did bear a burden of negating expense, difficulty and inconvenience. Those issues on which one or other party bears a legal burden of proof are factual issues on which the validity of the cause of action or ground of defence depends. According to J B Thayer’s Preliminary Treatise on Evidence of the Common Law (Boston, Little Brown & Co, 1898), p 355, what is known in modern Australian law as the legal burden of proof is the:

“peculiar duty of him who has the risk of any given proposition on which the parties are at issue, – who will lose the case if he does not make this proposition out, when all has been said and done.”

A plaintiff bears the burden of proving facts constituting a cause of action (for example, in a contract case, agreement on particular terms, intention to affect legal relations, and either a seal or consideration). A defendant bears the burden of proving the constituent facts of a defence which would defeat the cause of action alleged (for example, in a contract case, illegality or accord and satisfaction). But that there is little expense in alleviating a risk is not a fact on which either side bears a legal burden of proof in a negligence case: it is not a matter which, if not established, will cause a plaintiff to lose. It is a matter which, if established, assists a plaintiff in succeeding in discharging the burden that that plaintiff bears of proving breach. It is a matter which, if negated by the defendant, assists the defendant in preventing the plaintiff from discharging the plaintiff’s burden of proving breach. But it is not a matter success on which is crucial to either party, because it is simply one factor among several to be considered in assessing the response of a reasonable man to the risk.   [Emphasis added]

In a like vein, omission by a defendant to adduce evidence in its case, even from the witnesses it does call, so as  to obviate or diminish the reasonableness of what appears to have been a plain remedial measure which was open to the defendant, albeit not necessarily later adopted, can prove fatal to a defendant’s prospects.

In Swain v Waverley Municipal Council,[14] the plaintiff was a swimmer at Bondi Beach who suffered severe injury when he dived into the wall of a sandbar while surfing between the flags at a superintended beach controlled by the defendant Council.  The plaintiff secured a favourable jury verdict in circumstances where he alleged, inter alia, that the Council ought have placed the swimming area flags further down the beach away from the sandbar.  The High Court concluded that the verdict ought not be disturbed having regard to that evidence which was open to the jury to accept.

Specifically as to such allegation, upon which the defendant Council gave no evidence, Gleeson CJ observed:

[17]   More than 200 years ago, Lord Mansfield [in Blatch v Archer] said that “all evidence is to be weighed according to the proof which it was in the power of one side to have produced, and in the power of the other to have contradicted.”  This basic principle of adversarial litigation is not a matter of esoteric legal knowledge; it accords with common sense and ordinary human experience. When the jurors in this case were asked to consider whether the flags should have been placed elsewhere, they may have thought that it was up to the respondent [Council], rather than the appellant [plaintiff], to tell them what difficulty there would have been about moving the flags to avoid the sand bank, or to explain why nothing would have been gained by putting the flags in a different location. That is something they might reasonably have taken into account in making a judgment about the reasonableness of the conduct of the respondent.

Gummow J added:

[153]  While the plaintiff bears the ultimate burden of proving that his or her injuries could have been avoided by some reasonably practicable alternative course of conduct available to the defendant, in some cases, the evidentiary burden which has come to rest upon the defendant may prove decisive of the outcome.

…

[155]  Here, also, the Council, as indicated above, led no evidence and asked no questions upon critical matters. The Council’s witness, Mr Nightingale, was the person well placed to give evidence upon these matters. It was open to the jury to infer, for example, that the Council could have moved the flags. In the circumstances of the trial, the Council had carried at least an evidentiary onus to lead evidence that no reasonably practicable alternative course of conduct was open to it.

In Kuhl v Zurich Financial Services Aust Ltd, as above, at [63], three members of the High Court wrote:

            Where counsel for a party has refrained from asking a witness whom that party has called particular questions on an issue, a court will be more likely to draws inferences favourable to that party from other evidence in relation to that issue.

See also Sullivan Nicolaides Pty Ltd Papa.[15]

A further relevant consideration as to breach is the existence of any prior damage suffered or complaints made pertaining to materialisation of the relevant risk.  The existence, or not, of prior damage or complaint can be powerful probative evidence in the hands of a plaintiff defendant[16] albeit is not determinative[17] of breach. 

