STATE OF NEW SOUTH WALES v BURTON

CATCHWORDS: NEGLIGENCE - police officer shot at during siege and developed posttraumatic stress disorder - whether reasonably foreseeable risk of psychiatric harm - whether State breached its duty of care by not providing proper psychiatric and psychological treatment and counselling - whether breach of duty caused loss - whether breach of duty materially contributed to severity and duration of PTSD - whether breach of duty caused loss of a chance to reduce severity and duration of PTSD - contributory negligence

LEGISLATION CITED: Law Reform (Miscellaneous Provisions) Act 1946 (NSW), s 5(1)(c)

Athey v Leonati [1996] 3 SCR 458 Bonnington Castings Ltd v Wardlaw [1956] AC 613 Dillingham Constructions Pty Ltd v Steel Mains Pty Ltd (1975) 132 CLR 323 Dorset Yacht Co v Home Office [1970] AC 1004 Gregg v Scott [2005] 2 WLR 268 Hatton v Sutherland [2002] 2 All ER 1 Hole v Hocking [1962] SASR 128 Holtby v Brigham & Cowan (Hull) Ltd [2000] 3 All ER 421 Koehler v Cerebos (Aust) Limited [2005] HCA 15; (2005) 79 ALJR 845 Malec v J C Hutton Pty Ltd (1990) 169 CLR 638 CASES CITED: Middleton v Melbourne Tramway and Omnibus Co Ltd (1913) 16 CLR 572 Naxakis v Western General Hospital (1999) 197 CLR 269 Olympic Holdings Pty Limited v Lochel [2004] WASC 61 Purkess v Crittenden (1965) 114 CLR 164 Rufo v Hosking (2004) 61 NSWLR 678 Savini v Australian Terrazzo & Concrete Co Pty Ltd [1959] VR 811 Sellars v Adelaide Petroleum NL (1994) 179 CLR 332 Seltsam Pty Ltd v Ghaleb [2005] NSWCA 208 Smith v Leech Brain & Co Ltd [1962] 2 WLR 148 Watts v Rake (1960) 108 CLR 158 Wilson v Peisley (1975) 50 ALJR 207

PARTIES: State of New South Wales (Appellant) Christopher Burton (Respondent)

COUNSEL: P. Menzies QC/S. Woods - Appellant M. Joseph SC/I. Butcher - Respondent

SOLICITORS: Crown Solicitor - Appellant Oates & Smith - Respondent

IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 41016/04 DC 9889 of 2001

SPIGELMAN CJ BASTEN JA HUNT AJA

10 February 2006 STATE OF NEW SOUTH WALES v CHRISTOPHER BURTON The State of NSW appeals against a decision of the District Court awarding damages to Mr Burton. Mr Burton was employed as a marksman in the Tactical Response Group, a specialist unit in the NSW Police force. During the course of his duties, Mr Burton was fired upon, but not hit, during a siege at a farm. The respondent developed posttraumatic stress disorder (PTSD) as a result of that incident. The District Court held that the State was negligent in failing to provide Mr Burton with proper psychiatric and psychological treatment and counselling for him with respect to his exposure to stress at the siege. The issues for determination by the Court of Appeal included whether: (i) there was a reasonably foreseeable risk of psychiatric harm to Mr Burton in relation to the incident and whether the NSW Police breached their duty of care; and (ii) the breach caused any loss to Mr Burton. Held in relation to (i): By Basten JA (Spigelman CJ and Hunt AJA agreeing): The State breached the duty of care owed to Mr Burton. The kind of psychiatric injury that Mr Burton suffered was reasonably foreseeable. There was ample evidence to support the conclusion that the Police Service itself had identified the risk of psychological or psychiatric harm to an officer who had been involved in an incident such as where shots were fired at that officer: at [41]. Koehler v Cerebos (Aust) Ltd (2005) 79 ALJR 845 applied. Held in relation to (ii): By Spigelman CJ (Hunt AJA agreeing):

1. The evidence as to the possibility that early intervention would have reduced the risk of Mr Burton suffering PTSD at all was at best tangential and provide no evidentiary basis for an inference that such contribution to incurring the condition as was made by the State's breach of duty was a material contribution: at [21].
2. The PTSD was not caused by the failure to have counselling, or take other ameliorative steps. It was caused by the shooting. The relevant loss was a loss of a chance of a better outcome. The matter should be remitted to the District Court to assess the extent of the loss of the chance: at [24] - [28]. Sellars v Adelaide Petroleum NL (1994) 179 CLR 332; Olympic Holdings Pty Limited v Lochel [2004] WASC 61 and Rufo v Hosking (2004) 61 NSWLR 678 referred to. By Basten JA (dissenting in part):
3. There was sufficient evidence to establish on the balance of probabilities that the severity and duration of PTSD could have been reduced by the provision of early psychological intervention. The failure of the State to so provide materially contributed to his psychiatric condition: at [65] - [66].
4. Since it was likely that Mr Burton would have suffered a level of PTSD in the absence of the State's negligence, the trial judge should have apportioned the harm done as between the shooting and the conduct of senior police officers in its aftermath: at [80]. Purkess v Crittenden (1965) 114 CLR 164; Watts v Rake (1960) 108 CLR 158; Malec v J.C. Hutton Pty Ltd (1990) 169 CLR 638; Wilson v Peisley (1975) 50 ALJR 207; Dillingham Constructions Pty Ltd v Steel Mains Pty Ltd (1975) 132 CLR 323 referred to. IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 41016/04 DC 9889 of 2001

