City of Stirling v Tremeer
[2006] WASCA 73
•10 MAY 2006
CITY OF STIRLING -v- TREMEER [2006] WASCA 73
| (2006) 32 WAR 155 | |||
| SUPREME COURT OF WESTERN AUSTRALIA | Citation No: | [2006] WASCA 73 | |
| THE COURT OF APPEAL (WA) | |||
| Case No: | FUL:42/2004 | 19 & 20 JANUARY 2006 | |
| Coram: | STEYTLER P ROBERTS-SMITH JA MCLURE JA | 10/05/06 | |
| 35 | Judgment Part: | 1 of 1 | |
| Result: | Appeal allowed | ||
| A | |||
| PDF Version |
| Parties: | CITY OF STIRLING GAVIN JOHN TREMEER |
Catchwords: | Tort Negligence Fall by adult from children's playground equipment Whether failure to provide a soft surface caused the injury the subject of the claim. |
Legislation: | Nil |
Case References: | Bennett v Minister for Community Welfare (1992) 176 CLR 408 Bonnington Castings Ltd v Wardlaw [1956] AC 613 Chappel v Hart (1998) 195 CLR 232 Fairchild v Glenhaven Funeral Services Ltd [2003] 1 AC 32 Fox v Percy (2003) 214 CLR 118 Henville v Walker (2001) 206 CLR 459 I & L Securities Pty Ltd v HTW Valuers (Brisbane) Pty Ltd (2002) 210 CLR 109 McGhee v National Coal Board [1973] 1 WLR 1 Naxakis v Western General Hospital (1999) 197 CLR 269 Nicholson v Atlas Steel Foundry & Engineering Co Ltd (1957) 1 WLR 613 Purkess v Crittenden (1965) 114 CLR 164 Rosenberg v Percival (2001) 205 CLR 434 The State of Western Australia v Watson [1990] WAR 248 Thompson v Smiths Shiprepairers (North Shields) Ltd [1984] QB 405 Abalos v Australian Postal Commission (1990) 171 CLR 167 Fitzgerald v Penn (1954) 91 CLR 268 March v E & M H Stramare Pty Ltd (1991) 171 CLR 506 Medlin v State Government Insurance Commission (1995) 182 CLR 1 Romeo v Conservation Commission of the Northern Territory (1998) 192 CLR 431 Waterways Authority v Fitzgibbon (2005) 79 ALJR 1816 |
JURISDICTION : SUPREME COURT OF WESTERN AUSTRALIA TITLE OF COURT : THE COURT OF APPEAL (WA) CITATION : CITY OF STIRLING -v- TREMEER [2006] WASCA 73 CORAM : STEYTLER P
- ROBERTS-SMITH JA
MCLURE JA
- Appellant
AND
GAVIN JOHN TREMEER
Respondent
ON APPEAL FROM:
Jurisdiction : DISTRICT COURT OF WESTERN AUSTRALIA
Coram : KENNEDY CJDC
Citation : TREMEER - v - CITY OF STIRLING [2004] WADC 56
File No : CIV 3402 of 1993
(Page 2)
Catchwords:
Tort - Negligence - Fall by adult from children's playground equipment - Whether failure to provide a soft surface caused the injury the subject of the claim.
Legislation:
Nil
Result:
Appeal allowed
Category: A
Representation:
Counsel:
Appellant : Mr J Gilmour QC & Mr D McKenna
Respondent : Mr K J Bradford
Solicitors:
Appellant : Jarman McKenna
Respondent : Bradford & Co
Case(s) referred to in judgment(s):
Bennett v Minister for Community Welfare (1992) 176 CLR 408
Bonnington Castings Ltd v Wardlaw [1956] AC 613
Chappel v Hart (1998) 195 CLR 232
Fairchild v Glenhaven Funeral Services Ltd [2003] 1 AC 32
Fox v Percy (2003) 214 CLR 118
Henville v Walker (2001) 206 CLR 459
I & L Securities Pty Ltd v HTW Valuers (Brisbane) Pty Ltd (2002) 210 CLR 109
McGhee v National Coal Board [1973] 1 WLR 1
Naxakis v Western General Hospital (1999) 197 CLR 269
Nicholson v Atlas Steel Foundry & Engineering Co Ltd (1957) 1 WLR 613
(Page 3)
Purkess v Crittenden (1965) 114 CLR 164
Rosenberg v Percival (2001) 205 CLR 434
The State of Western Australia v Watson [1990] WAR 248
Thompson v Smiths Shiprepairers (North Shields) Ltd [1984] QB 405
Case(s) also cited:
Abalos v Australian Postal Commission (1990) 171 CLR 167
Fitzgerald v Penn (1954) 91 CLR 268
March v E & M H Stramare Pty Ltd (1991) 171 CLR 506
Medlin v State Government Insurance Commission (1995) 182 CLR 1
Romeo v Conservation Commission of the Northern Territory (1998) 192 CLR 431
Waterways Authority v Fitzgibbon (2005) 79 ALJR 1816
(Page 4)
1 STEYTLER P: I agree with McLure JA.
2 ROBERTS-SMITH JA: I have read the draft reasons prepared by McLure JA. I agree with her Honour's reasons and have nothing to add.
3 MCLURE JA: The respondent is a quadriplegic as a result of falling from a track ride in a children's playground in a public park in the municipality controlled by the appellant, the City of Stirling (referred to below as the appellant or the City). The accident occurred on 22 September 1989 at which time the respondent was aged 23 and was six foot one inch (1854 mm) tall.
4 The City appeals from the finding of Kennedy CJDC that the respondent's injuries occasioned by the fall were caused by the City's negligence in failing to have sufficient soft sand underneath the playground equipment from which the respondent fell. At the time of the accident there was patchy grass at the sides of the track ride and yellow sand in a shallow depression immediately underneath it.
5 The City conceded in the appeal that it owed a duty to persons entering the park, including the respondent, to take reasonable care to avoid foreseeable risk of injury to such persons who might use the children's playground equipment and that the response of a reasonable person in the City's position to the risk of injury, relevantly, was to provide in the order of 300 mm of soft sand beneath such equipment. The City identified the issues in the appeal as follows:
(a) was the City's negligence in failing to provide in the order of 300 mm of sand the cause of, or did it materially contribute to, the respondent's injuries as a result of him falling from the track ride;
(b) were the respondent's injuries caused solely by his own negligence in positioning himself essentially upside down prior to the fall; and
(c) if the City's negligence did materially contribute to the respondent's injuries, was the respondent guilty of contributory negligence and, if so, to what degree, in positioning himself essentially upside down prior to the fall.
(Page 5)
Background
6 The track ride was part of an integrated collection of playground equipment that had been constructed on behalf of the City in Bardon Park, Maylands around two months before the accident. In addition to the track ride, the playground equipment included slides at both ends, hook climbers, a suspension bridge, a log roll and step decks.
7 The track ride comprised a horizontal overhead track that was clamped to four upright posts, two at each end. The top of the overhead track was 2.5 metres above the ground and the underside of the track was around 2.4 metres above the ground. A triangular-shaped handle was suspended by a chain from a 4-wheel carriage which was housed within and travelled along the length of the overhead track which was 3 metres. At each end of the track was a platform which was slightly raised off the ground. The distance between the closest edges of the two platforms was 3.83 metres. The user was expected to, whilst standing on the platform at one end, put his or her hands through the handle to grasp it and push himself or herself off the platform to travel, whilst suspended from the handle, to the platform at the opposite end. As the track was horizontal, there was no gravitational pull, unlike a flying fox. The triangle was 150 mm at the base and 110 mm at both sides. It could accommodate two hands side by side of children up to 12 years. Adult hands could only be accommodated if they overlapped at the base of the triangle. The handle could rotate about its vertical axis by about one and a half turns. At the time of the accident, the base of the handle was approximately 2 m (1.765 m plus 9 inches) above the ground.