Evidentiary onus apropos such evidence  was addressed in Bathurst Regional Council v Thompson.[18]  In an occupier’s liability context, it was concluded that that absence of evidence adduced as to such antecedent matters rendered the issue, at highest, a neutral matter in breach adjudication:

[57] An important element of the [defendant] appellant’s submission is the proposition, which was rejected by the trial judge, that the lack of evidence of complaint or previous injury, coupled with the use of the park and rotunda by many people, required an inference to be drawn that there were no complaints and no previous injuries.

[58] That submission should not be accepted. The evidentiary position was as explained by his Honour. There was no evidence of complaints or previous injuries. This should be distinguished from evidence that there had been no complaints or previous injuries. They are two quite different things. The absence of evidence on the subject means that there could have been complaints or previous injuries, but there was simply no evidence either way.

[59] His Honour correctly concluded that a lack of evidence on the subject did not assist either party and that not only was he not required to draw the inference sought by the appellant, but it was not open to him to do so.

[60] If any inference were to be drawn, it would have been an inference adverse to the appellant. It was the party in the best position to provide evidence of whether there had been complaints or previous injuries, but it declined to do so. It was open to his Honour to draw an inference, had he so wished, that such evidence would not have assisted the appellant.              [Emphasis added]

Finally,  a shifting of an evidentiary onus may occur where a defendant relies upon third party delegation of the duty.  In effect, in such a case, the plea of the defendant  is that it has discharged the duty it owes to exercise reasonable care by engaging an expert independent contractor to undertake the relevant task, and has undertaken apt steps to check a proper undertaking of same.[19]

In Laresu v Clarke,[20] the point was made in an occupier’s liability context, where a commercial property owner engaged a managing agent:

[69] … Generally, the plaintiff (in this case, Mr Clark) has the onus of proving his or her case on the balance of probabilities. However if, as here, the plaintiff proves in an action against the occupier that reasonable care has not been taken to render premises safe for use by the plaintiff, it is in my view unnecessary for the plaintiff to negative delegation by the occupier of its responsibility to take reasonable care for the safety of the plaintiff unless the occupier has introduced evidence suggesting that this may have occurred. Thus, as I see it, there is an evidentiary onus on the occupier to lead some evidence of any suggested delegation.

[70] The [defendant] Owner discharged this onus in the present case as it tendered the Management Agency Agreement and because there was also evidence before the court that the  [further defendant] Managing Agent had had considerable experience in managing properties, had done so for the Owner on an extensive basis and had the practice of recording and acting upon complaints made concerning the premises.   [Emphasis added]

Delegation cannot avail a defendant when the tortious duty owed falls into a non-delegable category eg escape of fire[21], over spraying, [22] land support[23].  Nor does it circumvent, ordinarily, contractual duties of care, given the duty content thereof is that reasonable care will be exercised.[24]

Causation:

(a) Persuasive onus:

What is required for proof of causation in a duty of care case has been the subject of statutory modification, in Queensland by ss 11 and 12 of the CLA. Section 12 underscores the common law position that the persuasive onus of proof of causation lies at all times with the plaintiff. That prescription, however, does not preclude the shifting of an evidentiary onus to the defendant (see below).

In discharging the persuasive onus, in a case of breach of duty of care by the defendant in failing to take a particular step (that being the usual position), the overarching question is whether the taking of such step: [25]

            … more probably than not … would have prevented or minimised the injury which was in fact received.  [Emphasis added]

Expressed another way, a defendant who negligently exposes a plaintiff to risk of injury or damage, will not be liable:[26]

            … unless the plaintiff can persuade the trier of fact that it was probable the risk came home. [Emphasis added].