SPIGELMAN CJ BASTEN JA HUNT AJA

10 February 2006 STATE OF NEW SOUTH WALES v CHRISTOPHER BURTON Judgment 1 SPIGELMAN CJ: The facts and issues are set out in the judgment of Basten JA, which I have read in draft. 2 I agree with Basten JA that the appeal with respect to the findings of foreseeability of risk should be dismissed. On the authority of Koehler v Cerebos (Aust) Limited [2005] HCA 15; (2005) 79 ALJR 845 esp at [35], set out by Basten JA, the focus must be on the duty owed to the particular employee. 3 Because of the Respondent's special skills, training and experience the Appellant's knowledge, reflected in the Major Incidents Policy with respect to police counselling, set out by Basten JA, would not have been sufficient to establish foreseeability in the present case. However, the knowledge reflected in the S.W.O.S. Guidelines, also set out by Basten JA, are applicable to the Respondent as a member of the Tactical Response Group. 4 Foreseeability was established on his Honour's primary findings of fact. These findings are set out by Basten JA. The trigger in the S.W.O.S. Guidelines was satisfied. I refer particularly to the conversation after the incident at Coolabah with Inspector Ruming and the evidence of Sergeant Bonner. 5 The issue on which I differ from Basten JA is with respect to identifying the damage which flowed from the Appellant's breach. 6 His Honour concludes that the evidence, accepted by Puckeridge DCJ, that the Appellant's omissions affected the length and severity of the Respondent's Post Traumatic Stress Disorder (PTSD) leads to the conclusion that the Appellant made a material contribution to the Respondent's condition. In my opinion, on the evidence and the findings, it is necessary to distinguish between the Respondent having PTSD (for which the Appellant was not responsible) and the loss of possibility of a better outcome in terms of length and severity (for which the Appellant was responsible). 7 The rival submissions in this Court were, in substance, based on alternative interpretations of his Honour's reasons. The Appellant submitted that his Honour's findings should be understood as concluding that the Respondent would have suffered PTSD after the shooting incident in any event and that the Appellant's conduct led to no more than the loss of a chance of a better outcome. The Respondent submitted that his Honour found that the Appellant's acts and omissions made a material contribution to the Respondent suffering PTSD. 8 The Appellant's grounds of appeal included a ground that his Honour should have found that any breach did not make a material contribution to the Appellant's PTSD. Another ground asserted that damages should have been assessed on a loss of a chance basis. In my opinion these grounds should be upheld. 9 There was no suggestion that the Appellant was in any way responsible in tort for exposing the Respondent to the shooting incident at Coolabah. The evidence is overwhelming, indeed unanimous, that it was the Respondent's exposure to small arms fire on that occasion that was the cause of his psychiatric condition. The issue to be determined was whether the Appellant's failure to take steps, particularly to ensure that the Respondent received proper counselling and treatment, was a breach of duty and what damage flowed from that breach. 10 In my opinion, this case does not give rise to the evidentiary issue identified in Watts v Rake (1960) 108 CLR 158 and Purkess v Crittenden (1965) 114 CLR 164. This is a case like Wilson v Peisley (1975) 50 ALJR 207 esp at 219 in which the existence of a pre-existing condition and of its propensity for harm to the respondent was made out at trial. As in Malec v JC Hutton Pty Ltd (1990) 169 CLR 638, the injury caused by the Appellant's tortious conduct fell to be assessed on the basis that "the damage would have occurred in any event as the result of … events for which the defendant is not liable" (p 640). 11 After Puckeridge DCJ had set out the relevant evidence, particularly the medical evidence, his Honour expressed the critical finding in the following passage: "On the medical evidence before me I consider that it is probable that had debriefing and counselling occurred after the shooting incident at Coolabah in accordance with protocol, the risk of the plaintiff developing PTSD would have been minimised. I prefer the view of Dr Wright, and consider that the delay that occurred in the plaintiff accessing appropriate psychological and psychiatric treatment probably contributed to the development and persistence of the plaintiff's PTSD condition." 12 In the passage the words in the last sentence "the development and persistence" of PTSD refer, respectively, to an increased risk of PTSD occurring at all ("development") and to an increased severity and duration of the PTSD once it had occurred ("persistence"). The word "minimised" appears also to refer to the increased risk. This interpretation is supported by the passage in his Honour's reasons, shortly before this conclusion, where he sets out and summarises the relevant evidence of Dr Wright, which his Honour accepted: "In a report of 21st April 2001, Dr Wright stated that it was his opinion that if there had been available psychiatric and/or psychological interventions such as counselling or debriefing such interventions could have alleviated some of Mr Burton's complaints or reduced the risk of developing PTSD. He stated such interventions may not have prevented PTSD occurring but could have reduced its severity and/or duration. In a further report of 30 January 2004, Dr Wright stated that in his opinion the incident at Coolabah was a clear causal factor in the plaintiff's development of PTSD and the delay in accessing appropriate psychiatric and psychological treatment probably further contributed to the development and persistence of the plaintiff's condition." 13 In these passages, his Honour makes no reference of any character to the degree to which the conduct by way of omission on the part of the State made a 'contribution' to the development of the Appellant's PTSD or the degree to which the "risk" of that occurring increased. In another case it may be appropriate to infer that his Honour made a finding that the degree of contribution was of sufficient significance to satisfy the description of a "material contribution". I would not, however, draw that conclusion in this case. That is because of the strength of the evidence, which his Honour also set out, that the cause of the PTSD was the shooting incident itself. 14 I have set out above his Honour's summary of the pertinent evidence of Dr Wright. That summary indicates that Dr Wright gave no evidence of any character on the basis of which the Court could assess the degree of contribution or the degree of increased risk. There was evidence from Dr Wright that the Appellant's omissions made some contribution to the development of the PTSD itself. However, there was, in my opinion, no evidence which could justify an inference that that contribution was a material contribution. Furthermore, when one reads the reference to an increased "risk" of developing PTSD in Dr Wright's reports in their full context there is nothing to suggest that that increased degree of risk was significant. 15 In Dr Wright's first report of 28 July 2000, to which his Honour does not expressly refer but which is consistent with the subsequent reports and is, indeed, reaffirmed in them, Dr Wright said: "In my opinion, the Posttraumatic Stress Disorder experienced by Mr Burton arose as a result of the incident at Coolabah in December 1998. However, it is likely that a requirement for Mr Burton to work prolonged shifts even after this incident exacerbated his condition . It is also likely that his perception of an insensitive and accusatory management further exacerbated his condition and that his involvement in a similar incident two weeks later (whilst still feeling unwell) further exacerbated his condition . Therefore I would conclude that the actual traumatic incidents contributed significantly to his PTSD but it is likely that the requirement of working long hours and insensitive management and a return to similar dangerous incidents while still unwell further contributed to the condition ." [Emphasis added] 16 Dr Wright went on to make reference to his opinion that there was a failure to adequately assess and monitor the Respondent's condition and that further treatment "may have reduced the overall severity of his condition". The fact that the conduct of the Appellant was a matter of exacerbation, rather than causal of the condition, was emphasised in the succeeding passage of this report: "In essence, the fact that Mr Burton was required to continue working at the original incident despite feeling unwell, the fact that he was inadequately debriefed and monitored, the fact that his referral for appropriate psychological treatment was delayed, and the fact that he perceived his managers to be unsympathetic and disbelieving of his distress all exacerbated his PTSD but the PTSD was caused by his exposure to the life-threatening stressor . Even if all these issues had been addressed he may still have developed a Posttraumatic Stress Disorder, but in my opinion it would not have been as severe as his recovery would have been speedier and more complete." [Emphasis added] 17 In his subsequent report of 21 April 2001, Dr Wright reiterated his conclusions in the earlier report about the conduct of the Appellant which "exacerbated" or "further contributed" to the Respondent's condition. He then said: "It is my belief that Mr Burton's illness (PTSD) was caused by a shock in the sense of a sudden sensory perception, which occurred in the form of being fired upon and believing that he would die." [Emphasis added] 18 He then went on to say, in the passage relied upon by Puckeridge DCJ: "I believe that there would have been available psychiatric and/or psychological interventions such as counselling, or debriefing which could have alleviated some of Mr Burton's complaints or reduced the risk of developing a PTSD. These treatments may not have prevented a PTSD occurring but could have reduced its severity and/or duration . In my opinion, if Mr Burton had been removed from the stressful situation (instead of being required to work prolonged hours) then given appropriate and adequate formal and informal debriefing, he may still have developed some symptoms of a PTSD but I believe the condition would not have been as severe. It is also probable that early intervention with appropriate psychiatric review and/or treatment would also have reduced the severity and duration of the PTSD. As stated in my original report, I believe that the fact that Mr Burton was required to continue working at the original incident despite feeling unwell, the fact that he was inadequately briefed and monitored, the fact that his referral for appropriate psychological treatment was delayed, and the fact that he perceived his managers to be unsympathetic and disbelieving of his distress all exacerbated his PTSD, but the PTSD was caused by his exposure to the life-threatening stressor . If all of these issues had been addressed he may still have developed a PTSD, but in my opinion it would not have been as severe and his recovery would have been speedier and more complete. If Mr Burton had been given sufficient instruction, education or warning about the likely psychological consequences of exposure to severe traumatic incidents this may have allowed him to recognise the significance of his symptoms at an early stage and present himself for appropriate treatment. Early recognition and treatment would have been likely to reduce the severity and/or duration of Mr Burton's illness ." [Emphasis added] 19 In a further report of 27 September 2001, Dr Wright referred to the failure to have psychological assessments of, or to monitor, the Respondent's condition after the incident at Coolabah and added: "It is not possible for me to say whether such an early diagnosis and intervention would have altered the subsequent course of Mr Burton's condition, but there is a strong possibility that early diagnosis and intervention of such conditions does reduce the subsequent severity, and duration of such problems. It is also likely that early diagnosis and removal from full operational duties would have reduced the exacerbation of his condition associated with continuing to work in a high-risk area where there is a constant potential for exposure to dangerous and even life-threatening incidents. This removal from such an environment would have been likely to reduce the severity and duration of Mr Burton's symptoms of a Posttraumatic Stress Disorder." [Emphasis added] 20 Finally, in his report of 30 January 2004, to which his Honour refers, Dr Wright concluded: "In my opinion, the incident in December 1998 was a clear causal factor in his development of PTSD, but the delay in accessing appropriate psychiatric and psychological treatment probably further contributed to the development and persistence of his condition ." [Emphasis added] 21 The thrust of Dr Wright's evidence is clearly directed to establishing that the omissions on the part of the Appellant were such as to increase the severity and duration of the PTSD which was caused by the shooting incident itself. The references to the possibility that early intervention would have reduced the risk of the Respondent suffering PTSD at all are at best tangential and provide no evidentiary basis for an inference that such contribution to incurring the condition as was made by the Appellant's breach of duty was a "material contribution". 22 Indeed, I do not believe, on reading the reports as a whole, that Dr Wright intended to advance any such proposition. 23 Insofar as Puckeridge DCJ adopted the precise terminology of Dr Wright - terminology which made no reference to the degree of "risk" or of "contribution" - then his Honour should be understood as adopting the evidence of Dr Wright. That evidence cannot be interpreted, in my opinion, to suggest that any such contribution was material. Alternatively, if his Honour did intend to draw any such conclusion, then there was no proper evidentiary basis for it. 24 On either approach, the end result is that damages were assessed on an inappropriate basis. The matter should be remitted to the District Court for damages to be assessed on a loss of a chance basis. 25 The PTSD was not caused by the failure to have counselling, or take other ameliorative steps. It was caused by the shooting. The relevant loss in this case is the loss of a chance of a better outcome. The focus of attention must be on the extent to which the Respondent's condition would or could have been improved had earlier counselling been provided. 26 Any such reassessment should not extend to the loss of a chance that the Respondent would not have suffered PTSD at all. I do not understand Dr Wright to advance the proposition that that was a significant factor. 27 The onus was throughout on the Respondent, as plaintiff, to establish the existence and extent of the loss of the chance. On the basis of his Honour's findings it appears that there was a loss of such a chance and that, as a matter of causation, the Respondent has suffered some loss or damage. (See e.g. Sellars v Adelaide Petroleum NL (1994) 179 CLR 332 at 355; Olympic Holdings Pty Limited v Lochel [2004] WASC 61 at [122]-[123]; Rufo v Hosking (2004) 61 NSWLR 678 at 680.) 28 His Honour made no assessment of the extent of the loss of the chance. No submissions were made in this Court on the appropriate assessment. This Court is in no position to make such an assessment. There is a significant dispute on the evidence of the medical witnesses as to the efficacy of early intervention. Further consideration of this evidence should form part of any such assessment. The matter should be remitted to the District Court to assess the loss of a chance of a better outcome. 29 I agree with the reasons of Basten JA on the issue of contributory negligence. 30 I agree with the orders proposed by Basten JA except order 2. Order 2 should be made in the following form: "Remit the matter to the District Court for assessment of the loss of the chance of a better medical outcome." 31 BASTEN JA: In late 1998 Mr Burton ("the Respondent") was employed as a marksman in the Tactical Response Group ("the TRG"), being a specialist unit within the New South Wales Police Service. (It was later renamed the Tactical Operations Unit.) 32 On 2 December 1998, the Respondent, and a number of other officers in the TRG, were deployed on a farm property at Coolabah in northern New South Wales where a farmer was holding his six-year-old son as hostage within the farmhouse, from which he was firing shots. The Respondent had taken up a position behind a tree, but his position was identified by dogs released by the farmer. Several shots were fired at the Respondent. He continued to perform duties at Coolabah until the offender was arrested the next day. 33 In May 1999, he saw a psychologist working with the Police Service. On 4 June 1999 he filed a claim for benefits as a result of being "hurt on duty", the injury being identified as post-traumatic stress disorder. He left the Police Service in November 1999. 34 On 20 February 2001 the Respondent commenced proceedings in the District Court against the State of New South Wales ("the Appellant"), claiming damages for negligence arising from the failure of the State through relevant officers in the Police Service to provide proper psychiatric and psychological treatment and counselling for him with respect to his exposure to stress at Coolabah. He was successful at trial and obtained a judgment against the Appellant for an amount of slightly less than $400,000. In this Court the Appellant sought to challenge the decision below on four broad bases, namely:

(a) the finding that there was a reasonably foreseeable risk of psychiatric harm in relation to the experience faced by the Respondent whilst on duty at Coolabah;

(b) the finding that, if there were such a risk, relevant officers in the Police Service, in breach of a duty of care, failed to take those steps which were reasonable and appropriate in the circumstances;

(c) to the extent that other steps should reasonably have been taken, such failure was not shown to have caused loss to the Respondent, and

(d) even if the Appellant were liable to the Respondent in damages, the reduction of the award by 10% on account of contributory negligence was manifestly inadequate.

It is convenient to address these issues separately although, as will appear, to a degree they interlock.

Foreseeability of risk 35 According to the Respondent, the issue of foreseeability was not disputed at trial and, indeed, could not reasonably have been disputed. It was not in doubt that the Appellant, as the employer of the Respondent, owed him a duty of care in relation to his working environment. Further, it was, the Respondent suggested, beyond doubt that an officer at whom shots are fired whilst he is in a relatively exposed position behind a tree on otherwise open ground, is subjected to stress and faces a real risk of psychiatric, as well as physical, injury. 36 The Appellant's case was placed squarely on the specific point that, whilst a general duty of care existed and, in many circumstances, psychiatric harm could be foreseen, it was necessary to determine each case on its own facts. The Respondent, it was asserted, was not untrained, inexperienced or otherwise naïve about the circumstances in which he found himself. He had been a member of the TRG since about 1985, was trained as a marksman and armed accordingly. The Appellant said that the correct approach, which was not adopted by the trial judge, was that identified in the joint judgment in the High Court in Koehler v Cerebos (Aust) Ltd [2005] HCA 15; (2005) 79 ALJR 845, at [35] in the following terms: "The duty which an employer owes is owed to each employee. The relevant duty of care is engaged if psychiatric injury to the particular employee is reasonably foreseeable. That is why, in Hatton [ v Sutherland [2002] 2 All ER 1 at 13[23]] the relevant question was rightly found to be whether this kind of harm to this particular employee was reasonably foreseeable. And, as pointed out in that case, that invites attention to the nature and extent of the work being done by the particular employee and signs given by the employee concerned." 37 The test identified by the Appellant was one that should properly have been applied by the trial judge, subject to any concessions made by the Appellant during the trial. Whilst it seems that the case for the Appellant was not put at trial in precisely the way in which it is now formulated, there was clearly a dispute as to the scope of the duties owed by senior police officers to the Respondent and whether they had been breached, in all the circumstances. However, the trial was run, and judgment delivered in the District Court on 30 September 2004, without the assistance of the reasoning of the High Court in Koehler, in which judgment was delivered on 6 April 2005. In Koehler at [19], the joint judgment noted: "Because the appellant's claim was framed in negligence, and because her claim was brought against her employer, it may be thought necessary to have regard only to the well-established proposition that an employer owes an employee a duty to take all reasonable steps to provide a safe system of work. From there it may be thought appropriate to proceed by discarding any asserted distinction between psychiatric and physical injury, and then focus only upon questions of breach of duty. Questions of breach of duty require examination of the foreseeability of the risk of injury and the reasonable response to that risk in the manner described in Wyong Shire Council v Shirt . But to begin the inquiry by focusing only upon questions of breach of duty invites error. It invites error because the assumption that is made about the content of the duty of care may fail to take fundamental aspects of the relationship between the parties into account."