8 There was a conflict of evidence at trial as to how the accident occurred. According to the respondent he was standing on the platform and grabbed the handle with both hands with his palms facing towards him. He pushed off the platform with his legs, pulled his legs up so that his knees were near his chest and about halfway across he felt a jerk, his hands slipped off the handle and he flipped backwards in what he described as a somersault with his head hitting the ground first. The City's case theory was that the respondent had positioned himself essentially upside down prior to the fall. The trial Judge accepted the respondent's account of what occurred. I propose to start with the mechanism (cause) of the injuries because that is also relevant to whether the City's negligence caused the loss and damage.
The mechanism of the injury
9 The relevant grounds of appeal (2, 3, and 4) are as follows:
(Page 6)
- "2. The learned trial Judge erred in finding that, in effect, just before the respondent fell from the trak ride, his knees were near his chest (in a ball position) and his legs from his knees to his feet were out more or less straight.
3. This finding was against the totality of the evidence on the balance of probabilities [particulars supplied] …
4. The learned trial Judge should have found, upon the totality of the evidence … that the respondent was in an upside down, or near upside down position when he lost his grip of the handle of the trak ride, this being the only reasonable inference open on that evidence."
10 The trial Judge found that the accident happened in the way in which the respondent and his sister-in-law, Margaret Tremeer, described. The trial Judge said (at [67] - [68]):
"The [appellant] had pulled himself up onto the handle. Because the chain was very short, he was able to pull himself up very high. Because he had a lot more strength than a child would have, he was able to do that so that he was in a ball position, but his legs were out. Plainly he was moving and may have been rocking, as his hand slipped he somersaulted and landed directly onto his head. He was not crouched upside down with his legs above his head either pointing toward or around the central bar of the track ride, nor was his head pointing to the ground immediately before the accident. He had pulled himself up, what might be regarded as too high, because he had the strength to do that and because the handle and chain were simply too small for him so that when he pulled himself up eventually his hands slipped and he flipped over.
…
It is not the case that his body was in a completely upright position. It simply was not upside down. He was not hanging from the track ride or on top of the track ride and his legs were not higher than his head."
11 She continued (at [80] and [89]):
… The [appellant] has never said that he was in an upright position and then suddenly fell on his head. He has always said
(Page 7)
- that his knees were pulled up but with his head higher than his body and when his hands slipped, he somersaulted over and landed on his head. It is likely that as he kept using the track ride he pulled himself up further so he was finely balanced and could have fallen either way.
…
[T]he [appellant's] injury was directly to the top of his head … The injury in the circumstances is consistent with the fact that in the moment before his hand slipped he was crouched in a cradle-like position moving forward, his hands slipped, he suddenly flipped into a somersault and hit his head … "
12 The trial Judge's description of the respondent's position just prior to the fall (his body was not upright and he was finely balanced for a fall) is her interpretation of the evidence. The respondent's evidence was that he grabbed the triangle, pushed off the platform with his legs, brought his legs up towards his chest and felt a great jerk, his hands slipped and he somersaulted backwards and landed on the top or crown of his head. The respondent said he was upside down after he lost his grip. He denied that he was pushed or that he swung his legs up over his head. He was cross-examined about the position of his body before the fall as follows:
"At the time that your hands slipped is it your evidence that your head and your body were vertical to the ground?---Vertical
Do you know what I mean by vertical? Straight up and down. If that is the ground, were you hanging straight up and down with your head at the top when you fell?---When you mean I was hanging - you mean, like I said
So your head was at the top?---At the top, yes.
And then your body with your legs pulled into your chest?---Yes.
That's what you say happened?---Yes, that's what happened.
In that position how far do you say that your bottom was from the ground?---My bottom, halfway.
How high above the ground, about a metre?---Yes, probably; halfway from the actually flying fox.
(Page 8)
- Halfway up the flying fox, that's about a metre?---A metre, yes.
And you say that there was a jerk?---Yes.
And that you moved from being in that vertical position to going through 180 degrees backwards?---A somersault backwards."
13 The trial Judge had concerns about the respondent's comprehension of questions. Certainly, it is unclear from the above exchange whether the respondent intended to agree with the propositions that his body was vertical to the ground and that he rotated 180 degrees.
14 The trial Judge did not make any finding as to the specific injuries suffered by the respondent in the fall but they were not in dispute. They are relevant when considering the mechanism of the accident. The injuries include a fracture through the right C3 articular pillar; lateral subluxation of the right C3/4 facet joint; fractures involving the right lateral mass of the C4 vertebrae including the right C4 pedicle and the articular pillar and fracture of the C4 lamina; forward displacement of the C4 on C5 vertebra; unilateral dislocation and disruption of the right C4/5 and right C5/6 facet joints; a comminuted burst fracture of the C5 vertebrae with retropulsed fragments displaced posteriorly resulting in marked narrowing of the spinal canal; fracture of the left C5 lamina at its junction with the spinous process; lateral subluxation of the left C5/6 facet joint; an oblique sagittal fracture through the body of the C6 vertebrae; and fracture of the left C6 lamina.
15 The appellant contends that the preponderance of the independent objective evidence supports the conclusion that the respondent was head down before he fell, relying in particular on the evidence of three medical doctors (Dr S Dunjey, Mr P Hardcastle and Mr N Batalin), a biomechanical engineer called by the City (Mr E Scull) and the respondent's sister-in-law, Margaret Tremeer.
16 On the date of the accident, Dr Dunjey had a discussion with the respondent in the resuscitation room of the emergency department at Royal Perth Hospital ("RPH"). He said he could not recall the respondent's specific responses to his questions. He was then asked:
"Do you remember, if I can put it this way, the substance of what you put to him and the substance of his response?---I think the questions were along the lines of, 'Are you in pain, how did this happen?' And my recollection of the responses is that he
(Page 9)
- was hanging upside down from some children's playground equipment and slipped and fell and landed on his head and hyperflexed his neck. He wouldn't have put it in those words but his head was twisted and as a result he had an instantaneous loss of sensation and movement."
17 Dr Dunjey did not make a note of the respondent's response. Further, he was first asked to give a statement about his contact with the respondent three or four months before trial. The accident occurred some 14 years before trial.
18 The following exchange occurred in cross-examination:
" … I just want to ask you about your evidence you have given up to now. I think you have told us that you never made any notes?---Mm.
And the triage nurse made some notes and you remember with the precision that you have just given evidence that he was hanging upside down?
Gilmour, Mr: Your Honour, the witness has just nodded.
Kennedy DCJ: Sorry you can't nod---Yes. I do, I'm sorry. Yes, that’s correct.
Yes.
Bradford, Mr: From some playground equipment---Yes.
You didn't know what it was, and he slipped and he fell?---Yes.
Slipped from where?---My understanding at that time was that he had his knees hooked over something, perhaps supporting himself with his hands and his grip slipped and he fell.
Is that something you remember or is it your impression that you got from talking to him?---Because I can't actually recall the absolute specifics, I would be prepared to concede that it may have been the impression I go[t].
Yes?---Because I can't recall his exact words at the time that it happened."
(Page 10)
19 He was then asked about impressions fading with the years and he said that his recollection was patchy but continued:
"There are several things that I was left with a fairly strong feeling about even 14 years down the line and one of them was that he was hanging upside down."
20 After accurately summarising Dr Dunjey's evidence, the trial Judge said that she did not accept that Dr Dunjey's "impression is correct".