A court, however, ought not be left to speculate.  In Miller v Council of the Shire of Livingstone,[27] McPherson JA expressed the position succinctly by reference to a case in which breach of duty was proved but the causation of injury was not for want of  eye-witness evidence as to its manner of occurrence:

[4] It is not, however, enough to think up other competing hypotheses that are more or less favourable to the success of the plaintiff’s claim. No one can say that one of them is more probable than another because no one can say what in fact happened. The case is covered by what Lord Watson said in Wakelin v London & Southwestern Rye Co (1886) 12 App Cas 41, 47:

“Mere allegation or proof that the company were guilty of negligence is altogether irrelevant; they might be guilty of many negligent acts or omissions, which might possibly have occasioned injury to somebody, but had no connection whatever with the injury for which redress is sought; and therefore the plaintiff must allege and prove, not merely that they were negligent, but that their negligence caused or materially contributed to the injury”.

See also Fraser v Victorian Railway Commissioners (1990) 8 CLR 54, 59, 66. These decisions are old, but the principle has not changed. In the absence of evidence, speculation is not enough. It was necessary for the plaintiff to prove how or why he fell. Inference from proved facts will do, but not mere hypothesis. The circumstantial evidence in the present case does not support an inference that the plaintiff’s injuries resulted from the negligence of the defendants or either of them in installing or maintaining a fence that was too low rather than from some other cause that is inconsistent with negligence on their part.     [Emphasis added]

The High Court has sanctioned “probabilistic” reasoning in the adjudication of causation.   In Strong v Woolworths Ltd,[28] a case decided under the New South Wales CLA, the High Court addressed the issue of causation in the  historically vexed sphere of supermarket litter.  Causation was inferred on the facts:

[34] Woolworths’ submission that it was necessary for the appellant to point to some evidence permitting an inference to be drawn concerning when the chip was deposited must be rejected. It was incumbent on the appellant to prove that it was more probable than not that Woolworths’ negligence was a necessary condition of her fall, but this onus could be discharged by consideration of the probabilities in circumstances in which the evidence did not establish when the chip was deposited. The point was illustrated by Hayne JA (as he then was) in Kocis v S E Dickens Pty Ltd.   His Honour posited a case in which reasonable care required the occupier of premises to carry out inspections at hourly intervals. Assume that no inspection is made on the day the plaintiff slips on a spill eight hours after the premises opened for trading. If there is no basis for concluding that the spill is likely to have occurred at some particular time rather than any other time, the probability is that that the spill occurred in the first seven hours of trading and not in the hour preceding the plaintiff’s fall.   As Hayne JA observed, a plaintiff must prove his or her case on the balance of probabilities and it is no answer to the question whether something has been demonstrated as being more probable than not to say that there is another possibility open.  The determination of the question turns on consideration of the probabilities.

…

[38] Reasonable care required inspection and removal of slipping hazards at intervals not greater than 20 minutes in the sidewalk sales area, which was adjacent to the food court. The evidence did not permit a finding of when, in the interval between 8.00 am and 12.30 pm, the chip came to be deposited in that area. In these circumstances, it was an error for the Court of Appeal to hold that it could not be concluded that the chip had been on the ground for long enough for it to be detected and removed by the operation of a reasonable cleaning system.   The probabilities favoured the conclusion that the chip was deposited in the longer period between 8.00 am and 12.10 pm and not the shorter period between 12.10 pm and the time of the fall.

(b) Evidentiary onus:

Where the damage or injury which ensues falls squarely within the scope or envelope of the risk entailed in the breach of duty proved, an evidentiary onus may shift to the defendant.  The persuasive onus, however, remains with the plaintiff.

Thus, in a manner not inconsistent with the prescription of onus now encapsulated in s 12 of the CLA, the authorities recognise that the common law allows of a shifting of an evidentiary onus (or tactical burden) to the defendant to identify the role of the non-negligent candidates causes of the relevant damage or injury.

In Fitzpatrick v Job,[29] Buss JA (Steytler P agreeing), collecting the authorities, wrote:

[225] The judgment of McHugh J in Commissioner of Main Roads v Jones (2005) 79 ALJR 1104 is consistent with the analysis of Mason P in TC. McHugh J said, at 1109 [26]:

This was not a case where the only evidence concerning causation was that the defendant had breached his duty of care and that the injury that occurred was within the scope of the risk of injury arising from the breach of duty (cf Chappel v Hart (1998) 195 CLR 232 at 244 [27]; Naxakis v Western General Hospital (1999) 197 CLR 269 at 279 [32], 312 [128]). In such cases, it is always open to the tribunal of fact to find a causal connection between the breach and the injury even though the exact cause of the injury or conduct of the plaintiff is unknown (cf Hamilton v Nuroof (WA) Pty Ltd (1956) 96 CLR 18 at 24 and 27).