It would appear that both the parties and the Court below may have approached the matter in the manner disapproved in Koehler . 38 The finding made by the trial judge (at p 43) was that "the defendant failed to take reasonable care to minimise the foreseeable risk of police officers in the Tactical Operations Unit, including the plaintiff, developing PTSD". The failure to separate the various elements of the legal question had the potential to give rise to error, in the way the Appellant now asserts. Nevertheless, whether it did in fact give rise to error is a question which can only be answered by reference to the particular circumstances of the case. In Koehler, the plaintiff had been a "part-time merchandising representative". The tasks assigned her were, as she explained to her employer, well beyond the scope of what could be achieved within the limited hours of her employment. She complained of that fact on a number of occasions. Despite that, she gave no "external signs of distress or potential injury, and such a risk was not apparent from the nature of the work itself". Those facts are, however, quite different from the circumstances faced by the Respondent in the present case. Indeed, in a sense, the position is reversed: work in the TRG was of a kind which might be extremely stressful to ordinary members of the public. So much so, the Appellant suggested, that it was not reasonably foreseeable that psychiatric injury would flow to those specially trained for and experienced in that kind of work and that even protocols applicable to other police officers should not be applied to the TRG. 39 Given the way in which the case appears to have been run, I am not persuaded that this complaint should be accepted. That is not to say that its component parts were not raised at trial, nor that they cannot be addressed in this appeal. Thus, the Appellant clearly raised an issue as to what, in all the circumstances, its duty to the Respondent required of its senior officers in the circumstances of the case, put in terms of an absence of any breach of duty, and relied upon the particular training and experience of the Respondent as demonstrating an absence of causal connection between the incident at Coolabah and any psychiatric condition. 40 The reason why the complaint should be rejected on its merits is that the evidence demonstrated in unequivocal terms that the Police Service had, at least by 1991, identified the nature of the risk faced by its officers in circumstances of a kind within which the Coolabah incident would fall. Thus, on 25 March 1991, a Commissioner's circular had been issued under the heading "Major Incidents Policy". The circular made the following comments under the heading "Police Counselling": "Where police officers are subjected to trauma or undue stress associated with a major incident, it is mandatory that counselling be provided and that the services of the medical and support services branches of the Police Service be used. Commanders should be alert to the symptoms of trauma and stress."

The Appellant sought to draw support from this document as one identifying a general policy and noting, by reference to the sentence following the last passage set out above, that it also required that further reference be made to the appropriate section of "the S.W.O.S. guidelines" which presumably applied to the TRG. The inference to be drawn, the Appellant argued, was that members of the TRG should not have been treated as subject to some mandatory requirement for counselling because their routine work involved major incidents. By contrast, the relevant guideline applying to the Tactical Operations Unit (and by inference the TRG before it) read as follows: "If as the result of an operation a member of the Police Service appears affected in such a manner that indicates that he/she may require welfare assistance, the designated Operations Commander shall notify the Police Welfare Branch and have an officer attend and provide necessary assistance." 41 In addition, the Police Service had instituted a "peer support program" involving management of "critical incident stress", and involving a training program which the Respondent himself had attended. This identified, in both psychological and everyday terminology, the nature of stress, mechanisms for managing stress and symptoms of what were differentiated as the "normal response" and the "pathological response" to stressors. In short, there was ample evidence before the trial judge to support the conclusion that the Police Service itself had identified such "critical incidents" as involving a risk of psychological or psychiatric harm to officers who might be involved. The class of such incidents included those where shots had been fired at an officer. Even if there were error in the manner in which this issue was dealt within the judgment below, the conclusion that the Respondent had established on the balance of probabilities the foreseeability of the kind of psychiatric injury which he suffered should be accepted. This aspect of the Appellant's challenge fails.

Breach of duty 42 The second broad category of challenge to the judgment below requires the identification of those steps which the Respondent had asserted at trial should have been taken and were not. 43 As already noted, the Appellant's case was that, as a member of the TRG, even if there were a foreseeable risk of psychiatric injury, it was both impracticable and inappropriate to require all officers to attend counselling or psychological assessment, every time they participated in a "critical incident". Rather, what was required was that a commanding officer take steps appropriate to the individual officer and the individual circumstances, as the need arose. To that end, the Respondent had to establish that the officer in charge at Coolabah, Inspector Ruming, or one of his senior subordinates, was aware that the Respondent was distressed and had failed to take appropriate action. On the facts, it was argued, those conditions had not been satisfied. 44 The case for the Respondent, assuming that mandatory counselling in all circumstances was not required, was, in effect, threefold. First, counselling should properly have been mandatory, once the obligation was engaged, because simply to provide an opportunity, given the culture of a force such as the TRG, would not have been sufficient to ensure that those in need obtained the necessary assistance. Secondly, if counselling were not mandatory after all critical incidents, but depended upon the perceptions of senior officers, those officers should have the training to recognise symptoms of stress and precursors to psychiatric injury. Thirdly, he said that the relevant officers were indeed aware of his distressed state. 45 Dealing first with the third matter, the Respondent testified in relation to two conversations which he had at Coolabah, shortly after the incident during which shots were fired at him. Immediately the gunman had turned his weapon in another direction, the Respondent had moved to a different position, behind a large earth dam, which gave him better protection. Shortly thereafter, he was driven back to the command post, where he spoke to Senior Sergeant Jennings. There is no doubt that there was a conversation with Sergeant (now Inspector) Jennings during which the Respondent had described what had happened to him. The Respondent said he was "distressed"; Mr Jennings said that he thought that the Respondent was "angry" that shots had been fired in his direction, and that he was "excited and annoyed". After he had an opportunity to calm down, Mr Jennings asked the Respondent whether he wanted to return to a field position or stay at the command post and said that the Respondent had agreed to return to the field. He remained there until 6pm in the evening, at which stage he had been on duty for some 23 hours. He then had a rest for eight hours and returned to the field at 2am the following morning. 46 At some stage during that morning the offender left the farmhouse and was arrested. The Respondent spoke to Inspector Ruming whilst he was in the field and took the Inspector to the position he was in when fired upon. He said that, in the course of telling the Inspector what had happened he had said: "You wanna be careful boss, I might wig out over this one."

He further gave evidence that Inspector Ruming replied: "Don't think you're going to pull that one over me Burto. If you think you can pull the wool over my eyes I'll march you straight down to David Mutton and he will shorten you right up."

(Mr Mutton was the head of the Police Psychology Unit.) 47 Inspector Ruming denied that any such conversation had taken place, but the trial judge accepted the Respondent's evidence. 48 One of the other senior officers at Coolabah was Sergeant Bonner, who also gave evidence of the Respondent's condition. 49 The evidence accepted by the trial judge may sufficiently be identified from the following findings: judgment at pp 12-14. "[Inspector Ruming] regarded the incident at Coolabah as a major incident. The Inspector himself assessed that there was a risk that the plaintiff could suffer psychological symptoms as a result of being shot at whilst at Coolabah. Sergeant Bonner had been a marksman employed to relieve the plaintiff at the farmhouse. He said that when he arrived at the position taken up by Mr Burton, the plaintiff told him about what had happened, Sergeant Bonner observed that at the time the plaintiff's hands were shaking, his eyes looked like dinner plates, and he was talking very quickly. The plaintiff appeared to Sergeant Bonner to be nervous and unable to relax. Sergeant Bonner was of the opinion that the plaintiff was quite upset at what had occurred. … He said that when the plaintiff returned to relieve him … he did not appear as jittery, but had dark rings under his eyes, his complexion was pale and he looked very withdrawn. … Sergeant Bonner, upon being relieved by the plaintiff, returned to the command post and spoke to Sergeant Jennings. He said that he told Sergeant Jennings there was no way that the plaintiff should have been back in the field location. … I accept the evidence of Sergeant Bonner that he did have a conversation as to what he observed of the plaintiff and that he did not consider that the plaintiff ought to have been sent to relieve him as a marksman." 50 The trial judge held that neither Inspector Ruming nor Sergeant Jennings took any steps to ensure that the Respondent obtained counselling, nor restricted the kinds of duties he might undertake in the immediate future, nor took any steps to monitor his condition. Indeed, less than two weeks later, he was sent as a member of the TRG to Nimmitabel, again as a marksman to deal with an incident at an isolated farm property. The judge gave the following summary of the Respondent's evidence as to what happened on that occasion (at p 17): "Whilst at the location at Nimmitabel a fellow police officer suddenly appeared in the vicinity of the plaintiff with a shotgun. At the time the plaintiff said that he was not aware that the person was a fellow police officer. The plaintiff said that the appearance of the person with a shotgun had a bad effect upon him and he had to drop his rifle and run. He said that he was shaking and found it very hard to control himself."