21 The appellant contends that the witness's reference to impression, properly understood, is a reference to the witness's understanding of the substance of what he was told by the respondent, he being unable to recall the exact words. I do not read her Honour's reasons to suggest anything to the contrary. It is apparent from her reasons on this subject as a whole, that the trial Judge did not regard the evidence as reliable because, after the initial review, the respondent was not Dr Dunjey's patient, he made no case note or other record of the conversation and was first asked to recall matters some 14 years later. It was clearly open to the trial Judge to regard Dr Dunjey's evidence as unreliable.
22 Mr Hardcastle was a consultant orthopaedic surgeon at RPH who performed a halo procedure on the respondent shortly after the accident. Mr Hardcastle saw the respondent on 25 September 1989 at RPH in the course of a ward round. It was his practice to dictate notes shortly after the completion of the round. He dictated a note in the following terms:
"This lad was involved in an accident on 22/9/89. He had been drinking about 3 cans of beer and was on a flying fox at Maylands, crouched upside down when for some reason he fell. He is uncertain of the reason for this as are any observers."
23 Mr Hardcastle was not challenged on this evidence. The appellant also relies on Mr Hardcastle's medical assessment. Mr Hardcastle noted in a report tendered in evidence that the radiological findings demonstrated a very severe comminuted burst fracture with a sagittal split and that the forces appeared to be those of axial compression, some flexion and a lateral deviation. A comminuted burst is one where multiple pieces of bone are splayed apart. According to Mr Hardcastle, the major force was axial compression, vertically through the spine. The flexion force was a consequence of the head being forced forward towards the chest and the lateral movement was a sideways movement of the neck causing more compression on one side. He said the findings were
(Page 11)
- consistent with a fall directly onto the skull in a position directly perpendicular to the ground followed by a lateral deviation of the head.
24 Mr Batalin was also a specialist orthopaedic surgeon. He had very extensive experience in treating spinal injuries. He was called by the City. In a report tendered in evidence, Mr Batalin described the respondent's injuries as very significant. He continued:
"Although from the available documentation it is difficult to elicit the exact mechanism of injury, I would have suspected (taking into consideration the patient's level of disability and his Xrays) the injury occurred with the patient initially being in some degree of 'upside-down' position. The sort of injury that was sustained by Mr Tremeer suggests to me either a somersault whilst travelling at high speed, (eg being pushed by somebody) or travelling at speed on a flying fox in an upside-down position.
Taking into consideration the available photographs of the equipment and the intended use of the equipment one would postulate that if a fall occurred as a result of loss of hand grip with the individual using the equipment in the normal intended manner, he would have most likely fallen on his feet … I believe that the injury, more likely than not, would have occurred with the head striking the ground at very considerable force. I would have felt that factors such as considerable acceleration at the time of using the flying fox (eg being pushed by somebody) and/or being in an extraordinarily unnatural position whilst using the equipment has to be excluded."
25 Mr Batalin's evidence was that the nature and extent of the respondent's injuries meant that the respondent must have fallen onto his head with very significant force. He sees most surfing spinal injuries in this State and did not recall seeing "such anatomical severity of so many fractures involved".
26 The respondent's account of how the accident occurred was put to Mr Batalin in cross-examination as follows:
"What I want to put to you is if someone with their hands towards themselves, like that, jumps on to the flying fox, right, there is a forward momentum and as they are doing that they bring their knees up to the chest, lose control of the flying fox. They then go into a somersault position directly on to the head
(Page 12)
- at the wrong moment. That is consistent with this injury?---Yes, I would've anticipated more forces. There's considerably more force to my mind to produce that injury."
27 In re-examination, counsel for the City put what he understood to be the respondent's evidence of how the accident occurred as follows:
" … [The respondent] said that just before he fell his head and his body were vertical to the ground, with his head at the top. That is the first thing. He said that the distance from his bottom to the ground was about a metre and that his knees were tucked up towards his chest and that after he fell, after he lost his grip from a vertical position with his head at the top and his knees up he says that he fell through 180 degrees and landed on his head. Do you follow that description?---I follow the description.
He had 1 metre to fall?---Yes. I'm waiting for your question.
What do you say about that in terms of the injury that he suffered?---Its highly improbable to produce the injury that we see in the end analysis. See, there's incontrovertible evidence what the damage is. We see that now. We have x-rayed it. I find it very difficult and improbable for the mechanism you've just described to produce that sort of injury."
28 It is apparent from the questions that her Honour's findings as to how the respondent came to fall on his head were not put by either party to Mr Batalin.
29 Mr Scull agreed that there was a severe impulse delivered to the respondent's skull in an approximately superior-inferior direction, being a force applied from the top of the head along the axis of the spine, producing a severe axial compression force. He calculated that the time taken for the respondent to fall 970 mm to the ground was less than half a second which the appellant contended was, by inference, insufficient for the respondent to somersault through approximately 180 degrees. As the trial Judge observed (at [153] and [166]), on her findings as to how the accident occurred the respondent would have fallen further than Mr Scull estimated under the effect of the momentum generated by the partial somersault.
30 Margaret Tremeer's evidence in chief was that she saw the respondent leave the platform and pull his legs up with his knees to his
(Page 13)
- chest. However she looked away to speak to another person and did not see the respondent fall.
31 Ms Tremeer had signed a statement that was tendered in evidence (exhibit 20). A supplementary statement was prepared for her but was not signed (exhibit 21). The unsigned statement was to the effect, inter alia, that the respondent did not take a run to get the flying fox moving but he just held onto the handle with both hands and pulled himself up into a "jack-knife position" with both feet up towards the rail of the flying fox. She was cross-examined about that matter as follows:
"Did Gavin just hold on to the handle of the flying fox with both hands and pull himself up?---He pushed off and then pulled his legs up.
Did he pull himself up into a jack-knife position?---Do you mean legs out in front or up towards his chest?
What I mean by - yes - that is this: did he pull himself up into a jackknife position with both feet up towards the rail of the flying fox or track ride?---Yes. Yes.
So did he have one leg either side of the overhead rail of the track ride?---No. No, out in front.
But both of his feet were pointing towards the rail of the track ride, weren't they?---It's hard to say. It was more towards his chest and down a bit, rather than up high.
…
He had his feet pointing and legs, his legs were roughly straight, were they?---Sort of, like, he had his knees sort of near his chest and, like, his legs sort of out, his feet sort of out.
I see?---I can't do it, you know, like he had his knees sort of up and his legs sort of out a bit in front of him, say, so not like straight out in front of him because he's pretty tall. It was more up and out.
Did he have his knees towards his chest?---Yes.
And the part of his legs from his knees to his feet pointing in front of him?---Yes. Well I wouldn't have - yes. Yes, sort of like that."
(Page 14)
32 It is clear from this exchange that the witness did not understand the jack-knife position to involve the respondent's legs being higher than his head or pointing towards the rail. She said his knees were on his chest and his legs from his knees to his feet were more or less straight out.
33 The respondent's evidence and that of his sister-in-law was inconsistent with the appellant's case theory that the respondent was in an upside down, or near upside down, position before he lost his grip off the handle of the track ride. Dr Dunjey's evidence was of questionable reliability for the reasons given by the trial Judge. As to the expert evidence, the appellant contended first, that based on the nature and extent of the injuries, the primary force on the respondent's head and spine was axial compression resulting from him falling in an upside down position onto his head and second, that the trial Judge's finding is inconsistent with the expert evidence. The first contention is, on my understanding of the expert evidence, correct. However, I am not persuaded of the correctness of the second. The trial Judge found that the respondent fell further than 970 mm directly onto the top of his head. Her findings are consistent with the respondent falling a height of more than 970 mm in an upside down position head first onto the ground under momentum generated by a partial somersault. That being so, her findings are consistent with the expert evidence. Furthermore, her findings are based in part on her credibility assessment of the respondent and Ms Tremeer. Accordingly, the appellant is required to establish that the findings are glaringly improbable or contrary to compelling inferences: Fox v Percy (2003) 214 CLR 118. It has failed to do so. I am satisfied that the trial Judge's findings were reasonably open on the evidence. The question of contributory negligence also falls away because the appellant cast this ground as dependent on a finding that the respondent had positioned himself essentially upside down prior to the fall. I would dismiss grounds 2, 3 and 4 .