A similar point was also made by Callinan J, who said, at 1119 [80]:

This was not a case in which cause could be inferred from the result, that is the collision. In the dictum of Gaudron J in Bennett ((1992) 176 CLR 408 at 420) … there is reference to a statement by Dixon J in Betts v Whittingslowe ((1945) 71 CLR 637 at 649), a case of breach of statutory duty, to the effect that the breach coupled with the fact of an accident of the kind that might thereby be caused, is enough to justify an inference that in fact the accident occurred owing to the breach. But contained within that statement is the important qualification of an absence of any sufficient reason to the contrary.

[226] As Keane JA noted in Gold Ribbon (Accountants) Pty Ltd (in liq) v Sheers [2006] QCA 335, at [277]—[278], the approach of McHugh J in Chappel in relation to inferring from:

(a)  the creation or increase in the risk of an event as a result of a breach of duty; and

(b)  the actual occurrence of the event in question,

that the breach caused or materially contributed to the event, involves the logical inference of a causal nexus, and not a legal presumption which obviates the necessity to prove a causal nexus. Keane JA then continued, at [278]:

As McHugh J himself said in Commissioner of Main Roads v Jones (2005) 79 ALJR 1104 at 1109 [26]), the approach to causation which he explained in Chappel v Hart is appropriate to cases ‘where the only evidence concerning causation was that the defendant had breached his duty of care and that the injury that occurred was within the scope of the risk of injury arising from the breach of duty’. The inference of causation is a deduction which may logically be made in a case where the risk created or increased by the defendant’s breach of duty may operate, either alone or with other risks attending particular action or enterprise, to produce the loss. But it is not a logical deduction where the evidence either shows that the removal of the risk created by the defendant’s breach of duty would not have prevented the occurrence of the loss by reason of the operation of the other attendant risks, or gives reason to regard the possibility of such a result as equally probable.

In summary, the tribunal of fact is entitled, but not obliged, to find that causation has been established if:

(a)  the defendant’s breach of duty has created or increased the risk of an event which may result in the plaintiff (or a class of persons including the plaintiff) suffering reasonably foreseeable loss or damage;

(b)  the event in question occurs; and

(c)  the defendant has not satisfied the evidentiary onus of pointing to other evidence which suggests that no causal connection exists between the breach of duty and the occurrence of the event.      [Emphasis added]

Often little is required to discharge such evidentiary onus.  This is certainly so in cases where, for example:

·               as evidenced by conduct immediately preceding occurrence of damage, the plaintiff demonstrates a disposition against acting appropriately.[30]

·               the conduct of third parties need be proved in response to a hypothesis of no breach.   In Gold Ribbon (Accountants) Pty Ltd (in liq) v Sheers,[31] in a case of breach of duty by a company director that required  consideration as to how apt conduct would have impacted on the decisions of third party employees in granting loans, Keane JA wrote:

[279] In bearing in mind the continued presence of Austide, Howes and Sheers as the respondent’s decision-makers, it is necessary to acknowledge the uncertainties inherent in any assessment of the likely conduct of human beings in a hypothetical situation. In Fink v Fink, Dixon and McTiernan JJ cited with approval the observation of Vaughan Williams LJ that:

There are cases, no doubt, where the loss is so dependent on the mere unrestricted volition of another that it is impossible to say that there is any assessable loss resulting from the breach.

[280] … In the upshot, however, the position is that there was simply no evidence which would have enabled the trial judge to conclude that more explicit loan procedures, or proper supervision by the appellant as a non-executive director, would have led to different decisions in relation to the improvident loans.