There is some uncertainty as to whether his Honour accepted that the Respondent had demonstrated a strong reaction at Nimmitabel. He concluded (at pp 32-33) that the Respondent did not drop his rifle and run, because had that occurred, he was satisfied that Sergeant Navin, who was a peer support officer present at the time, would have observed and remembered that event. 51 Whether the general principle, set out in the Commissioner's circular, and requiring automatic referral for counselling, or the specific guidelines in relation to the TRG, requiring referral where the commanding officer perceived signs of distress, applied, the requirement was engaged in either case. The trial judge concluded that Inspector Ruming was under an obligation, if not to arrange for mandatory counselling to be provided, at least, being aware that the Respondent may have required welfare assistance, to notify the Police Welfare Branch and have an officer attend and provide the necessary assistance. He failed to do either. However, his Honour also held: "I consider that the evidence of what treatment and advice that would have been given, had the plaintiff been referred for psychological counselling following the Coolabah incident, is so hypothetical as to amount to speculation. In the absence of specific action to refer the plaintiff to Psychology Unit I do not consider that the plaintiff would have availed himself of the welfare facilities within the department as at the time he was required to attend at Nimmitabel as a marksman. I accept the evidence of the plaintiff that as at that time the plaintiff was experiencing psychological symptoms as a result of the incident at Coolabah, but find on the probabilities that the plaintiff had decided to 'tough it out'." 52 The precise tenor of this conclusion is ambiguous. It seems that the second sentence merely accepts what in fact happened: namely that the Respondent did not voluntarily seek counselling at that time. The first and third sentences suggest that, even if he had been required to seek counselling, he would not voluntarily have revealed symptoms which demonstrated a psychological problem. (In part that was because he had an application for promotion pending at that time.) This finding becomes important in relation to the next question, namely whether a failure to refer the Respondent for counselling prior to the deployment at Nimmitabel had any causal connection with his later condition. 53 In relation to the first matter identified at [45], his Honour appears to have accepted that once counselling was identified as appropriate, it should have been mandatory. His Honour noted: "The plaintiff said that there was a culture in the Tactical Response Unit that after any catastrophic incident it was best 'to get back on the horse and ride'." 54 In relation to the second matter, his Honour did not expressly deal with the question as to whether senior officers were adequately trained to recognise stress and precursors to psychiatric injury, because of his satisfaction that Inspector Ruming was in fact sufficiently aware that the Respondent had been exposed to a relevant stressor and had been made aware of his distress. 55 The Appellant argued before the trial judge that the failure to refer was not a breach of duty, nor causative in the relevant sense, because "it is now accepted that debriefing per se is contra-indicated": Judgment at p 40. The Appellant called evidence to establish that "debriefing is either ineffective or harmful" in relation to the risk of post-traumatic stress disorder. There was, however, contrary evidence before the Court and his Honour accepted an alternative view and, as a result, held that the following particulars of breach of duty were made out (p 43). "a) Failing to ensure that the plaintiff was psychologically debriefed in accordance with protocol. b) Failing to monitor the plaintiff. No peer support officer was instructed to report any abnormal and/or unexpected behaviour of an officer involved in a shooting incident to the commander of the Tactical Operations Unit. c) Failing to specifically direct Sergeant Jennings to monitor the plaintiff. Had Sergeant Jennings been directed to specifically monitor the plaintiff it is probable that Sergeant Jennings would have directed other peer support officers to note any change in the plaintiff's behaviour and to report any such change to him. It is probable that Sergeant Jennings would have report any such change to Inspector Ruming. d) Failing to instruct the commander of the Tactical Operations Units that the classification of a critical incident was determined by the reaction of the officer involved. e) Failing to instruct the plaintiff of the benefit of debriefing and/or early psychological and/or psychiatric treatment following an incident where he is fired upon. f) Failing to instruct the commander of the Tactical Operations Unit that automatic contact with the psychology unit was to occur whenever a police officer was fired upon or shot at. g) Causing and/or permitting the plaintiff to delay seeking psychological and/or psychiatric treatment. The statement by Inspector Ruming as noted by the plaintiff [exhibit 3] did contribute to the plaintiff not seeking psychological and/or psychiatric treatment. The plaintiff was unaware of the benefit of early psychological and/or psychiatric treatment. h) Failing to refer the plaintiff for early psychological or psychiatric treatment following the shooting incident at Coolabah." 56 These findings involve at least three different elements. The first is a failure to provide a "psychological debriefing": par (a). A second is a failure to monitor: pars (b) and (c). A third is a failure to provide psychological or psychiatric treatment. In addressing the consequences of such failures, it would be necessary to ensure that the medical evidence adopts similar concepts. Thus, it may be important to know whether a particular practitioner would treat the first and third categories as different and to ensure that the medical evidence was directed to the particulars as found. 57 Each of the broad areas of complaint raised by the Appellant overlap and tend to merge, the one into the next. It is convenient to deal with other aspects of the argument concerning lack of breach of duty in the context of causation.

Causation 58 The argument in relation to causation both reaches back into the alleged absence of any breach of duty and forward into the assessment of damages. Its focus must be the medical evidence as to the effect of not referring the Respondent for counselling or psychiatric debriefing shortly after the incident during which he was shot at. Thus, on the one hand, if immediate counselling were not considered medically useful, there would be no obligation to provide it and the failure to obtain it for the Respondent could be seen not to constitute a breach of any appropriately formulated duty. On the other hand, if counselling were of assistance, then there would have been a breach of duty in failing to provide it, but a further question would arise as to the consequence of the breach. Finally, the medical evidence might support a conclusion that counselling would be useful in some circumstances or for some people, but not universally. Such a conclusion would give rise to a number of inter-related issues. 59 There was conflicting medical evidence before the trial judge as to the proposed counselling; there was uncertainty as to the time period envisaged by those who supported immediate counselling; there was doubt as to whether the Respondent would have participated usefully had such counselling been provided, and finally there was uncertainty as to the effect of such counselling even had it been provided promptly after the critical incident. The first issue addressed by the trial judge in relation to the correct conduct of the Appellant was the question of "debriefing", by which was meant a debriefing by a psychologist within 72 hours of the incident. The Appellant called evidence from Dr Julian Parmegiani, who expressed the opinion that "the latest recommendation by experts is that debriefing is either ineffective or harmful": Report, 11 February 2002, p 11. Dr Parmegiani continued: "Studies have shown that providing other types of psychological treatment to all people exposed to trauma does not prevent PTSD. A recent study by Bryant showed that treating some people after trauma is useful. His research found that people who develop significant symptoms of anxiety within the first month of a trauma benefit from cognitive behaviour therapy. This reduces the risk of developing PTSD. The study involved small numbers, and is yet to be replicated by other authors." 60 Dr Phillip Brown, also a consultant psychiatrist whose report was tendered by the Appellant, stated: "There is no hard evidence that direct debriefing prevents the onset of a PTSD and some evidence to suggest it can increase the symptoms in some individuals. Nevertheless, it is done, as it seems an appropriate thing to do for many other reasons. It shows support and advises where assistance might be sought should symptoms continue or develop." 61 The principal psychiatric evidence relied on by the Respondent was to be found in the reports of Dr Murray Wright, consultant psychiatrist. In a report dated 28 July 2000, Dr Wright expressed the following opinion (at p 5): "In essence, the fact that Mr Burton was required to continue working at the original incident despite feeling unwell, the fact that he was inadequately debriefed and monitored, the fact that his referral for appropriate psychological treatment was delayed, and the fact that he perceived his managers to be unsympathetic and disbelieving of his distress all exacerbated his PTSD, but the PTSD was caused by his exposure to the life-threatening stressor. Even if all these issues had been addressed he may still have developed a Posttraumatic Stress Disorder, but in my opinion it would not have been as severe and his recovery would have been speedier and more complete." 62 This opinion was confirmed in a subsequent report of 21 April 2001. On 21 September 2001 the Respondent's solicitors wrote to Dr Wright inviting answers to two questions, which answers were provided on 27 September 2001. (The letter identifying the questions appears not to have been in evidence.) The first question appears to have related to the possible results of assessment immediately following the incident. Thus he expressed the view, based on what the Respondent had told him, that had he been "examined following his participation in the incident … I believe such an assessment … would have revealed symptoms of an acute stress reaction, and that further monitoring of his condition over the following months would have revealed the development of a posttraumatic stress disorder". He was of the view that these diagnoses would have precluded him returning to full operational duties until the symptoms had resolved assuming, presumably, that the Respondent had sufficiently revealed his condition. However, Dr Wright continued: "It is not possible for me to say whether such an early diagnosis and intervention would have altered the subsequent course of Mr Burton's condition, but there is a strong possibility that early diagnosis and intervention of such conditions does reduce the subsequent severity, and duration of such problems. It is also likely that early diagnosis and removal from full operational duties would have reduced the exacerbation of his condition associated with continuing to work in a high-risk area where there is a constant potential for exposure to dangerous and even life-threatening incidents. This removal from such an environment would have been likely to reduce the severity and duration of Mr Burton's symptoms of a posttraumatic stress disorder." 63 The trial judge recounted parts of Dr Wright's evidence, as well as the primary opinions expressed by Dr Parmegiani and Dr Brown. His Honour concluded: "On the medical evidence before me I consider that it is probable that had debriefing and counselling occurred after the shooting incident at Coolabah in accordance with protocol, the risk of the Plaintiff developing PTSD would have been minimised. I prefer the view of Dr Wright, and consider that the delay that occurred in the plaintiff accessing appropriate psychological and psychiatric treatment probably contributed to the development and persistence of the plaintiff's PTSD condition." 64 The Appellant challenges this finding to the extent that it suggests, based on Dr Wright's opinions, that PTSD would not have developed had the early interventions identified taken place. This challenge is open to the Appellant, as none of the doctors was called and accordingly this Court is in as good a position as the trial judge to evaluate the written reports. 65 Although Dr Wright adopted terminology consistent with the view that the Respondent may not have developed PTSD had early intervention occurred, it is clear from the opinion of 27 September 2001, that he was not prepared to express an opinion in terms of probabilities that PTSD would not have occurred, or even that the course of his condition would have been directly altered. The only likelihood he expressed was that early assessment and monitoring would have precluded return to operational duties and the "exacerbation of his condition" associated with those continuing duties, including presumably the Nimmitabel operation. Further, his Honour's reference to minimising the risk of the plaintiff developing PTSD was inappropriate, in a circumstance where the risk had in fact eventuated. At its highest, from the Respondent's point of view, the medical evidence supported a finding that the severity and duration could have been reduced. That is the finding which should, in my view, be accepted, on the balance of probabilities. 66 Because the finding is that, on the probabilities, the conduct of the Appellant materially contributed to the Respondent's condition, there is no occasion to consider whether, had causation not been established, the Respondent could have sued for loss of the chance to avoid an adverse result, being a less than 50% chance, a possibility arguably left open by the High Court in Naxakis v Western General Hospital (1999) 197 CLR 269, rejected by the House of Lords in Gregg v Scott [2005] 2 WLR 268, but adopted by this Court in Rufo v Hosking (2004) 61 NSWLR 678. However, the finding that the Appellant contributed to the harm does not lead to the inevitable conclusion that the Appellant is liable for the whole of the damage suffered by the Respondent from the combined effects of the shooting and the inadequate response of the Appellant's senior officers in the aftermath.