Whether negligence caused the injuries
34 Both parties adduced expert evidence on causation. The respondent called two experts, Mr J Lane from Soil & Rock Engineering Pty Ltd and Mr A van der Meer of van der Meer & Associates. The City tendered two reports prepared by ETRS Pty Ltd ("ETRS") dated 24 January 1996 (exhibit 52) and 27 March 1996 (exhibit 53) respectively. The reports were tendered by consent and the authors were not required to attend for cross-examination. The City called Mr E Scull, a biomechanical engineer. Grounds 7 and 8 deal with causation. They are in the following terms:
(Page 15)
- "7. The learned trial Judge erred in law and fact in finding that had there been a foot or more of loose beach sand then the respondent probably would not have suffered 'this injury' (presumably meaning quadriplegia), in that:
(a) There was no evidence directly or indirectly capable of supporting such a finding as her Honour tacitly acknowledged.
(b) There was no evidence that the sand used in the tests conducted by ETRS reports of which were admitted into evidence by consent was not loose beach sand or its equivalent. The evidence as the learned trial Judge correctly noted, was that the sand used was dry, not compacted in any way and was screed flat before each test. Furthermore, the soft sand used by Soil & Rock Engineering Pty Ltd for the comparative tests was 'loose white fine to coarse grain sand with some shells' and was in all probability beach sand.
(c) All of the evidence going to the issue of differential injuries associated with different surfaces was to the effect that, even if the surface below the trak ride was soft sand it was highly or quite likely that the respondent would have suffered the same injuries [particulars supplied].
8. The learned trial Judge should have found that the respondent failed to establish that he would not have suffered his injuries if there had been soft sand (of any depth) beneath the trak ride and accordingly failed to establish that his injuries were caused by the negligence of the appellant … in that respect."
35 The respondent was required to establish that the relevant breach caused the loss and damage. The respondent pleaded 10 particulars of negligence one of which was that the City "failed to ensure that the surface below the flying fox was soft and shock absorbent". Further and better particulars of this plea were not requested or provided prior to trial.
36 The trial Judge refers to the City's breach of duty on a number of occasions. She said (at [118]):
(Page 16)
- "It was clearly the duty of the [City] to ensure that the surface below the play equipment was soft and shock absorbent and in that the defendant failed and was negligent."
37 The evidence established that the City called tenders for the supply and construction of two play areas, one with "junior equipment" and the other with "senior equipment", the track ride falling within the latter category. Junior equipment was for the use of children up to the age of seven and senior equipment was for children in the 8-12 year old age group. The successful tenderer was required to construct a sandpit around the junior equipment. Where such sandpits were to be constructed, the contractor was to allow for filling using clean sand to 0.3 m in depth as supplied adjacent to the sandpit by the City. Mr Few, a former technical officer in the design section of the Parks Department of the City, gave evidence that there was also to be a sandpit under the track ride but that was to be done by the City.
The trial Judge makes a further finding at [172] as follows:
"It is my finding that the defendant was negligent in failing to provide sufficient sand. I make the point that one would expect the higher the piece of equipment is, the deeper the sand would be and therefore if it is to be a foot of sand under junior equipment, I would expect under senior equipment to be substantially more than that."
38 Having identified the breach, the trial Judge considered whether that breach caused the respondent's injury. It is necessary to refer to the expert evidence. Mr Lane, an engineering geologist, carried out tests to determine the density of the soil underneath the junior equipment and senior equipment as it was on 9 September 1992. The trial Judge found that the surfaces inspected on 9 September 1992 were the same as on the date of the accident. There is no challenge to that finding. The ground beneath the junior equipment was described as comprising "loose white fine to coarse grained sand with some shells". The ground under the senior equipment was described as comprising a thin layer of loose fine to medium grained yellow sand overlying medium dense to dense grey sand with silt. A number of Perth sand penetrometer tests were carried out and it was determined that the ground beneath the junior equipment could be described as very loose at the surface to 0.15 metres, loose from 0.15 metres to 0.3 metres then medium dense. The ground beneath the senior equipment was described as medium dense from the ground to 0.3 metres becoming dense to very dense below that level.
(Page 17)
39 Mr Lane also carried out pocket penetrometer testing at the two locations to obtain the in situ Youngs Modulus (a measure of the "stiffness" of the ground) which for the loose sand varied from 5 MPa to 20 MPa and for the firm sand, varied from 50 MPa to 100 MPa. The stiffer the ground the higher the force applied to a body to bring it to rest.
40 Mr van der Meer in his reports relies on the Soil & Rock material to conclude that the ground under the track ride on which the respondent was injured was very hard and dense. Further, based on the in situ Youngs Modulus figures he calculated that an object brought to rest by the firm sand would experience a force approximately 2.44 four times greater than that experienced by an object coming to rest in the loose sand. He went further in his oral evidence. He was asked by the trial Judge as to whether the differential of 2.44 was "significant". The witness responded:
"Well, your Honour, that is a - there's a noticeable difference. It can be even greater than that. Had the soft ground been something like beach sand, true beach sand, that figure would've been more in the order of 4 or 5 … the rate of deceleration is important and a body will decelerate faster in hard sand than soft sand."
41 This evidence was not challenged in cross-examination. However, it is not clear how the "loose white fine to coarse grained sand with some shells" differed from true beach sand. Further, Mr Few gave evidence that the sand used by the City for its playgrounds could come from the beach front that the City controlled.
42 The respondent also relied on a written report of the late Mr E R Griffiths, an orthopaedic specialist, to the effect that it was possible that a major injury might have been avoided with a surface of a softer nature.
43 I turn now to the evidence adduced by the City. The purpose of the first ETRS report was to ascertain whether the presence of soft sand would have reduced the injuries to the respondent. The introductory paragraph notes their instructions which were that the respondent, whilst hanging upside down on a horizontal track ride, lost his grip and fell to the ground which was a grassed surface. The calculations in the first ETRS report were carried out on the assumption that there was purely compressive axial impact to the neck.
44 The work involved two stages. The first was to undertake a search of the literature for information as to the loads that a human neck can
(Page 18)
- withstand when the full body mass is suddenly transmitted to the neck. Three papers are relied on. They are (1) Kinematic and Anatomical Analysis of the Human Cervical Spinal Column Under Axial Loading by Pintar et al (2) The Influence of End Condition on Human Cervical Spine Injury Mechanisms by Nightingale et al and (3) Head and Neck Response to Axial Impacts by Alem et al. Based on that research, some of which involved the use of cadavers, ETRS concluded that an impact force of between 6 - 11 kN was required to produce vertical body fractures at C5 and C6 in some specimens.
45 The second stage was a recreation of the accident using a simulated mass and shape that correlated with the respondent's weight and head size. The simulation was performed using a 16 pound 10 pin bowling ball attached to a 64 kilogram steel mass on the rear end of which was an accelerometer. The mass was raised to heights of 0.5, 1, 1.5 and 2 metres. The shape was dropped from these heights to the ground and the deceleration of the mass was determined by the accelerometer reading. The bowling ball end contacted the ground vertically to simulate a human head hitting the ground and compressing the vertebrae under axial compression. The tests were performed on a grassed surface and a soft sand surface. The mass was dropped twice at each height to give an average of the results. The aim was to ascertain the axial load required to produce a compression fracture of the C5 vertebrae.