[281] It will often be the case that a plaintiff will not be able to adduce direct evidence of the likely behaviour of a third party where proof of causation depends on the behaviour of that third party in hypothetical circumstances. It does not follow that a plaintiff will, as a result, fail to make out his or her case on the balance of probabilities. An inference may often properly be drawn as to the likely behaviour of a third party in hypothetical circumstances. The third party’s self interest may point in a particular direction, or the third party’s conduct may be objectively predictable as, for example, when a court determines a legal dispute.   In the present case, there are no such objective considerations which might support an inference in the respondent’s favour as to the behaviour of Austide or Sheers and Howes.

See the recent decision in Wolters v The University of the Sunshine Coast.[32]

Recently also, in Cowen v Bunnings Group Limited,[33] the issue for adjudication in an employment case was the causal nexus between an admitted breach of employment duty in the plaintiff cleaning up a pile of fertiliser spoil, and a condition with which she was diagnosed days later, namely pneumococcal meningitis.  The defendant’s expert witnesses conceded a nexus was possible but unheralded in medical practice and unlikely.  The defendant adduced evidence of other possible causes, namely the local atmospheric conditions due to ore refining work, and the plaintiff’s general health issues including that she was a smoker and was allegedly suffering a heavy cold at the time of exposure. 

Finding the admitted negligent event was the cause of the meningitis, Wilson J wrote:

[34] To the layperson, the temporal connection is something which is striking, and not easily dismissed. So, too, is [the plaintiff] Ms Cowen’s description of the volume, the intrusive nature, and the immediate unpleasant effects of the dust — i.e., the extreme conditions in which she worked for over two hours, and their immediate and continuing unpleasant effects.

[35] These are things which suggest a ‘… presumptive inference which this sequence of events would naturally inspire in the mind of any common-sense person uninstructed in pathology’: Adelaide Stevedoring Co Ltd v Forst [1940] HCA 45; (1940) 64 CLR 538, per Rich ACJ at p. 563 — i.e., they raise a powerful impression, in the mind of a layperson, that a causal connection is likely to exist.

…

[38] As Spigelman CJ observed in Seltsam, the legal concept of causation requires the court to approach the matter in a distinctly different manner from that which may be appropriate in either philosophy or science, including the science of epidemiology. The fact that medical science has not recorded a similar course of infection does not mean that it has not happened — or, importantly for present purposes, in a case where there is medical evidence indicating it is on one view quite possible and, on another, that it is not impossible or implausible, that it could not have occurred.

[39] The compelling features pointing to a causal connection are, firstly, the strong relationship in time between one event, and the other. The second is the nature of the material to which the plaintiff was exposed and the duration of exposure which, on any view, was serious and unpleasant and, in particular, caused immediate and prolonged upper respiratory tract symptoms. Dr McCormack thought the temporal connection weighed against coincidence, and that is also, again compellingly, the common-sense conclusion. The absence of similar examples in the literature cannot mean, as Drs Mitchell and Bartley had to concede, that the internal physical process he postulated is improbable or, in their words, implausible.

…

[68] While other causes had been advanced as possibilities, one (a pre-existing illness) is exploded by the evidence, and all the others involve such a high degree of coincidence — and, indeed, awfully bad luck — that they are considerably less plausible, to a degree which means that the attribution of causation to them would, with respect to the doctors, defy common sense.  [Emphasis added]

Conclusion:

The jurisprudence canvassed herein underscores the need for proper pleading, coupled with intensive evidentiary and tactical preparation for trial.

The ultimate focus must be upon persuasion of the court.  The plaintiff seeks  to bring that persuasion to fruition in respect of the liability case pleaded.  In contrast, the defendant, at the least, seeks to have the court left in doubt as to whether the plaintiff has proved that case.

Neither party ought lose sight of the fact that while the persuasive onus remains always on the plaintiff’s shoulders, the evidence led, if it grounds a prima facie inference on any factual or ultimate issue, may shift an evidentiary onus (or tactical burden) to the defendant.  That compels the adducing of evidence to repel the prima facie inference established on that issue.  Such tactical burden remains constantly in shift with the passage of evidence.

In this sphere, like others in litigation, it is worth remembering that good advocacy is all about making it as easy as possible for the court to find for the advocate’s client.

R J Douglas QC

Footnotes