Apportionment of loss 67 The Respondent argued that once it was established, as a matter of probability, that the failure of the Appellant to provide early psychological intervention materially contributed to his psychiatric condition, he was entitled to recover damages from the Appellant for the full extent of that condition, unless the Appellant was able to demonstrate, with a reasonable degree of precision, the extent to which his condition was the result of a pre-existing factor, for which the Appellant was not responsible, namely the firing of shots at him. This conclusion, it was argued, followed from the application of principles identified in Watts v Rake (1960) 108 CLR 158 at 160 (Dixon CJ) and Purkess v Crittenden (1965) 114 CLR 164 at 168. 68 The Appellant adopted a categorically different position. The Appellant argued that, on a fair reading of the evidence, what the Respondent had lost was an opportunity which may have reduced the severity and duration of his condition. There was, the argument continued, no support in the evidence for the proposition that the failure of the Appellant to provide early psychological intervention had caused the condition or indeed necessarily contributed to it in any particular degree. And whilst it was true that the evidence provided little assistance in identifying the likely extent of the exacerbation, or the degree of likelihood that there had been exacerbation, the Court was nevertheless required, in accordance with the principles established in Malec v J.C. Hutton Pty Ltd (1990) 169 CLR 638, to assess the extent of the loss, on the hypothetical basis that early intervention had occurred. 69 There may be a difficulty in reconciling the application of the principles stated in Watts and Purkess and those in Malec, as explained by this Court in Seltsam Pty Ltd v Ghaleb [2005] NSWCA 208 at [101]-[112] (Ipp JA, Mason P agreeing). The concurrent operation of Watts and Purkess, with Malec, is succinctly stated by Professor Luntz, Assessment of Damages for Personal Injury and Death (4th ed, 2002) at [1.9.14]: "Neither Watts v Rake nor Purkess v Crittenden was referred to in Malec v J C Hutton Pty Ltd . To reconcile these different lines of authority, it is necessary to say that the plaintiff must prove on the balance of probabilities that the defendant's negligence did contribute materially to the present symptoms (this is the legal onus that rests on the plaintiff). Once that is satisfied, there is an evidential onus on the defendant of proving that the alleged pre-existing or subsequent natural condition did exist and that this condition in its natural progression would have produced similar symptoms. If the defendant is unable to satisfy the evidential burden, the court will reduce the plaintiff's damages for contingencies to no greater extent than in the ordinary case. If, however, the defendant shows that there was a real chance that the plaintiff would have developed similar symptoms from a natural condition attaching to the plaintiff, the court will make a greater reduction than normal to reflect this increased chance." 70 The author cites authority for the last proposition, including the judgment of Barwick CJ in Wilson v Peisley (1975) 50 ALJR 207 at 209, an authority also referred to by Callinan J in Rosenberg v Percival (2001) 205 CLR 434, at footnote (212). Thus, in Wilson v Peisley, Barwick CJ noted that no question concerning the operation of Watts or Purkess as to onus of proof arose, the existence of a pre-existing condition and its propensity for harm to the plaintiff having been fully made out: p 209. At 210 his Honour stated: "It is not simply a case of compensating the plaintiff for the injured condition without consideration of the potentiality of the pre-existing situation. In the case such as the present, the claim of the defendant to a just consideration of the likely results of that pre-existing condition, as reducing to its proper proportion the damages he should pay for what he has caused, is an important element in assessment. It was for the judge to decide what were the chances of the respondent's pre-existing condition having brought her psychological harm in the future in the ordinary pursuit of her life and at what level those chances should be evaluated in making an award against the appellant."

In an earlier passage his Honour had remarked: "The trauma of the accident for which the appellant was responsible no doubt made a present reality of that which was ever a real possibility. Thus, whilst the appellant must pay for bringing out that condition, what he must pay must, in my opinion, justly reflect the fact that that condition was not merely latent in the respondent but that events, not of an unusual or unlikely kind, could and might in the ordinary course of life have evoked that condition had not the appellant's negligence intervened. The judge included this possibility in the vicissitudes of life which he was bound to bring into account in connection with the assessment of economic loss." 71 In evaluating the conflicting positions of the parties, it is helpful to identify a number of basic principles. First, although it is sufficient that tortious conduct of a defendant materially contributes to an injury suffered by the plaintiff, there may be other causes and, in assessing loss, there are circumstances where it is appropriate to visit on the defendant liability for a proportion only of the loss suffered. Secondly, contributing causes may occur in a sequence, or have a continuing concurrent operation at the time the injury is suffered. Where they operate sequentially, the defendant may be liable for the whole of the loss suffered, as in the case of the negligent conduct which permitted the escape of a prisoner who then damaged the property of a third party: in Dorset Yacht Co v Home Office [1970] AC 1004, the negligent gaoler was found liable for the whole of the damage caused by the escapee. 72 Thirdly, according to the 'egg-shell' skull principle, the defendant will take the victim as she or he is found, and will bear the full extent of the loss suffered, even if the injury is more severe than would have been the case with a person within the normal range of physical or mental attributes. On the other hand, it may be necessary to make allowance, in diminution of the defendant's liability, for harm which would at some stage have been likely to occur in any event, sometimes expressed as a variation of the egg-shell skull principle, namely the 'crumbling skull' principle. This was explained by Major J in the Canadian Supreme Court in Athey v Leonati [1996] 3 SCR 458 at [35]: "The so-called 'crumbling skull' rule simply recognises that the pre-existing condition was inherent in the plaintiff's 'original position'. The defendant need not put the plaintiff in a position better than his or her original position. The defendant is liable for the injuries caused, even if they are extreme, but need not compensate the plaintiff for any debilitating effects of the pre-existing condition which the plaintiff would have experienced anyway. The defendant is liable for the additional damage but not the pre-existing damage … ."