46 The results of the testing programme for the impacts on grass and sand are as follows:
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47 The results demonstrate that the impact force on grass is substantially higher than on soft sand. As I understand the general position, the softer the impact surface, the greater the impression depth (on the surface material), the longer the distance travelled during deceleration, the smaller the decelerating (and impact) force.
48 The results of the experimental work also show that for both grass and sand, the impact force on the head increased as the height above the ground increased but the increase is not linear. According to ETRS, the height at which the impact force became critical was 0.5 metres for both grass and soft sand because at that height the impact force exceeded the axial loading that would result in the fracture in the C5 vertebrae. That statement was not challenged at trial. In any event, nothing turns on it because of the trial Judge's finding as to the distance of the fall as
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- discussed later in these reasons. The first ETRS report concluded that, from the height the respondent was considered to have fallen, the same injury would have been inflicted whether or not there was soft sand or a grass surface under the track ride.
49 In a letter dated 8 January 1997 (exhibit 54) ETRS advised that the test sand was dry and not compacted in any way and was screeded flat before each test. No information was provided as to the depth of the test sand. The grass used for the test was a couch variety and a new location was used for each test to discount any compaction of the soil after each test.
50 The second ETRS report evaluated the response of the human head and neck to impact on grass and soft sand with the neck in flexion or in extension. Based on a review of medical research, ETRS concluded that the bending moment at the occipital condyles was related to injury to the neck. Kinematic modelling of the impact of a human being with the ground was undertaken using neck measurements from males in a similar age group to the respondent and impact measurements from a mechanical model of the human body. In the kinematic modelling, constant deceleration was used to simplify estimation of the forces and moments that might be experienced. It was found that for a 0.5 metre fall onto sand, the estimated bending moment at the occipital condyles could exceed the injury threshold by the following factors:
In flexion of the neck: 1.82
In extension of the neck: 2.07
51 These values are lower than the corresponding values for impact on grass by 10 to 17 per cent "and some injury reduction may be possible for the scenario where deceleration was constant during the impact". However, the report states that in practice deceleration would not be constant. For non constant deceleration, the estimated bending moments at the occipital condyles could rise to more than twice those values estimated to occur during steady deceleration. In this case, the estimated bending moment at the occipital condyles could exceed the injury threshold by the following factors:
In flexion of the neck: 3.5 or worse
In extension of the neck: 4.0 or worse
52 ETRS concluded in its second report that, with such a large margin over the injury threshold, the substitution of sand for grass under the track
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- ride would not have substantially reduced the injuries to the respondent's neck.
53 Mr Scull is head of the Department of Medical Engineering and Physics at RPH. He is a biomechanical engineer with expertise on biomechanical issues relating to, inter alia, spinal injuries. At the time of giving evidence, he had worked in that area at RPH for over 30 years. He had conducted research and been involved, with orthopaedic surgeons, in clinical studies directed at explaining the causal relationship between particular impacts and damage to the spinal cord. He prepared a written report that was tendered in evidence. The report discloses that he was informed that immediately prior to the accident the respondent was hanging upside down in a crouched position from the triangle of the track ride and that he fell from that position to contact the ground surface head first. Mr Scull confirmed in evidence that his opinion was based upon the respondent dropping vertically onto his head across a range of heights. He calculated the height (distance) of the fall as 970 mm, the velocity at impact at 4.36 metres per second and the duration of the fall at 0.44 seconds. A diagram attached to Mr Scull's report showed the basis of his calculation of the height of the fall. He said in cross-examination that the position of the body in the diagram was not meant to represent in any way the position of the head and neck during the fall or at the point of impact. The purpose of the diagram was to calculate the height of the fall.
54 Mr Scull described the processes at work in a head first fall. He said that the kinetic energy of the body at the point of impact (calculated in accordance with the formula 0.5 x body mass x velocity2) is dissipated as energy absorbed at the impact surface (due to indentation of the surface) and as energy absorbed during the transmission of load within the body. As the energy of impact increases, elements in the chain of energy dissipation (such as the ground surface, the skull, the cervical and thoracic spines) are subject to loading at higher rates. Bone structures respond in an increasingly brittle manner as strain rate increases resulting in bursting (comminution) at failure with a sudden release of stored energy.
55 Mr Scull concluded that the combination of the sagittal fracture of the vertebral body of C6 and the comminuted fracture of the vertical body at C5 were indicative of failure at high strain rate involving an axial component of force (force directed along the axis of the spine) exceeding the vertical strength at the C5/6 level. According to Mr Scull, it was impossible from the information available to describe the impact other than to say that there was a severe impulse delivered to the skull in approximately a superior - inferior direction, that is, effectively a force
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- from the top of the head along the axis of the spine. Although Mr Scull concluded that the predominant force that produced the injury was an axial compression force, that did not exclude the possibility of flexion or extension moments superimposed over and above the axial force, depending on the posture of the body.
56 Mr Scull referred to a number of studies conducted to determine the tolerance of the cervical spine to axial loading, including two referred to in the first ETRS report. Mr Scull had considered the first ETRS report. He agreed in general terms with the estimates provided by ETRS but with the provisos that they had to be used with care because of approximations inherent in the penetration experiment and the use of constant deceleration models. In particular, he noted first, that the ETRS model did not have any resilience that would act to attenuate the impact loads at the ground and secondly, that constant deceleration did not take into account non-linearity in the ground resistance to penetration. Using the results of the experiments conducted by ETRS (where a rigid body was used against a compliant ground surface) and the experiments of Nusholtz (which used a compliant body against a rigid ground surface), Mr Scull calculated the net deceleration for a resilient body impacting a resilient surface. He concluded:
"In that the deceleration of the body into sand is 56% of that into grass with this correction, compared to 49% derived from the ETRS experimental figures it adds further weight to the conservative nature of the estimates provided in the ETRS reports which compare the two situations."
57 Mr Scull's calculation was to estimate the effect of adding body compliance to the rigid model used by ETRS. Based on Mr Scull's calculations, he concluded that the ETRS analysis was conservative and probably understated the trauma imparted by the impact with both surfaces.
58 Based on the description of the trauma incurred by the respondent, Mr Scull concluded that it was probable that:
(a) the primary injury centred on the C5 vertebrae as a result of axial loading of the cervical column at high strain rates which produced a burst fracture of the vertebral body and energy transfer to the adjacent spinal cord as a result of comminution of the vertebral body;
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- (b) the cervical spine was subject to bimodal loading with the primary trauma occurring as a result of energy release early in the impact process prior to the peak of primary deceleration;
(c) the cervical spine was subject to a segmented column failure resulting in complex and sequential secondary trauma involving both flexion and extension mechanisms in the column superior and inferior to the level of primary injury; and
(d) the cervical spine was also subjected to lateral bending and concomitant rotation of spinal elements during the course of impact.
59 Mr Scull commented on the tests undertaken by Mr Lane and the commentary by Mr van der Meer. He said the tests were difficult to relate to the incident. Although they appeared to demonstrate a non-linearity in the response of sand to compression with depth, the total depth of penetration was well beyond that expected with respect to the incident. He also observed that it was probable that a 16 mm diameter penetration rod would elicit a different response from sand or grass to that of an approximately spherical surface with a diameter approximating that of a human head.
60 Mr Scull concluded:
"Because of the complex dynamics involved, I cannot exclude the possibility that [the respondent] would have been spared the severe injuries incurred by the impact on a grass surface had he sustained a similar fall onto sand. One cannot exclude the possibility that a different fall under similar conditions onto sand could have produced a different complex of injuries with a worse prognosis.