This is, perhaps, merely a colourful way of expressing the principles established in Australia in Watts , Purkess and Malec . 73 Fourthly, where it is appropriate to apportion loss, that can only be done if the injury is in some sense divisible. In Bonnington Castings Ltd v Wardlaw [1956] AC 613, the medical condition contracted by the worker was caused by exposure to silica dust. The worker was exposed to dust both tortiously and without any breach of duty. There being only one injury, to which the tortious exposure made a not insignificant contribution, causation was established. There was no apportionment, presumably because the injury was treated as indivisible, although as noted by Stuart Smith LJ in Holtby v Brigham & Cowan (Hull) Ltd [2000] 3 All ER 421 at [41], the point was not argued in Bonnington itself. 74 It is possible, in principle, that a single injury will be divisible if an approximate division can be made between different causes. In Hatton v Sutherland, at [41] the English Court of Appeal held (per Hale LJ): "Hence if [the defendant] established that the constellation of symptoms suffered by the claimant stems from a number of different extrinsic causes then in our view a sensible attempt should be made to apportion liability accordingly. There is no reason to distinguish these conditions from the chronological development of industrial diseases or disabilities. The analogy with the polluted stream is closer than the analogy with the single fire."

At [42] the Court continued: "Where the tortfeasor's breach of duty has exacerbated a pre-existing disorder or accelerated the effect of a pre-existing vulnerability, the award of general damages for pain, suffering and loss of amenity will reflect only the exacerbation or acceleration. Further, the quantification of damages for financial losses must take some account of contingencies. In this context, one of those contingencies may well be the chance that the claimant would have succumbed to a stress-related disorder in any event." 75 Fifthly, where a plaintiff proves that tortious conduct materially contributed to his or her injury, an evidentiary onus will lie on the defendant to establish that other causes, including both concurrent causes and pre-existing, but on-going, conditions, also materially contributed. In this case the evidence of a cause for which the Appellant was not responsible was clearly established. Where there is evidence to demonstrate such a contribution, the Court must determine what proportion should be attributed to the wrongful conduct of the defendant and what proportion to other factors for which the defendant is not legally responsible. In Hole v Hocking [1962] SASR 128 Napier CJ had to address the possibility that a serious brain haemorrhage would have occurred absent the accident for which the defendant was responsible. After referring to Smith v Leech Brain & Co Ltd [1962] 2 WLR 148 for the proposition that the defendant, while taking his victim as he finds him, is "responsible for the damages that flow from the wrongful act, but not for consequences that must - or would probably - have ensued in any event", his Honour continued at 133: "In the circumstances as I find them, it seems to me that it would be idle to go through the farce of attempting to calculate what is totally incalculable. I think that the only course open is to allow a round sum which I regard as ample to cover what the plaintiff may have suffered by the haemorrhage having occurred, when it did instead of later, as well as anything that he may have suffered by the haemorrhage being, perhaps, more extensive than it otherwise would." 76 In Purkess v Crittenden at 168, the Court spoke of the burden on the defendant to disentangle the extraneous condition "with some reasonable measure of precision". In relation to psychiatric conditions, precision, in any scientific sense, tends to be an aspiration rather than a reality. In keeping with the principle stated in Watts and Purkess, the evidence relied on by the defendant must demonstrate a substantial likelihood, rather than a speculative chance. As Barwick CJ stated in Purkess: "That being done, it is for the plaintiff upon the whole of the evidence to satisfy the tribunal of fact of the extent of the injury caused by the defendant's negligence." 77 The real issues are when apportionment is deemed appropriate and how it is achieved. As noted by Professor Luntz, Assessment of Damages for Personal Injury and Death (4th ed, 2002) at [1.9.11] the relevant principle was concisely stated in Savini v Australian Terrazzo & Concrete Co Pty Ltd [1959] VR 811 (Full Court). At 821, Sholl J identified the relevant context as that where - "the loss is ultimately shown to be distributable between two actual causes - first, the defendant's tortious conduct, and, secondly, an act of God or other event for which the defendant is not responsible. Damage flowing from two sources has joined, so to speak, to form one stream, but if it is found still to be possible to measure the respective volumes of the components the law will take notice of the measurement and treat them as distinct. Otherwise, it will not; for it does not lie in the mouth of the defendant to say that, although he originated one stream of damage, its inseverable admixture with another means that none can be traced back to him." 78 The principle of apportionment in such a case is not novel: in Middleton v Melbourne Tramway and Omnibus Co Ltd (1913) 16 CLR 572, a boy was injured when knocked down by a tram and dragged under its wheels. The initial collision occurred without negligence on the part of the tram driver, when the boy ran from behind another tram into the path of the tram which ran him down. The question of negligence was limited to the speed with which the driver applied the brakes and stopped the tram. At 590, Isaacs J stated: "Learned counsel for respondents raised a question as to the damages. He said that as the injuries to the appellant may have resulted, in part at all events, from those acts of the respondents which preceded the 19 feet of excess, the appellant was bound to give some evidence to discriminate between those injuries and the injuries resulting from the negligent 19 feet. It is true that the respondents are not to be held responsible except for their actionable negligence … . But, where the evidence for the plaintiff, if believed, is sufficient not only to establish liability, but also to enable a jury with reasonable certainty, if they so conclude, to attribute to the defendant's wrongful conduct as an effective and proximate cause the injuries complained of, the plaintiff has so far discharged his burden of proof; otherwise he might be left without redress against an admitted wrongdoer. The onus then is on the defendant - unless he can succeed in satisfying the jury upon the plaintiff's evidence - to negative the inference of his total responsibility, or to distribute the damage arising by showing, if he can, that the damage accrued or must in any case have accrued, wholly or partly from some other cause."

Barton ACJ adopted a similar approach at 580-581; Rich J agreed at 591. Although the case arose at a time when contributory negligence was a complete defence and there was a tendency to uncouple stages in the causes of an accident, there is no reason to suppose that the approach upheld by the High Court is at odds with modern law requiring apportionment for injury arising from separate causes. Thus where an injury is divisible, and part only flows from the negligence of the defendant, liability is limited to that part which can be so identified. But, consistently with Purkess , the onus falling on the defendant, referred to by Isaacs, must be understood as an evidentiary onus. 79 In Dillingham Constructions Pty Ltd v Steel Mains Pty Ltd (1975) 132 CLR 323 the High Court considered the contribution between tortfeasors in relation to sequential injuries, for the purposes of s 5(1)(c) of the Law Reform (Miscellaneous Provisions) Act 1946 (NSW). In 1968, a workman had suffered an injury which rendered him susceptible to further injury, as the result of the negligence of his then employer, Dillingham. In 1970, he suffered a second injury whilst in the employ of his new employer, Steel Mains. Steel Mains sought contribution from Dillinghams, on the basis that it had contributed to the second injury. The High Court unanimously rejected the argument that contribution would be available in such circumstances. Barwick CJ (with whom Gibbs, Stephen and Mason JJ agreed), noted that the there were two injuries, two unrelated acts of negligence and two separate and distinct torts. His Honour continued (at 326): "The injury suffered through the later tort may have exacerbated a condition initially induced by the prior tort. … If such a possibility or probability of further deterioration became a reality by virtue of the subsequent tort, the amount of compensation payable for that subsequent injury may be lessened because of the deteriorated condition of the worker already present at the time of the receipt of the further injury. But it would rest upon the subsequent tortfeasor to establish the pre-existing condition for which he was not responsible - see Watts v Rake and Purkess v Crittendon . … The subsequent tortfeasor is not in any sense liable for the injury which the first tortfeasor caused or for its consequences, though if he is unable in point of proof to establish the pre-existing disability of the injured person the damages he may be required to pay will not be diminished by reason of the pre-existing condition of the injured person."