It is my opinion however that, because of the severe nature of the impact and the predisposition of the cervical spine to trauma under such an impact it is highly unlikely that an identical impact on sand would not have caused a significant injury. In the event that the shock attenuation offered by sand, as evidenced by the reduction in peak deceleration at impact when compared with that for the grass surface, was sufficient to ameliorate the primary injury attributed to the burst fracture of the body of C5, it is still probable that the secondary injuries associated with axial compression – flexion loading of the spine
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- and lateral bending – rotation would have caused injuries sufficient to compromise the spinal cord (eg. injuries such as fracture dislocation, vertebral subluxation and ligamentous tears, etc.) resulting in quadriplegia."
61 Mr Scull confirmed in examination in chief that he could not exclude the possibility of a better or worse outcome if the respondent had fallen onto soft sand. However, he concluded that there was a high probability that there would have been a similar injury to the spinal cord resulting in quadriplegia even if the respondent had fallen onto soft sand. Mr Scull was not challenged on the central aspects of his evidence. The cross-examination was directed at showing that if the respondent had fallen in a continuous somersault motion, 0.3 m of sand underneath the track would have changed the height of the fall and the injuries may have been different.
62 Mr Hardcastle provided two written reports. In his first report he stated that a person falling from a particular height landing on soft beach-like sand was much less likely to sustain the severe injuries that the respondent sustained when landing on hard sand. After Mr Hardcastle was provided with Mr Scull's report and the studies by Pintar, Nightingale and Alem, he changed his opinion. His conclusion is as follows:
"It would be my opinion that the conclusions drawn by Mr Scull 'because of the severe nature of the impact and the predisposition of cervical spine to trauma under such an impact [it] is highly unlikely that an identical impact on sand would not have caused a significant injury'.
Based on the evidence provided … one would have to conclude by saying that the surface underneath the flying fox be it sand (impacted or soft) or grass is highly unlikely to have made any difference to the nature of his cervical injury. It is an extremely severe injury … and therefore unfortunately I would have [to] conclude by supporting Mr Scull's opinion."
63 Mr Hardcastle was not cross-examined on the central issues. However, it emerged from cross-examination that he did not regard himself as an expert in the calculation and effect of impact forces and he deferred to the opinion of Mr Scull.
64 Mr Batalin stated in his report that he believed the force resulting in the respondent's injuries would have been very significant and that "it
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- would not have made much difference if the underlying ground was sand, turf or - for that matter - most other weight bearing materials".
65 In his oral evidence, Mr Batalin accepted that different surfaces have different absorption rates with different potential for injury. He continued (at T 1281):
"In this particular case looking at the damage, the severity of forces needed I don't think would have made much difference if it was sand or grass or – it may have made some difference, I don't know. I'm only guessing now and I am saying that loudly."
66 Subsequently he said that if the surface had been soft sand there would have been a somewhat similar injury, perhaps not as many vertebrae involved "but I don't think basically it would’ve made a difference as far as quadriplegia is concerned".
67 The trial Judge in her reasons refers to aspects of the expert evidence save for that of Mr Batalin. She only quotes from the second ETRS report including the conclusion that sand would not have substantially reduced the injuries and in effect dismisses the ETRS reports with the following comment (at [160]):
"It can be seen that what ETRS has done is compared grass with flat sand. No tests have been done on a foot or more of loose beach sand … in a depression."
68 The trial Judge then refers to Mr Scull's evidence and concludes (at [170]):
"It can be seen from all of this evidence that there is even with sand which is screed flat taking ETRS figures together with the comments made by Mr Scull the deceleration of the body into sand is 56 per cent of that into grass. Accordingly if there was a foot or more of loose beach sand the reductions would have even been greater. I have not been given what they would be but sufficient probably to prevent this injury."
69 She then refers to her finding that the City was negligent in failing to provide "sufficient sand" being substantially more than a foot of sand because the track ride was senior equipment and concludes that she was satisfied on the probabilities that the breach of duty caused the respondent's injuries and certainly materially contributed to them, relying
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- on The State of Western Australia v Watson [1990] WAR 248 and McGhee v National Coal Board [1973] 1 WLR 1.
Causation principles
70 A defendant is liable in negligence only if the damage suffered by the plaintiff was caused by the defendant's negligent act or omission. The legal onus of proof of causation is, and remains, on the plaintiff.
71 However, the negligent act or omission need not be the sole cause of the damage. This is reflected in the classic statement that causation will be established if the negligent act or omission caused or "materially contributed to" the damage.
72 Causation does not have to be established by direct evidence; regard can be had to objective facts, probabilities and inferences: Rosenberg v Percival (2001) 205 CLR 434 at 449 per McHugh J; at 460 - 465 per Gummow J.
73 Generally, the issue of causation is divided into two questions: the question of causation in fact which is generally determined by the application of the "but for" test and a further question of whether the defendant is in law causally responsible for the damage. This is reflected in the judgment of Mason CJ, Deane and Toohey JJ in Bennett v Minister for Community Welfare (1992) 176 CLR 408 (at 412 - 413):
"In the realm of negligence, causation is essentially a question of fact, to be resolved as a matter of common sense. In resolving that question, the 'but for' test, applied as a negative criterion of causation, has an important role to play but it is not a comprehensive and exclusive test of causation; value judgments and policy considerations necessarily intrude." (footnotes omitted)
74 Generally, a plaintiff will fail if he cannot satisfy the "but for" test. However, there are some situations where causation can be established without satisfying the "but for" test. That occurs, for example, where there are multiple sufficient causes resulting in indivisible damage. Further, in the United Kingdom, the failure to satisfy the "but for" test of causation is not determinative where there is an evidential gap. That will occur where there is positive evidence that on the current state of knowledge in the relevant area, experts are unable to say whether the damage would or would not have been suffered but for the negligent act and omission. McGhee v The National Coal Board (supra) referred to by
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- the trial Judge is such a case. After a short period of working in brick kilns, the plaintiff worker suffered dermatitis. The Court found that the employer had breached its duty of care by failing to provide adequate washing facilities at the workplace. The question before the House of Lords was whether the worker had proved that the breach caused the dermatitis. The evidence established that the provision (and use) of washing facilities would have materially reduced the risk of dermatitis. If the evidence was left there (and provided the Court found that the worker would have used the facilities) the Court could have drawn an inference that the breach caused the dermatitis. However, the evidence did not stop there. None of the medical experts called at the trial would go so far as to say that washing after work would have made it more probable than not that the worker would not have contracted dermatitis. The state of medical knowledge at the time did not allow the medical experts to reach a conclusion on the question. Thus, the worker had not proven on the balance of probabilities that the damage would not have occurred but for the negligent omission. Different members of the Court provided different reasons for concluding that the worker had established causation. The judgment of Lord Wilberforce in McGhee has been relied upon by the High Court. Lord Wilberforce said (at 6):
" … I agree with the judge below to the extent that merely to show that a breach of duty increases the risk of harm is not, in abstracto, enough to enable the pursuer to succeed. He might, on this basis, still be met by successful defences …
But the question remains whether a pursuer must necessarily fail if, after he has shown a breach of duty, involving an increase of risk of disease, he cannot possibly prove that this increase of risk caused or materially contributed to the disease while his employers cannot positively prove the contrary. In this intermediate case there is an appearance of logic in the view that the pursuer, on whom the onus lies, should fail … The question is whether we should be satisfied in factual situations like the present, with this logical approach. In my opinion, there are further considerations of importance. First, it is a sound principle that where a person has, by breach of duty of care, created a risk, and injury occurs within the area of that risk, the loss should be borne by him unless he shows that it had some other cause. Secondly, from the evidential point of view, one may ask, why should a man who is able to show that his employer should have taken certain precautions, because without them there is a risk, or an added risk, of injury or
- disease, and who in fact sustains exactly that injury or disease, have to assume the burden of proving more: namely, that it was the addition to the risk, caused by the breach of duty, which caused or materially contributed to the injury? In many cases of which the present is typical, this is impossible to prove, just because honest medical opinion cannot segregate the causes of an illness between compound causes."
75 In the subsequent case of Fairchild v Glenhaven Funeral Services Ltd [2003] 1 AC 32 the House of Lords concluded that in limited circumstances, of which McGhee was an example, there were exceptions to the ordinary rule requiring proof on the balance of probabilities of causation in fact. In Fairchild, the appellant employees had developed mesothelioma as a result of exposure to asbestos dust during periods of employment with more than one employer. The workers could not establish on the balance of probabilities which of the employers had exposed the employees to the asbestos dust that caused the disease. The mechanism initiating the disease process was unknown and (importantly) once caused, the condition was not aggravated by further exposure. However, the greater the quantity of fibres inhaled, the greater the risk of developing the disease. Mesothelioma was determined to be an indivisible disease. The workers had not proven that, but for the exposure in the course of employment by each individual employer, they would not have contracted the disease. The House of Lords held that the evidential gap justified a modified approach to proof of causation; in such a case, proof that each defendant's wrongdoing had materially increased the risk of contracting the disease was sufficient to satisfy the causal requirement for liability.
76 The House of Lords in McGhee and Fairchild was concerned with evidential gaps that could not be filled by either party. However, if the disease was one which was aggravated (made worse) by further exposure, that would justify a factual finding that a particular contribution from a particular source materially contributed to the disease: Bonnington Castings Ltd v Wardlaw [1956] AC 613; Nicholson v Atlas Steel Foundry & Engineering Co Ltd (1957) 1 WLR 613.
77 A number of members of the High Court, relying on the judgment of Wilberforce J in McGhee, support a rule that on its face applies to proof of causation generally (it not being confined to evidential gaps that cannot be filled by either side). The approach is reflected in the oft-cited statement of Gaudron J in Bennettv Minister for Community Welfare (at 420 - 421):
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- " … generally speaking, if an injury occurs within an area of foreseeable risk, then, in the absence of evidence that the breach had no effect, or that the injury would have occurred even if the duty had been performed, it will be taken that the breach of the common law duty caused or materially contributed to the injury". (footnotes omitted)
78 Gaudron J links breach and causation. She said in Bennett (at 422) that there is usually no reason to separate or distinguish the question of breach of common law duty from that of causation because the duty relates to precautions a reasonable person in the position of the person sued would have taken to prevent a foreseeable risk of harm of the kind suffered and a precaution would not be classified as reasonable unless its performance would, in the ordinary course of events, avert the risk that called it into existence.
79 Gaudron J's statement at 420 - 421 in Bennett has been cited with approval in Chappel v Hart (1998) 195 CLR 232 at 239 per Gaudron J; at 247 per McHugh J (cf at 244); at 257 per Gummow J; and at 273 per Kirby J; Rosenberg v Percival (supra) at 461 per Gummow J; Naxakis v Western General Hospital (1999) 197 CLR 269 at 279 per Gaudron J. Any suggestion that Gaudron J's statement contemplates the legal burden shifting to the defendant is rejected by McHugh and Kirby JJ in Chappel v Hart (at [68] and [93]).
80 As I understand the law in Australia, once a plaintiff demonstrates that a breach of duty has occurred followed by injury within the area of the foreseeable risk, a prima facie causal connection will be established and the defendant has an evidential burden to show that the breach had no effect. However, once there is evidence sufficient to displace the plaintiff's prima facie case, it remains 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: Purkess v Crittenden (1965) 114 CLR 164 at 168.
Causation analysis
81 The central question is whether the respondent proved on the balance of probabilities that the injuries would not have occurred if the appellant had complied with its duty to provide soft sand under the track ride. There is no suggestion that the respondent was not required to establish causation in fact.
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82 The first task is to identify the relevant "injury". The appellant contends that the case was fought by the parties on the basis that the injury was the respondent's quadriplegia, not the individual fractures and other damage or indeed, the severity of the quadriplegia. The respondent did not challenge that assertion and it is justified by the record. That is, the matter was approached on the basis that the relevant injury was the respondent's quadriplegia and that it was indivisible.
83 There is a factual foundation for this approach. The evidence, scant though it is, does not support a finding that soft sand would prevent, or eliminate the risk of, all injuries. All it does is reduce the risk of severe injury. This is borne out by papers in the City's possession that were tendered in evidence. For example, in a paper entitled "Australian Standards for Playgrounds", Mr H Blenk states that the aim is to minimise hazards and in relation to "undersurfacing", a safe fall is stated to be the prevention of brain damage not fractures. This is consistent with a paper prepared by the Safety Coordinator of the Education Department of Western Australia in which it is noted that protective or impact absorptive surfaces may not have reduced the number of injuries from falls but those materials "may have reduced the severity of the injuries".
84 Thus, the evidence goes no further than establishing that soft sand reduces the risk of severe injuries from a fall from playground equipment. That is consistent with all the expert evidence that there is an inverse relationship between the impact force and the absorption capacity of the surface. Subject to one qualification, it can be said that the respondent established a prima facie case that the City's omission caused or materially contributed to the respondent's quadriplegia.
85 The qualification relates to the appropriate depth of soft sand. The City's concession is limited to sand of a depth of around 300 mm. There is no expert or scientific evidence on which to make a finding as to the necessary or appropriate depth of sand under the track ride. What evidence there is relates solely to what is required for playground equipment used by children up to 12 years. The figure of 300 mm is taken from the City's own documents (prepared by Mr Few) which assert that the appropriate depth of soft sand for a fall from 3 metres (the track ride was 2.5 m high) was 300 mm. However, it is clear that that is the depth the City thought appropriate for intended users of that equipment, being children aged between 8 and 12 years. From my examination of the record, no consideration was given by the parties or the trial Judge to whether the depth of sand required to minimise the risk of harm to an adult is greater than what is required to achieve equivalent protection for a
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- child, and if so, whether reasonableness required the City to provide sufficient sand to protect adults. Based on the scanty evidence, the answer to the first question is likely to be yes because the greater a person's weight and the higher the velocity of the fall, the higher the impact force.
86 The second question of what reasonableness required was not expressly addressed. However, the only evidence to support a finding on the question of breach related to safety measures to protect children. On one view, the issue decided by the trial Judge was whether the failure to provide soft sand for the intended users (children between 8 and 12) caused or materially contributed to the respondent's injuries. I would have significant reservations as to the correctness of that approach. At the very least, a moment's reflection might suggest that a court would be less willing to draw an inference that an omission which materially increased the risk of severe injury to children caused or contributed to injuries suffered by an adult. However, it appears the case was conducted and decided on the unstated (and unchallenged) assumption that the standard of care for adults (or more specifically, the appropriate depth of soft sand) is the same as that for children. If it were otherwise, I would have great difficulty with a proposition that reasonableness required a local government authority to adopt safety standards and measures to protect adults who may use children's playground equipment. However, I will proceed on the basis of the assumption, in which event the evidence establishes a prima facie case of causation. That being so, the next question is whether the appellant discharged its evidentiary onus of adducing evidence that the injury would have occurred even if soft sand had been provided. In my view, the evidence of Mr Scull and the ETRS reports satisfy the evidentiary burden. Accordingly, the issue is whether the respondent, on the whole of the evidence, established that the omission to provide soft sand caused or materially contributed to his quadriplegia.
87 Counsel for the respondent in the appeal (who was also counsel at trial) sought to challenge the relevance of, and weight to be given to, the ETRS reports and the evidence of Mr Scull. He contended that the ETRS reports were irrelevant or ought to be given no weight for a number of reasons. First, it was said that the reports were based on irrelevant assumptions as to how the respondent fell. The first and second reports were based on different assumptions. The first report is based on the assumption that the respondent fell in an upside down position a distance of between 0.5 and 2 metres straight onto the top of his head thereby compressing his vertebrae under axial compression. Whether or not the
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- respondent had intentionally placed himself in an upside down position before falling or whether he fell from an upside down position as a result of his partial somersault is irrelevant. For the reasons given earlier, the trial Judge's finding is only consistent with the appellant falling head first from a distance of at least 970 mm. I see no material difference between the trial Judge's finding as to how the accident occurred and the assumptions in the first report. The same conclusion applies to Mr Scull's assessment that the respondent fell head first from a height of 970 mm.
88 The assumptions in the second ETRS report are that the respondent's head was in flexion (forward towards his chest) or extension (backwards) at the time his head hit the surface. That is inconsistent with the medical evidence, Mr Scull's evidence and the trial Judge's finding that the respondent fell directly onto the top of his head. In those circumstances only the first ETRS report is relevant.
89 Secondly, the respondent contended that the ETRS results were irrelevant or should be given no weight because the testing methods did not replicate a human body. That is a matter that ought to have been put to the author of the report to give him the opportunity of answering it. In any event, the matter was expressly addressed by Mr Scull who confirmed that the ETRS modelling in the first report was conservative. Further, Mr Scull did his own calculations to allow for body compliance and reached the same conclusion as the first ETRS report, namely the respondent would have suffered quadriplegia even if he had fallen onto soft sand. Mr Scull's evidence on this subject was not challenged by the respondent in cross-examination. It is too late to put propositions to this Court that should have been put to witnesses at trial for their response.
90 Thirdly, the respondent says there was no evidence as to the depth or type of soft sand used in the ETRS tests. The ETRS reports were tendered by consent with counsel for the respondent's agreement that the reference in the reports to soft sand was a reference to soft, white beach sand and that the grass surface was grass on sand (at T 1027). The only matter on which there was no evidence was the depth of the soft sand on which the tests were conducted. It was no part of the respondent's pleaded case or his case as put to any relevant expert at trial that the soft sand should be to any particular depth. Further, the experts were not questioned about the relevant factors in determining the appropriate depth of soft sand or whether depth became irrelevant after a certain point. There is evidence from Mr van der Meer (at T 294) that suggests the depth of absorbent material affects the behaviour of the material at the surface (implying that the greater the depth of soft sand, the greater the depth of penetration of
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- the head, the greater deceleration time and a consequential reduction in the peak impact force). That sounds sensible. But whether, and if so at what depth, that effect ceases is unknown.
91 Having regard to the way in which the respondent conducted his case and to Mr Scull's skills and very extensive experience in this area, it would be expected that if there was a deficiency in the modelling undertaken by ETRS, such as for example the use of inadequate soft sand, Mr Scull would not have described ETRS's results as conservative and would not himself have concluded that soft sand would make no material difference to the respondent's injuries. In those circumstances, I see no proper basis on which to conclude that Mr Scull's conclusion or that of ETRS is impaired because of a failure to conduct the tests on the appropriate level of soft sand (whatever that may be).
92 Fourthly, the respondent says the ETRS reports should be given no weight because the tests were on grass whereas the trial Judge found that the appellant fell on the surface described and tested by Mr Lane. There is no evidence that there was a material difference between the impact force on "grass on sand" and the surface described by Mr Lane as medium dense. In any event, the relevant comparison is between the impact force required to cause quadriplegia (based on the experimental results reported by others) and the impact force of the respondent falling head first onto soft sand.
93 Finally, the respondent challenges the relevance and applicability of the experiments reported in the papers relied on by ETRS in its first report and the ETRS conclusion based on them. The time to do that was at trial. Mr Scull, who had the requisite skill and experience to comment on the reported experiments, had regard to some of the same papers as ETRS and others by the same authors in reaching his own conclusions on the subject. None of the specific matters raised in the appeal were put to Mr Scull and there was no challenge to his evidence.
94 None of the matters raised by the respondent in the appeal justify a conclusion that the ETRS reports or Mr Scull's evidence are irrelevant or should be given no weight.
95 As previously noted, the respondent's cross-examination of Mr Scull was directed at showing that if the respondent was in the course of somersaulting during the fall and there was 0.3 metres of sand underneath the track ride, the height of the fall and the nature and extent of the injuries would be different. That may be so but it does not establish
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- causation. The trial Judge found that soft sand was reasonably necessary as a means of cushioning the impact of the fall. It was no part of the respondent's case (and the evidence does not justify a finding) that the purpose of the soft sand was to reduce the height of the fall. No doubt there could be an appropriate depth of soft sand below ground level. In any event, the respondent is required to establish that the justification for the precaution, in this case cushioning the impact of a fall, is causally connected with the injuries. That sand may in some circumstances alter the distance of a fall is, in this case, mere serendipity that is unrelated to the justification for using soft sand and is causally irrelevant: see Henville v Walker (2001) 206 CLR 459 at [102] per McHugh J.
96 The trial Judge dismissed the ETRS reports because the experiments were not conducted on a "foot or more of loose beach sand". The reference to beach sand ignores the respondent's agreement at the time the reports were tendered that the soft sand in the experiments was soft white beach sand. Her implicit conclusion that a foot or more of sand was required is not supported by any expert or scientific evidence. In any event, I have concluded that the absence of information on depth is not a proper basis to impugn the adequacy of the ETRS modelling or Mr Scull's conclusion. Further, although Mr Scull (and all the other experts) concluded that the impact force on soft sand is less than on harder surfaces, that does not support the trial Judge's finding that a foot or more of loose beach sand was "sufficient probably to prevent this injury". That finding is against the overwhelming weight of the evidence. It is inconsistent with Mr Scull's evidence which supports the correctness of the ETRS conclusions. Although Mr Hardcastle supports Mr Scull's conclusion, there is some doubt as to his expertise. Mr Batalin's evidence may be seen as providing only equivocal support for Mr Scull's conclusion but it does not support the contrary position, namely, that the respondent would not have been rendered a quadriplegic if soft sand had been placed under the track ride. Further, none of the respondent's experts gave evidence to that effect.
97 It is the case that the absence of soft sand significantly increased the impact force on the respondent's head and spine and, on the balance of probabilities, increased the number of individual fractures and other injuries. In this sense, the City's omission worsened the injuries he would have suffered in any event. In ordinary circumstances that may justify a finding that the City's breach aggravated the injuries and thereby materially contributed to the harm. But in the way this case was conducted the relevant injury was quadriplegia which the evidence established would have resulted whether or not the City breached its duty.
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- There was no suggestion by the parties (or evidence) that there are different levels of seriousness or gravity of quadriplegia. Thus, the City's breach was not a cause of the whole injury; that is, it did not make a material contribution to the respondent's quadriplegia. If the respondent's case had been that the breach aggravated the non-breach related injuries, issues of apportionment may have arisen: see I & L Securities Pty Ltd v HTW Valuers (Brisbane) Pty Ltd (2002) 210 CLR 109 at 120 - 121 [29] - [31] per Gleeson CJ; Thompson v Smiths Shiprepairers (North Shields) Ltd [1984] QB 405 at 437 - 444; Stapleton, Cause-in-Fact and the Scope of Liability for Consequences (2003) 119 LQR 388. I would uphold grounds 7 and 8.
Conclusion
98 The clear weight of the expert evidence establishes, on the balance of probabilities, that the respondent would have suffered injuries resulting in quadriplegia even if he had fallen onto soft sand. I am satisfied that the trial Judge erred in concluding that the City's failure to provide soft sand caused or materially contributed to the respondent's quadriplegia. For these reasons, I would allow the appeal, set aside the orders made by the trial Judge and order that the respondent's claim against the City be dismissed.
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