In further reasons at p 329, Gibbs J stated: "If, then, the cross-claimant by his tort caused the plaintiff to suffer a similar injury and this aggravated the plaintiff's condition, the damages payable by the cross-claimant would be measured by the extent to which the plaintiff's condition had been rendered worse by the second injury." 80 Where the injury arises from the constitution of the plaintiff, Watts, Purkess and Malec require that allowance must be made for the disability which may in due course have led to incapacity absent the tortious conduct of the defendant. Malec concerned damage which it was established on the probabilities would have occurred in any event. In the present case it is likely that the Respondent would have suffered a level of PTSD causing him loss in any event, from being shot at. There is, of course, a difference between the circumstance where a loss created by the defendant might have occurred in any event, and the present case, where an event which had occurred, absent the Appellant's breach of duty, gives rise to a loss which was materially increased because of the subsequent breach of duty by the Appellant. Nevertheless, it follows from Middleton and Dillingham that there is no reason to adopt in the latter case an approach which would not be adopted in the former, and ascribe the whole of the loss to the defendant. In my view, the trial judge should have apportioned the harm done as between the shooting and the conduct of senior police officers in its aftermath, as best he could on the medical and psychological evidence. He did not do this, with the result that his Honour's assessment of loss must be set aside. This Court having received no submissions as to an appropriate apportionment, it will be necessary to remit the matter for this aspect of the trial to be completed. Contributory negligence 81 The fourth challenge made by the State to the decision of the trial judge was directed to the assessment of contributory negligence. The trial judge assessed contributory negligence at 10%, on the basis that the Respondent had failed to report symptoms of stress or to seek counselling prior to May 1999. The trial judge took into account the fact that the Respondent "was a peer support officer himself, and was aware that everything was 'not quite right' so far as his psyche was concerned". On the other hand, his Honour took into account the discouragement from seeking psychological assistance which he accepted that the Respondent had deduced from the comments of Inspector Ruming. 82 The basis on which the State sought to challenge that assessment was that the consequence of its arguments in relation to the proportionate reduction of the damages for which it was responsible must have an "obverse" effect in relation to contributory negligence. However, it does not follow that because part of the loss suffered is not the responsibility of the defendant that it is the liability of a plaintiff. In the case of a pre-existing natural condition, no person will have responsibility for part of the loss, and that part will not be the subject of compensation. In this case, there may have been a separate liability on the part of the person who fired the shots, but no action was taken in relation to him. 83 Otherwise the complaint is no more than that the trial judge failed to give proper weight to what was said to be a conscious determination of the Respondent to "tough it out" in the quantum of the reduction. There are three reasons why this challenge should not be accepted. First, there are generally difficulties in placing weight on the responsibility of the victim for self-diagnosis, in a case involving psychological or psychiatric injury. Secondly, the force of the challenge is diminished by his Honour's finding in relation to the discouragement given by Inspector Ruming, when the Respondent expressed his state of distress to him. Thirdly, such an assessment is inevitably an evaluative judgment and, the trial judge having the advantage of seeing the Respondent in the witness box, it is on any view difficult for an appellate court to intervene. There is no reason for intervention demonstrated in the present case.

Costs 84 The Appellant has had some success in relation to the issues raised on the appeal, though it has been unsuccessful in other respects. I would propose that the Respondent pay 25% of the Appellant's costs of the appeal. He is entitled to a certificate under the Suitors' Fund Act 1951 (NSW) in respect of the costs of this appeal. 85 It appears that an offer of settlement was made in the proceedings in the District Court, which resulted in a particular costs order in that Court. We were told that the offer was not renewed in this Court, but were invited to reserve any question of costs pending further submissions. The parties should have the opportunity to provide an agreed form of order as to costs, or, if no agreement can be reached, submissions in writing in relation to the question of costs within 14 days.

Proposed orders 86 I would propose the following orders:

(1) Appeal allowed in part and orders 1 and 2 made by the District Court on 22 October 2004 be set aside.

(2) Remit the matter to the District Court for assessment of damages with respect to the loss suffered by the Respondent as a result of the negligence of the Appellant, in accordance with the principles identified by this Court.

(3) The Respondent pay the Appellant 25% of its costs of the appeal.

(4) The costs of the trial should abide the outcome of the further trial with respect to the assessment of damages.

(5) The Respondent shall have a certificate under the Suitors' Fund Act 1951 (NSW) in relation to the costs of the appeal. 87 HUNT AJA: I agree with the orders proposed by Basten JA, except order 2. I agree with the order 2 as proposed by the Chief Justice. I agree generally with the reasons given by the Chief Justice, but there is one issue on which I wish to state my own reasons. 88 It appears these days to be almost commonplace for the medical issues in personal injury cases in the District Court to proceed on the basis of reports without calling the doctors who wrote those reports as witnesses in the case, notwithstanding the frequent dispute between the doctors whose reports are tendered by the plaintiff and the doctors whose reports are tendered by the defendant. As such medical reports rarely deal with the views expressed in the other reports, the judge is left with the difficult task of determining which reports to accept without the very real assistance which can often be given by a medical witness when different facts as to what happened, and different views as to the consequences of what happened, are put to the doctor in cross-examination. 89 This situation becomes even more difficult for the judge when the doctors express their reports in what may have been intended to be legal terminology. Some doctors have a good understanding of those terms; some do not. If the doctor is not called as a witness, it is, in my view, unsafe to rely on the doctor's adoption of legal terminology unless it is reasonably clear from the report itself that the doctor does indeed understand the legal meaning of those terms. The legal meaning is sometimes quite different from the medical meaning. 90 In the present case, Dr Wright (whose views were critical on the issue of causation) has used the terms "caused" and "contributed" with reference to the condition of post-traumatic stress disorder from which the respondent suffered. The first was to the respondent's condition having been "caused" by the shooting incident, and the second was to the appellant's omissions in relation to the treatment for that condition having "further contributed to the development and persistence" of that condition. Dr Wright appears to have used the word "contributed" in the same sense as "exacerbated", which is how he has more often described the consequences of the appellant's omissions. However, it is by no means clear (at least to me) that Dr Wright has used them in the legal rather than the medical sense. 91 Dr Wright was not called as a witness, no doubt because the appellant did not request his attendance for cross-examination. But, as the respondent had the onus of proving his case on causation, if there is any problem with his doctor's report on that issue, it is the plaintiff who must suffer in relation to the proof of his case. The Chief Justice has found (in pars [14] and [23]) that the distinction drawn by Dr Wright between cause and contribution/exacerbation should be interpreted as reducing the extent of the contribution made to the respondent's condition of post-traumatic stress disorder by the appellant's omissions to something necessarily less than a material contribution. This issue does not appear to have been investigated at the trial at all. The word "exacerbation" is generally used by the medical profession as meaning only that the original condition is made worse (or more serious), usually involving a greater intensity in the symptoms of that condition. That increase in severity may be minor, medium or extreme. The word exacerbation does not mean to me that the act which led to the exacerbation was necessarily something less than a material contribution to the condition exacerbated. 92 I nevertheless agree with the Chief Justice that it was not open to the trial judge in the present case to find on the evidence as it was left that the appellant's omissions materially contributed to (and thus was a cause of) the condition from which he now suffers. That is because Dr Wright was never asked to explain what he meant by his use of these phrases, and the respondent must suffer the consequences of the failure to have Dr Wright identify the extent to which those omissions exacerbated the original condition. 93 However, that does not mean that, when the District Court has to decide the issue now remitted to it, an assessment of "the loss of the chance of a better medical outcome", it will not be open to the respondent to argue that the extent of the loss of the chance in this particular case was a substantial one. **********

15/02/2006 - Typographical errors - Paragraph(s) [74], [75]

DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated.