Workers' Compensation and Rehabilitation Act 1981, s 86, s 93D

Abalos v Australian Postal Commission [1990] HCA 47; (1990) 171 CLR 167

Agbaba v Witter (1977) 14 ALR 187

Betts v Whittingslowe [1945] HCA 31; (1945) 71 CLR 637

Brunskill v Sovereign Marine & General Insurance Co Ltd [1985] HCA 61; (1985) 62 ALR 53

Chambers v Jobling (1986) 7 NSWLR 1

Galea v Galea (1990) 19 NSWLR 263

Gray v Motor Accident Commission (1998) 196 CLR 1

Herald & Weekly Times Ltd v McGregor [1928] HCA 36; (1928) 41 CLR 254

Lamb v Cotogno [1987] HCA 47; (1987) 164 CLR 1; 74 ALR 188

Naxakis v Western General Hospital [1999] HCA 22; (1999) 197 CLR 269

Neat Holdings Pty Ltd v Karajan Holdings Pty Ltd [1992] HCA 66; (1992) 110 ALR 449

SS Hontestroom v SS Sagaporack [1927] AC 37

Sutherland Shire Council v Heyman [1985] HCA 41; (1985) 157 CLR 424

Uranerz (Aust) Pty Ltd v Hale (1980) 30 ALR 193

Warren v Coombes [1979] HCA 9; (1979) 142 CLR 531

Wilson v Peisley (1975) 7 ALR 571

Wing Luck Foods v Lay Choo Lim [1989] WAR 358

1 MURRAY J: I have had the advantage of reading in draft the reasons for decision to be published by Hasluck J. There is nothing that I could usefully add to them.

2 I too would allow the appeal to the extent required to reduce the damages by the sum of $10,000 awarded by the trial Judge as aggravated damages. I would dismiss the cross-appeal.

3 PARKER J: I have had the advantage of reading in draft the reasons of Hasluck J with which I generally agree. For those reasons the award should be varied as he proposes.

4 In this case the learned trial Judge was faced with evidence which involved much inconsistency and conflict on many fronts. It was a case in which the trial Judge had a significant advantage because of his first hand observation of the witnesses as their evidence was given. While some of the evidence, if accepted, would have required a different outcome of the trial, it has not been shown that the trial Judge omitted to consider or failed properly to weigh this evidence. The advantage he enjoyed in evaluating it led him to prefer other evidence which was capable of sustaining the respondent's case. Nothing has been raised which would justify interfering with his Honour's factual findings.

5 HASLUCK J: The appellant, Delta Corporation Ltd, is a manufacturer of concrete slabs and railway sleepers. The respondent, Mark Anthony Davies, alleged that on 29 July 1993 in the course of his employment he was using a 4" grinder with an attached steel wire brush when bristles from the brush suffered severe breakage and entered his body. These events were described in the respondent's statement of claim as "the accident".

6 Many years later, on 10 August 2001, his Honour Judge Williams in the District Court at Perth held that the accident was caused by the negligence of the appellant and that as a result of the accident the respondent suffered injuries, loss and damage. Judgment was entered for the respondent in the sum of $725,184.60.

7 The central issue raised by this appeal is whether the evidence adduced by the respondent at trial was sufficient to enable the trial Judge to find, as he did, that on the balance of probabilities the accident and

related injuries occurred as alleged. The central issue embraces a number of subsidiary issues including the question of whether the injuries were self-inflicted and whether all or most of the bristles said to be responsible for the subsequent treatment entered the respondent's body on the day of the accident. The notice of appeal and related notice of contention also raise issues concerning the assessment of damages.

8 I am obliged to note at the outset that the Workers' Compensation and Rehabilitation Act 1981, as it was when the respondent commenced proceedings, has had a bearing upon the way in which the disputed issues were addressed at trial and on appeal. Section 86 of the Act provides that nothing in the act affects any liability that exists independently of the Act. However, the effect of s 93D of the Act was that proceedings in which damages at common law were sought were not to be commenced without the leave of the District Court. I understand from information provided by counsel during the course of the hearing on appeal that in these proceedings leave was obtained in respect of a claim for damages arising out of the accident defined in the statement of claim. This meant that it was not open to the respondent at trial or on appeal to seek relief in respect of any occasion subsequent to 29 July 1993 on which bristles may have entered his body. The significance of this procedural limitation will become apparent later. For the moment, I simply note in passing that the hearings at trial and on appeal were conducted on the assumption that the respondent was obliged to establish that the injuries he complains of and resultant treatment were essentially an outcome of the accident on 29 July 1993.

9 The respondent was born on 23 March 1971. He attended primary school and secondary school and left school at the end of Year 11. In February 1988 he commenced employment with the appellant. The manufacture of the appellant's concrete products involved the use of moulds into which concrete was poured. The respondent's duties included the cleaning of these moulds with brushes attached to angle grinders. The respondent was married in November 1991 and divorced in 1998. He has no children.

10 Two years prior to the accident complained of, on 8 November 1990, whilst the respondent was working in the stress floor section of the appellant's business, cleaning a mould with a wire brush, he felt things hitting him and he had a bad pain in his leg. He reported to his supervisor and was told to go and see the doctor. He subsequently attended at the St Andrew's Medical Group in Midland where he had a wire bristle removed from his leg. He also had a wire bristle removed from his hand on that or another occasion.

11 As at 29 July 1993 the respondent was working in the precast one section of the appellant's business which produced concrete sleepers. After sleepers were removed from a mould there followed a process of cleaning the hardened slurry from the inside of the mould. This involved the use of steel brushes attached to angle grinders.

12 The respondent commenced work on the day in question at 6.30 am. He said in evidence that

"I had long pants on, steel cap boots, a shirt, a jumper with no sleeves and my blue jacket; the zip was broken. The jacket was old; it had rips in, tears in it."

13 There was some discussion in his presence about the unsuitable standard of the sleepers. The upshot was that the respondent was told by the appellant's acting foreman, Allan Foskett, to get a wire brush and to clean the relevant mould.

14 The respondent was previously only familiar with a 9" grinder and brush and was accustomed to using the grinder horizontally. He asked for a smaller angle grinder, because if he used a 9" angle grinder and brush and something happened he would be in a lot of trouble because of the confined area. About ten minutes later Mr Foskett returned with a small brush and told him to attach it to a 4" grinder. He said in evidence that the brush did not have a safety skirt. It looked as though it was brand new but he could see what appeared to be "brown fragments on it" that looked "like rust". He proceeded with the task by working with one foot inside the mould and one foot outside. He had to use the angle grinder vertically and his whole body was in line with it.

"So you were using that. Now describe what happened?---I was working and I felt stuff hit me and I felt a prick near my nose area so I stopped and I went and put a pair of safety glasses on as well as a face mask and continued working and a short time after that I felt a tap on my shoulder so I turned the grinder off and it ran down.

What did you observe?---I noticed that the wire brush had a lot of bristles missing from it. The brush wasn't useable again.

Can you describe how much of it was---?---About two-thirds of it was missing.

Right, and during the course of using it did you notice anything in particular?---Yes. I felt stuff hit me from my feet up to here.

Up to just above your eyes?---Yes.

And when you say felt stuff hit you, can you describe the sensation?---Just like going to a beach and, you know, on a windy day you get hit by sand. That's what it felt like.

All right, so Mr Foskett comes across and what does he do?---He taps me on the shoulder.

Yes?---I turn the machine off and he tells me to carry on because we're running behind, so I turned it off, put it away and carried on working and I had a pain in my right forearm and it just kept on getting worse so I called Craig Walton over and he helped me remove my jacket and I was just feeling and I felt something underneath my skin."

16 Mr Foskett was called as a witness for the appellant. In the course of his evidence in chief he said that he had been working with the appellant for 20 years and was presently employed as a forklift driver. He confirmed that as at 29 July 1993 he was in the position of acting foreman and in that capacity had requisitioned the brush to be attached to the grinder from the storeman. It was a "brand new brush". The brush was returned to him after the incident involving the respondent. He was aware of a report that wire bristles had entered the respondent's body.

17 In the course of his evidence in chief Mr Foskett also said this:

"What did you notice about the brush? --Not a terrific amount.

Were there bristles missing and that you could see?---Yes, well, you could see some missing.

Many?---Didn't appear to be.

What else did you notice about the brush?---It had flared to what it did when it was new.

Is that usual? --That's normal.

What happened to the brush?---I put it in the bottom drawer of my desk and it sat there for a fair - I don't know how long but for a long time.

Do you know what happened to it after that?---No idea."

18 Under cross examination Mr Foskett said he was not sure who reported the incident to him. He could not recall going to the respondent while he was using the brush and asking him to stop. He could not recall being approached by a union representative named Kennedy concerning the whereabouts of the brush and to his knowledge no request for the same was made by the insurance companies involved in the matter. The brush remained in the bottom drawer of his desk for what could have been "a couple of months" but he could not say when it disappeared

19 Mr Foskett then participated in this exchange with counsel:

"Did you continue to use the desk? --Yes.

When did you stop using the desk, how long after do you say it disappeared?---I don't know. As an acting foreman I was sort of in and out of there a couple of times. I'm sorry.

Now, I understand - we have heard a number of witnesses saying that they had had situations where wire bristles off brushes had penetrated their skin and penetrated their flesh in fact. Is that something that was known to you at the time of this incident?---I've had one.

You have had one?---Yes.

Where has yours penetrated?---Just on the - just below the knee and to the side of my leg just below the knee.

Do you know Mr Stannard?---Yes.

I think he has had several instances of wire brush penetrations. Is that right?---I have no idea.

But it was a well-known hazard on site that you could get these bristles penetrate you, wasn't it?---Yes.

There was a system of reporting accidents in a first aid book on site. Do you recall that?---That's right.

I think from time to time the fact that wire had penetrated someone's flesh was noted. Would you agree with that?---I don't know what - I have no idea what was in the book. I never had access to it.

I see. What were the circumstances when you had your piece of wire penetrate your flesh?---I didn't even know it was there and I was having a shower that night and I run my leg and found it was there."

20 As this passage of cross examination suggests, the respondent called a number of witnesses at the trial of the action, being mostly fellow employees, who gave evidence concerning the penetration of wire bristles.

21 Mr Kuvekalovic spoke of discovering a wire fragment from a brush used at work to clean moulds whilst having a shower at home after work. He noticed half way down his thigh on his left leg a pimply mark. When he pressed it a wire bristle protruded whereupon he pulled it out and it was "about 25 mil long". He was not aware how it had got there and according to him it could have happened "at any time". He was in the habit of wearing baggy shorts.

22 Henry Fedec spoke of being hit with wire fragments from the brushes "all the time" including an occasion when a fragment went through his jeans and hit him in the genital area. He was able to go to the toilet immediately and remove it with his fingers as he had felt the impact. It had not penetrated too far.

23 Peter Sarich spoke of being hit with wire fragments from brushes used at the Delta premises and that this involved penetration of the skin and "sometimes you don't even realise it's there." When he had a shower in the evenings he would observe wire poking out and he would proceed to cut it out or pull it out. He said under cross examination that there was one occasion in which he received quite a long bristle in the testicle but without feeling it go in.

24 The appellant's younger brother, Kevin Davies, spoke of wire bristles penetrating his flesh on two occasions. The first one was between his left index finger and left middle finger. The other occasion was when he was at home having a shower and felt one sticking out. It was "probably 12 mil" with about half the length protruding.

25 Darryl Kennedy worked for the appellant from 1988 to 1995 and was also a shop steward with the BLF which had some coverage in relation to Delta Corporation Ltd. When he heard of the incident involving the respondent he approached Mr Foskett and was told "the wire brush exploded". Mr Kennedy, with a view to raising the matter with the Safety Committee, asked if he could take the brush away but was refused permission. When asked in the course of his evidence in chief to describe the appearance of the wire brush in Mr Foskett's possession, the witness said:

"It was about three-quarters, half to three-quarters, with the wire bristles missing."

26 Under cross examination, he went on to say that it was a "newish brush" but "with probably a little bit of rust on it." When pressed, he denied that there were only a few bristles missing and went on to confirm his evidence in chief bearing upon this point.

27 Having reported a pain in his right arm on 29 July 1993, the respondent was told to go and see a doctor. He saw a Doctor Gallagher at St Andrew's Medical Group in Midland. He was X-rayed and bristles were noted in his arm. He was referred to a general surgeon, Mr Clarke, who removed the fibres from his right arm. That was done under a general anaesthetic and he was discharged. The following day he had a sore throat and so he returned to the doctor and an X-ray showed another bristle. He had a second operation to the right side of his neck under general anaesthetic. He then returned to work.

28 At that time the respondent was playing Sunday league football and noticed a lot of pain. He went back to his general practitioner, Dr Wheedon. The doctor took further X-rays and found more bristles. On 10 September 1993 the bristles were removed at St Anne's Hospital by Mr Clarke. The respondent's then wife kept records of his various hospital attendances and the number of wires. After that he returned to work and worked near other persons using brushes but he refused to use a wire brush again.

29 On 23 December 1993 the respondent attended upon Mr Clarke complaining of neck pain and shoulder pain. Mr Clarke gave him a medical certificate. The respondent said that he was feeling sharp jabs over the whole of his body. On 4 July 1994 three further wires were removed.

30 On 17 January 1995 Mr Clarke wrote to the appellant in the following terms:

"Mark has asked me to write to you with respect to the multiple operations which he is having to undergo for wire bristle implantations suffered at work on 29th of July, 1993.

You'll appreciate that these wire bristles are sharp and extremely fine. It creates considerable problems to try and identify whether or not there are any further bristles inside him. Straight X-rays have not been effective in identifying all the little wire bristles. He's had a CT scan and this too has failed to positively identify the wire bristles. The problem is that when they are so fine that if they lie end-on to the X-ray or if they over-lie the bones then they simply cannot be seen at that particular time by that particular X-ray. These bristles being so sharp have a tendency to migrate into new positions and as they do Mark recognises symptoms from this and they are usually able to be detected with X-ray and then removed surgically.

I wish that there was a magic X-ray or other machine that would positively identify every single last bristle within him such that he wouldn't need to continue to undergo repeated operations, however, such machinery doesn't exist and for the foreseeable future until the last bristle is finally removed Mark is going to have to undergo further X-rays and surgery as each new symptomatic bristle comes to light.

It's a very difficult situation obviously for all concerned. Mark wanted me to explain the situation to you to highlight the genuine nature of his problem so that he can have your on-going support as he faces each operation."

31 Mr Clarke's 1995 report was not the end of the matter by any means. It simply set the scene for what proved to be an arduous course of events during the course of which further bristles were removed from the respondent's body and with the respondent being obliged to seek psychiatric and psychological assistance. Eventually his wife told him that she was unable to cope any longer and they separated in 1998. She thought that his attitude had changed and he felt like a failure. They were divorced on 17 September 1999.

32 The respondent's last operation for removal of bristles was in July 2000. The trial judge found that 167 bristles were removed from the respondent's body, with most of these being removed by Mr Clarke, the general surgeon. The length of the wires were in the range of 5 to 24 millimetres. During the course of his evidence Mr Clarke said "an injection needle is probably the same diameter as one of the wire bristles." More detailed expert evidence was also brought before the Court by experts for the respondent, William Apgar and Trevor Bastow, which suggested that the majority of the bristles removed from the respondent's body had a diameter of .41 mm.

33 The respondent's statement of claim in par 3 included various particulars in support of the assertion that the accident was caused by the appellant's negligence. Reference was made to an alleged failure to provide a suitable brush and to an alleged failure to instruct the respondent in regard to use of the brush. Reference was also made to a failure to provide proper protective clothing. In par 4 it was pleaded that as a result of the accident and subsequent treatment the respondent has suffered injuries and experienced various symptoms. He was required and will continue to require treatment and has been left with residual disabilities.

34 The injuries were described as penetration of foreign bodies in the form of metal wire bristles through his skin and becoming resident in various parts of his body. Particulars of treatment included reference to numerous operations to remove bristles from various parts of the respondent's body and to numerous skin grafts. Reference was also made to the treatment required in respect of his left ankle/foot. Particulars of his residual disabilities included reference to various difficulties of movement and a restricted range of movement in the left ankle/foot, left forearm and generally the joints in cold weather.

35 The claim included reference to matters relevant to an alleged loss of amenities and economic loss. A claim was also advanced for aggravated damages by reason of the appellant having alleged and continuing to allege in its defence that the respondent had engaged in the practice of self-mutilation for the purpose of supporting his claim.

36 The appellant by its defence denied the respondent's principal allegations and this put in issue the question of whether the accident occurred as alleged and whether it was caused by the negligence of the appellant. The appellant said further that if the respondent did suffer injuries, loss and damage they were caused wholly or in part by the respondent's own negligence.

37 Importantly, for the purposes of this appeal, the appellant said further (and conducted its defence at trial upon this basis) that the injuries and resultant treatment were self-inflicted by the respondent who deliberately inserted the bristles into his own body. The appellant said further that if bristles did enter the respondent's body on 29 July 1993 then only two bristles entered the respondent's right forearm. The two bristles in question were removed by Mr Clarke on the day of the incident and all other bristles subsequently removed from the respondent's body were deliberately inserted by the respondent into his own body.

38 I have already provided a brief outline of the evidence given by the respondent at the trial of the action in the course of his evidence in chief. He described the way in which he operated the brush provided by Mr Foskett and the "getting hit by sand" sensation he experienced during the comparatively brief period while he was operating the brush.

39 The balance of the respondent's evidence was largely concerned with the course of subsequent treatment and the removal of bristles from his body over a long period. He referred to his psychological difficulties and the break down of his marriage. He described being upset by the allegation of self-mutilation which first came to his attention at a later stage. It emerged during the course of his evidence that his employment with Delta Corporation was terminated in 1997. He continued to receive workers compensation payments to March 2000.

40 Under cross examination, the respondent conceded that at the time of the penetration by shards of wire on 8 November 1990 he felt pain in his leg. He conceded that there were other occasions on which wire bristles had struck him before 1993. He was then taken to 29 July 1993 and asked about his apparel on that day. He conceded that he was wearing ankle high boots, although the laces had not been done up to the top. As he used the grinder he felt things hitting him but thought it was just bits of concrete dust and residue. This being "all over, all over my body."

41 He noticed nothing was wrong with the wire brush until he turned it off and it was then he noticed that it only had a few bristles left. He felt no pain similar to that which he had experienced in 1990, although he did feel a pain in his right forearm. He did not notice any red marks or bleeding on his arm. He described the bristles removed from his body subsequently as being about 2 cm, although "some are smaller".

42 The cross examiner turned to the method of work and various answers were then provided to the cross examiner which in the course of legal argument on the appeal, were later characterised as admissions. It is therefore desirable to set out the relevant passage in its entirety:

"Do you agree with me that you've told - certainly in your affidavit that you filed and again you told Mr Apgar that you had your right foot outside the trough at all times?---Not at all times, but it says that in that affidavit.

That's what it says in the affidavit?---Yes.

Didn't you tell Mr Apgar that?---Yes.

So you've told your expert witness the same thing?---But I also said that I changed sides.

You didn't tell him that, did you?---I told Mr Apgar that, yes.

Okay. Would you agree with me that if the trough is almost knee height and you were wearing leather safety boots there's no way that you could get any metal shards into that foot?---I disagree with you because I have got bristles in that area.

Yes, we know that, but it couldn't have happened on that day, could it?---I don't know when it happened.

You don't know when it happened that you got the metal shards into your right foot?---No.

And you don't know when it happened that you got the metal shards into your left foot?---No.

You don't know when you got the metal shards into your left ankle?---No.

You don't know when you got them in your neck?---No.

You don't know when you got them in your face?---No.

Or your chest?---No.

And you don't even know how you got them in your back?---No."

43 The cross examiner then went on to pursue the allegation contained in the statement of defence that the respondent had been involved in a process of self-mutilation or self-inflicted injury. The cross examiner pressed the issue in the knowledge that evidence would be lead on the appellant's side from a Dr Townend that the bristles removed from the respondent's body were not consistent with an allegation that the bristles had been flung off a rotating wire brush on 29 July 1993, and immediately entered the respondent's body, because there were signs of subsequence interference with the bristles and they were not sufficient corroded. This exchange then occurred:

"Are you aware of a recent report from Dr Townend which suggests that these bristles have been interfered with since he saw them last?---No.

Dr Townend will say that since he originally saw them, some of these wires have been bent into J-shapes?---No.

Did you do that? ---No.

He will also say that, contrary to the condition they were in originally, they appear to have been stored wet which would I suggest hasten their corrosion. Did you do that?---No.

He will also say that they are shorter and parts have been broken off and the effect of that would be to disguise the pincer cuts on one end of the wires?---No.

Did you do any of that?---No.

Do you agree, seeing the wires, that they are shorter than when they were removed from your body?---They have all been different sizes; they all haven't been 2 Centimetres long, some are shorter than 2 centimetres. Some are about, well half a centimetre.

Did you cut these wires and put them into your body?---No.

Under the skin?---No.

Can you advance any reason why, if you say they came from the rotating brush, that all fully embedded themselves under your skin without your feeling anything?---I was going back to work after the accident.

Why didn't you feel these things go in, some of them 2 centimetres, at least 2 centimetres into your body. Can you tell me any explanation?---No.

Can you give me any explanation why they all went through your clothing, fully under the skin, and none only went part-way in?---No.

Can you tell me why you never saw any bleeding?---No.

---if you received those on one occasion?---No.

44 I pause to say that the respondent was not pressed as to whether he obtained bristles from other brushes held by his employer or from some other quarter for the purpose of self-mutilation. It emerges from the exchange that he did not make any concession in that regard.

45 The cross examiner continued to press the respondent as to the reliability of his account of the accident. This exchange then occurred:

"You have already agreed with me, save for the ones in your right forearm, you don't know when the others struck your body?---No. I don't know.

You are also aware are you not that - you have had x-rays from time to time?---Yes.

Those x-rays have not shown on that part of the body any wires and then subsequently a year or two later an x-ray in that part of the body has shown a number of wires. You are aware of that?---Yes.

Can you tell me why that has happened?---I returned back to work and I copped some more wires.

So you got those wires subsequent to the initial x-ray?---Yes.

Are you aware that the evidence that we intend to call is that the wires are of different gauges, different thicknesses, therefore they couldn't have come out of the one brush?---Yes.

Again, can you offer any explanation for that?---They use different types of wire brushes up there.

So they must have come on different occasions?---Yes."

46 The respondent's wife, who gave evidence as Michelle Lawrence, was cross examined about the defence allegation. She was asked whether she had ever seen her husband, Mark, inserting "these bristles" into himself. She replied: "Never". When asked what would have happened if she had seen that, she responded: "I'd have dobbed him in." She went on to say: "You don't rort the system to just to make yourself a lot better, no."

47 The respondent's case at trial was supported not only by the testimony of his former wife and fellow workers but by the evidence of various expert witnesses. Mr Clarke confirmed that he was a general surgeon who had been in specialist practice since 1992 and affirmed that in the course of treating the respondent by removing bristles from his body he had prepared six reports about the matter. In his report dated 11 May 1996 he noted that as at that date 135 bristles had been removed. They were spread throughout the respondent's body with the distribution being face 5, neck 10, chest including back 15, right arm including hand 17, left arm including hand 12, abdominal wall 15, right leg including foot 33 and left leg including foot 25.

48 In his 11 May 1996 report Mr Clarke went on to say that the bristles were lodged in deep and awkward positions including one which was within the lower eye lid. The greatest problem, however, had been with the complications of a wire bristle in the left ankle. It was infected at the time of removal on 30 December 1995. The wound required debridement on three further occasions and the inflammatory process proved to be such that it was necessary to obtain an opinion from a plastic and reconstructive surgeon.

"In January, 1995, extensive whole body investigations were undertaken in order to try and estimate how many foreign bodies this man had within him. These foreign bodies were not able to be identified on general scanning. Performing multiple x-rays up and down his body subjects him to high doses of radiation and it would be possible that the images that the foreign body could overlie bones and not be seen. There has been the possibility of performing a magnetic resonance imaging scan, however, this is dangerous in that if he has a deep foreign body, say in his back and he's placed face up with the magnet above him, then foreign bodies could be drawn deeper into his body and into more worrying parts of the body.

It is therefore not possible to estimate the number of bristles remaining in this man's body and as a result how many further operations he will require. It is impossible to estimate at this stage how many operations he will require on his left ankle by the plastic and reconstructive surgeons."

50 When Mr Clarke was cross examined as to the widespread location of the bristles and the fact that some of the bristles did not show up on the original X-ray taken in July 1993 he said that he had always assumed that this was due to the migration of foreign bodies and that some of them were located in areas where they did not show up on X-rays due to bony imposition. He agreed that it would be unusual for wire bristles to migrate to such an extent. He agreed that he had marked two entry points on the notes he made on 29 July 1993 when the respondent was complaining of two pieces in his arm. He agreed that he would expect to have seen more entry points. Under re-examination he said that at other times a red raised dot could be seen at the site where the foreign body was close to the surface.

51 Mr Allan, a plastic surgeon who gave evidence for the respondent, said he saw the respondent first on 2 May 1996 concerning a chronic ulcer that was located over his left ankle. He described a number of debridement procedures that were necessary because the dead tissue needed to be totally removed and each time what was thought to be the dead tissue subsequently became infected. He said that he operated on the respondent eight times and the Registrars operated on him under Mr Allan's supervision a further eight times. In the course of these operations he had removed a number of bristles including one from his right thigh and one from his right chest.

52 While speaking of the operation for the ulcer on the left leg, Mr Allan disagreed with the notion that the failure to heal would lead one to believe that it was due to self-mutilation. He accepted that any foreign bodies, such as bristles, embedded in the body can move. He was also of the view that where the bristle was overlying bone it could be difficult to distinguish what is normal bony architecture from a fine metal bristle. Under cross examination he said that if a person was showered with 170 pieces of bristle he would have expected the recipient to have felt a majority of them.

53 Professor Peter Burvill, a consultant psychiatrist gave evidence for the respondent. He confirmed an opinion provided in a written report that he did not believe the respondent showed any signs of malingering or exaggeration and there was no reason to consider that he had been self-mutilating. Under cross examination he disagreed with an opinion advanced by one of the appellant's witnesses, Dr Saunders, that the respondent's conduct and pattern of treatment subsequent to the accident was consistent with Munchausen's Syndrome, essentially because a person with such a syndrome does not usually present with the same complaint repeatedly. Professor Burvill referred to his treatment of the respondent for depression.

54 The respondent also adduced evidence from Mr Apgar, a forensic engineer. Mr Apgar expressed the view in a report dated 18 June 2001, after an examination of various evidentiary materials including a consideration of reports prepared by the appellant's experts, Dr Townend and Mr Price, that the wire brush used by the respondent "commenced to deteriorate almost immediately and within approximately 10 minutes had lost most of its wire fibres." He went on to say that the brush was likely to have held well over 1,000 wires. He was of the view that numerous wires entered the respondent's body and caused him injury. Factors which appear to have contributed to the accident were that the wire brush appeared to be rusty and this would have substantially weakened the wires and increased their tendency to break off in use.

55 Mr Apgar said that it was possible that the speed rating of the brush was inadequate for the angle grinder being used. This may have caused an over-speed condition which contributed to the tendency of the wires to break off with enough energy to penetrate the respondent's body in circumstances where he was not provided with adequate protective clothing. It was unlikely, in his view, that the respondent had cut wires and inserted them into his body as the vast majority of the wires had ends with brittle fractures. Many of the wires had one cut end but these appeared to be very uniform and were likely the result of the wire brush manufacturing process. In his view, cuts from other types of cutters would have had more variability in appearance.

56 Mr Apgar concluded his report by saying that the presence of a few wires with two cut ends and wires of other diameters and other materials could not be explained. It was possible loose short wires were trapped in the bundles of wires when the wire brush was manufactured. The larger wires and a certain stainless steal wire could have come from other wire brushes used by the respondent or by others working in close proximity to the respondent on other occasions.

57 The respondent also led evidence from a scientist, Mr Trevor Bastowe, as to the dimensions of bristles removed from the respondent's body (with a view to establishing that there was a substantial degree of uniformity in those dimensions) and from a metallurgist, Mr Peter Laczko, concerning the sensitivity of the type of wire in question to stress, corrosion, cracking and hydrogen enbrittlement if exposed to moisture. The evidence of these two witnesses was adduced, it seems, with a view to under-pinning the views expressed by Mr Apgar.

58 In summary, then, the respondent's case that the accident occurred as alleged was supported by testimony from the respondent himself that he was encouraged to use a brush showing some signs of rust. He felt a "hit by sand" sensation "like beach sand on a windy day" while using the brush and then noticed that the bristles on the brush were substantially depleted. Two bristles were removed from his arm on the day of the accident and many bristles were removed from other areas of his body thereafter without him having taken any step to insert them in his body.

59 Fellow workers including the appellant's acting foreman were able to affirm that bristles could penetrate parts of the body without the person being aware of it. The dimensions and condition of the brush were relevant to the drawing of an inference that the bristles entered his body when the brush began to disintegrate on the day of the accident. The respondent also relied upon the evidence of various experts in addressing the opposing allegation of self-mutilation, being a central constituent of the appellant's position on the pleadings and at trial. It is apparent from this summary that the respondent's credibility was an important but not the sole constituent of the case presented on his behalf at trial.

60 I have already noted that the appellant lead evidence at trial from its acting foreman, Mr Foskett concerning the brush handed to the respondent and the eventual disappearance of the object. In addition, the appellant lead evidence from Mr John Glancy, a radiologist, who reviewed the X-rays relating to the respondent. He testified in support of a view expressed in his written report dated 19 October 2000 to the effect that several parts of the respondent's anatomy had been radiographed more than once with differing results, that is to say, foreign bodies were easily seen on one occasion and not on the other. In the instances where the foreign body was present on the first examination and not the second he would feel free to assume that the object had been surgically removed, however, there were eight instances where a wire thread was visible on a latter radiograph that was not visible on an earlier one.

61 Mr Glancy said further that there was no reasonable radiological explanation for the late appearance of these objects. He added: "Perhaps one could opine that the wires had migrated through the tissues, but the possibility that so many had travelled such great distances is extremely unlikely." He accepted that it was possible to miss an end on shot of a wire on an X-ray.

62 Dr Paul Townend, a consulting engineer who gave evidence on behalf of the appellant, spoke of having examined metallic wire bristles which he understood were retrieved from the respondent's body. Having examined certain wires under a stereo-microscope he said that all were found to be plain carbon non-stainless steel and approximately 20 mm long. The majority of wire ends appeared to be cut and the degree of surface corrosion on the wires was variable. Given the difference in diameters between the wire samples provided it appeared as though the plain carbon steel wires extracted from the respondent were from both light duty and heavy duty brushes. Further, the degree of corrosion on the extracted wires did not correlate well with the length of time they were claimed to have been embedded in the respondent's body. The wires extracted in 1996 had abnormally little corrosion compared to the wires extracted in 1993 and 1994. Further, it was extremely improbable that the stainless steel wires extracted from the respondent came from the same brush as the plain carbon steel wires.

63 Dr Townend's view was that it was highly unlikely the 166 wire bristles extracted from the respondent's body over the four year period after the alleged accident entered his body as claimed in one incident in 1993 when they broke away from a wire cup brush. He said that he had "serious doubts the wire bristles broke off a wire cup brush as alleged" or that they had been in the respondent's body since the alleged incident in 1993.

64 Mr Price, a senior research fellow in the field of physics and engineering had been asked to provide an opinion in relation to penetration of steel wire bristles into human body tissue. He concluded that a small bristle wire travelling at a velocity of 40 metres per second impacting onto a body could penetrate into the body. He would not expect the wire to penetrate deeply and it would be close to the skin. The penetration of the bristles into a body would be influenced by clothing on the body because friction between the wire and the fibres would result in loss of energy. He did not believe that wires of length 20 mm would penetrate through clothing, and fully embed in a body.

65 Dr Saunders, a retired general surgeon who is now practising as a rehabilitation medical officer, presented a written report dated 7 December 1999 in which he expressed the view that it was beyond the realms of possibility that with more than 100 pieces of steel throughout his body they were not picked up more accurately by X-rays and CT scan. He was not convinced by Mr Clarke's explanation that the bristles might have been missed because they lie end on to the X-ray or overlie bones. In his view, a much more plausible explanation was that the presence of the bristles was the result of self-mutilation.

66 Dr Saunders went on to say that he "had no hesitation in making the diagnosis of Munchausen's Syndrome with self-mutilation." Under cross examination, he conceded that he had seen the respondent on one occasion only for an hour, although he had reviewed reports relating to the respondent. To him, Munchausen's Syndrome meant the person in question was self-inflicting or self-promoting an illness that did not exist. It is a condition characterised by habitual presentation for hospital treatment of an apparent acute physical illness. The patient gives plausible and dramatic history, all of which is false. He agreed that the syndrome was not common.

67 The learned trial Judge held that the respondent was injured on 29 July 1993 in the course of his employment when using an electric powered steel wire brush, cleaning concrete from vertical shutters when bristles broke off and entered the respondent's body. In reaching that conclusion he referred to the evidence of the respondent, Mr Kennedy and Mr Foskett and to the fact that Mr Kennedy had observed the brush and tried to obtain it. He said that there was no evidence to dispute the respondent's evidence as to how the alleged accident occurred and "I accept his evidence entirely." The trial Judge noted that there was evidence that metal bristles from wire brushes had penetrated the flesh of other employees before July 1993.

68 In the view of the learned trial Judge it was a clear case of negligence because there was a reasonably practical means of obviating the risk by providing protective garments, maintaining guards on the brushes and issuing appropriate instructions and warnings to the employees. The learned trial Judge noted that the appellant did not seek to justify its position on any of those matters, largely relying on its allegations that no bristles entered the respondent's body on the relevant date and that the respondent was self-mutilating. I note in passing, that this remained the position on the hearing of the appeal and the grounds of appeal do not bring such matters into issue. I note also that the learned trial Judge's findings that the respondent should not be held guilty of contributory negligence is not challenged in the appeal.

69 In the course of his judgment, the learned trial Judge addressed the appellant's contention that none of the bristles entered the respondent's body on 29 July 1993 or in the alternative that only two bristles entered his body on that date.

70 In addressing this issue, and the related issue of self-mutilation, the learned trial Judge undertook a thorough review of the evidence. He accepted that 167 bristles were removed from the respondent's body, with most of these being removed by Mr Clarke, the general surgeon. The learned trial Judge made a specific finding "on the balance of probabilities" that 86 per cent of the bristles entered the respondent's body on 29 July 1993. He found that the bristle to the ankle which caused the most serious damage entered the respondent's body on that day as alleged. His award of damages proceeds from the premise that the respondent is entitled to be compensated for the pain, treatment and loss of amenity referrable to the receipt and removal of the bristles. The judgment, in essence, amounts to a finding squarely in favour of the respondent's pleaded case that most of the bristles removed from his body subsequent to 29 July 1993 entered his body on that day as part of the events comprising the accident.

71 For present purposes, it is important to notice that in the course of his reasoning the learned trial Judge clearly gave considerable weight to matters of credibility. I have already noted his acceptance of the respondent's evidence "entirely" as to how the alleged accident occurred. The evidence of the respondent and Mr Kennedy as to the depletion of bristles on the brush after use was thought to be significant. The learned trial Judge went on to say that in his view the respondent's behaviour had been consistent throughout. "I had no problem in accepting him as a credible witness and clearly all of his treating medical specialists had no difficulty in treating him as a credible patient." He gave weight to the evidence of Mr Clarke, the general surgeon, who did not see anything unusual with the removal of the bristles and was always of the view that the bristles entered the respondent's body on 29 July 1993. The trial Judge preferred the evidence of Mr Clarke to that of Dr Glancy in regard to the question of whether the eight instances of the respondent's anatomy being radiographed more than once with differing results could be due to the possibility of the migration of foreign bodies.

72 The trial Judge was strongly critical of the evidence of Dr Saunders and the latter's diagnosis of Munchausen's Syndrome. He noted that Dr Saunders was not a psychiatrist and that his thesis concerning Munchausen's Syndrome was based upon scant information. The learned trial Judge's assessment of Dr Saunders' credibility was obviously affected by the cursory way in which the relevant opinion had been formed. The learned trial Judge said that he much preferred the evidence of the team of medical practitioners who assessed and treated the respondent including Professor Burvill.

73 In the course of assessing the technical evidence, the learned trial Judge was critical of the evidence given by Dr Townend, and especially that part of the evidence in which there was a suggestion that the wires or bristles to be used as evidence had been tampered with. The learned trial Judge noted that Dr Townend withdrew his allegation in that regard and had not reduced to writing his observations in December 1998 concerning the wires. He said that this evidence from Dr Townend "completely destroys his credibility as a witness generally" in that Dr Townend had accused an unknown person of tampering with the wires even though he had not taken measurements himself.

74 Having made a finding of fact that on the balance of probabilities at least 86 per cent of the bristles entered the respondent's body on 29 July 1993, including the bristle that caused the injury to the left ankle, the learned trial Judge concluded his appraisal of the technical evidence in these terms:

"The overwhelming number of wires are uniform in appearance. Any differences may be due to the manufacturing process. There has been no evidence led by the defendant with respect to the manufacturing process. The defendant alleges fraud in this case and the defendant has to lead strong evidence of fraud. Professor Burvill says that the plaintiff would have to be psychotic to be inserting these wires into himself. The plaintiff is not psychotic. His treating doctors thought him an attractive personality. By reason of the operations he descended into depression and was required to be treated on two occasions.

The clear evidence is that these wires do penetrate the flesh and treating surgeon Mr Clarke saw no evidence that he was inserting wires into himself and neither did his former wife.

The evidence indicates that some of the wires were asymptomatic for many months. The evidence also indicates that they can and do migrate. The evidence also indicates that they can be missed on x-rays.

The one fibre in his left ankle was asymptomatic to December 1995. I reject the defendant's submission that that could not have occurred because he was wearing boots. It would appear that it was at about the level of the boots. It was a serious and permanent disability.

In my view the plaintiff's behaviour has been consistent throughout. I had no problem in accepting him as a credible witness and clearly all of his treating specialists had no difficulty in treating him as a credible patient.

It is my finding that the defendant was negligent. It is my finding that the bristle to the ankle which caused the most serious damage entered the plaintiff's body on 29 July 1993 in the incident that he described."

75 It was against the background of these findings that the learned trial Judge proceeded to an assessment of damages.

76 I must now turn to the first of the various grounds of appeal. Ground one is in these terms:

"1. The learned trial Judge was wrong in finding that the incident alleged by the Respondent (Plaintiff) to have occurred on 29 July 1993 was the cause of the entry of the wire bristles into the Respondent's (Plaintiff's) body which bristles were removed in 1994 and subsequently (and in awarding the Respondent (Plaintiff) damages on that basis), and in so finding His Honour:

(a) failed to consider either properly or at all the legal principles related to causation;

(b) misapplied both the burden and standard of proof.

Particulars

(i) The Respondent's (Plaintiff's) admission that it was probable that many wire bristles had entered his body on subsequent occasions;

(ii) the overwhelming evidence to the effect it was improbable that the majority of the wire bristles surgically extracted from the Respondent (Plaintiff) entered his body on 29 July 1993;

(iii) there being no evidence that the majority of the wire bristles entered his body on that date."

77 This ground of appeal obliges me to begin by looking at some general principles concerning the burden and standard of proof in a civil action. I must also review some legal principles bearing upon the issue of causation.

78 A cause of action is simply the fact or combination of facts which give rise to a right to sue. In an action for negligence, it consists of the wrongful act or omission and the consequent damage. Do Carmo v Ford Excavations Pty Ltd [1984] HCA 17; (1984) 154 CLR 234 at 245. Thus, in order to support an action for damages for negligence the respondent must establish upon the balance of probabilities that he has been injured by the breach of a duty of care owed to him in the circumstances.

79 In the present case, I have already noted that the appellant seems to accept that a duty of care existed and that there was a failure to observe the standards of care required of the appellant. The controversy at trial was principally concerned with the question of whether the respondent was in fact injured as alleged in that bristles from the brush he was using entered his body. To put the issue another way: whether the appellant's failure to provide a suitable brush or safe system of work caused or brought about a situation whereby in the years that followed 86 per cent of the bristles subsequently removed from the respondent's body (on the Judge's finding), including the bristle responsible for the injury to the left ankle, entered his body on 29 July 1993.

80 The legal principles concerning burden and standard of proof are addressed in Cross on Evidence (Australian ed) at pars 7,001 to 9,055. The burden of proof in a civil case is the obligation of a party to meet the requirement of a rule of law that a fact in issue be proved upon the balance of probabilities. Put shortly, the plaintiff in a personal injuries action must satisfy the Court that it is reasonably safe in all circumstances of the case to act on the evidence before the Court, bearing in mind the consequences which will follow.

81 The possibility of a contrary finding does not prevent a finding reached on that standard from being appropriate. It is not enough for a plaintiff to fail that his account may not be correct. For example, in Goodwin v Nominal Defendant (1979) 54 ALJR 84 the plaintiff driver suffered head injuries and could not remember the relevant events. The surviving passenger was thought by the trial Judge to be unimpressive as a witness. The High Court held that the trial Judge had erred in concluding that the plaintiff must fail if there were valid reasons for taking the view that the hypothesis which supported his case may not be correct having regard to two alternative hypotheses adverse to the plaintiff's case.

"It was, we think, this process of analysis, involving initial assumptions and the postulating of what were three hypothetically probable explanations, together with the approach that the plaintiff must fail if there were valid reasons for taking the view that the hypothesis which supported his case may not be correct, which led to the conclusion that the plaintiff's claim should fail. Had the matter been approached by confining the inquiry to the question whether the plaintiff had satisfied the onus of establishing that it was more probable than not that the accident was caused by the negligence of the driver of an unidentified vehicle, his Honour must, we think, in view of his own careful assessment of the evidence as disclosed in his reasons for judgment, have found in favour of the plaintiff. His Honour did, of course advert to that question in the course of his judgment but seems never to have escaped the effect of the general approach which he adopted."

83 Any party who bears a legal burden of proof with respect to a fact will also bear an evidential burden with respect to that fact. The evidential burden has been defined as the obligation to show, if called upon to do so, that there is sufficient evidence to raise an issue as to the existence or non-existence of a fact in issue, due regard being had to the standard of proof demanded of the party under such obligation.

84 Cross notes at par 7,205 that the practice of speaking of the shifting of the burden of proof is quite inveterate among both Judges and writers. In essence, this is simply a reference to the tactical reality that where a party with the legal burden has discharged the associated evidentiary burden it then becomes prudent for the other party to adduce contrary evidence if possible. This is not really a shifting of any burden as the plaintiff who initially bears both the legal and evidential burden may fail to satisfy the legal burden, even if the other party calls no evidence.

85 The kind of problems that may arise are illustrated by Purkess v Crittenden [1965] HCA 34; (1965) 114 CLR 164. In that case there was evidence that previously to the accident the appellant was suffering from degenerative changes in the spine. The trial Judge assessed damages on the basis that her then present condition and resulting permanent disability were the result of the accident in which she was involved. A majority of the High Court affirmed the notion that the expression "burden of proof" has two distinct meanings. There is first, the burden of establishing a case, whether by preponderance of evidence, or beyond reasonable doubt and second, the burden of proof in the sense of introducing evidence. The burden of proof in the first sense is always stable; the burden of proof in the second sense may shift constantly, according as one scale of evidence or the other preponderates. Where a plaintiff has, by direct or circumstantial evidence, made out a prima facie case that incapacity has resulted from the defendant's negligence, it is not enough for the defendant merely to suggest the existence of a progressive pre-existing condition in the plaintiff or a relationship between any such condition and the plaintiff's present incapacity. Such an allegation must be the subject of evidence, being either substantive evidence in the defendant's case or evidence extracted by cross examination, which, if accepted, would establish with some reasonable measure of precision, what the pre-existing condition was and what its future effects were likely to be.

"In the present case the evidence accepted by the learned trial judge by no means established with any reasonable degree of precision the extent of the appellant's pre-existing affliction or what its future effects, apart from the result of the defendant's negligence, were likely to be. That being so we think it was proper for him to deal with the case on the basis that the defendant's negligence was the cause of the appellant's permanent disability and, accordingly, we propose to deal with this appeal on the same basis."

87 When a defendant pleads and introduces evidence pointing to criminal or fraudulent misconduct then it seems that special considerations will apply. This prompted the learned trial Judge in the present case to make the following observation at par 73:

"To allege that the plaintiff intentionally inflicted harm and then sued for damages is to allege fraud on the part of the plaintiff. The onus is on the defendant to prove fraud by clear and cogent evidence: Briginshaw v Briginshaw [1938] HCA 34; (1938) 60 CLR 336; Neat Holdings Pty Ltd v Karajan Holdings Pty Ltd [1992] HCA 66; (1992) 67 ALJR 170."

88 Against the background of earlier discussion concerning the burden of proof, a question arises as to whether it was appropriate to summarise the effect of the decided cases in that way. Cross on Evidence has this to say at par 9,050:

"When an issue falls for determination on the balance of probabilities and the determination depends on a choice between competing and mutually inconsistent allegations of fraudulent conduct, generalisations about the need for clear and cogent proof are likely to be at best unhelpful and at worse misleading. If such generalisations were to affect the proof required of the party bearing the onus of proving the issue, the issue would be determined not on the balance of probabilities but by an unbalanced standard. The most that can validly be said in such a case is that the trial Judge should be conscious of the gravity of the allegations made on both sides when reaching his or her conclusion. Ultimately, however, it remains incumbent upon the trial Judge to determine the issue by reference to the balance of probabilities."

89 The learned author goes on to note at par 9,055 that where satisfaction at the civil standard of proof depends on inference, there must be something more than mere conjecture, guesswork or surmise. That is, there must be more than conflicting inferences of equal degrees of probability so that the choice between them is a mere matter of conjecture. If there is, the test is as follows: the difference between the criminal standard of proof in its application to circumstantial evidence and the civil is that in the former the facts must be such as to exclude reasonable hypotheses consistent with innocence, while in the latter you need only circumstances raising a more probable inference in favour of what is alleged. Briginshaw v Briginshaw [1938] HCA 34; (1938) 60 CLR 336.

90 The proper approach in evaluating circumstantial evidence may be illustrated by reference to Transport Industries Insurance Co Ltd v Longmuir [1997] 1 VR 125. In that case the insured's house was damaged in a fire which had been deliberately lit. There was a large body of circumstantial evidence that the insured had lit the fire, including that he was on the property immediately before the fire started. The Court of Appeal held that the trial Judge erred in considering each item of circumstantial evidence in isolation from the others and seeking to determine whether the ultimate fact could be inferred from each such item of evidence. The proper approach was to consider the weight of the combination of proven facts and to determine whether the combined weight of those facts supported the inference, as a matter of probability.

91 Further, the trial Judge misdirected himself in the view of the Court of Appeal by applying the criminal standard of proof for circumstantial evidence. In civil cases, evidence is required only of circumstances raising a reasonable, definite and more probable inference of what is alleged. It is not necessary to exclude reasonable hypotheses consistent with the contrary of what is alleged. Winneke P noted at p 129 that where the trial Judge is asked to draw an inference that a party to civil proceedings has committed a criminal offence, the civil standard of proof still applies. However, it is necessary for the Court to bear steadily in mind that the seriousness of the allegations will affect the clarity of proof which is required with regard to the evidentiary facts from which the inference is to be drawn.

92 It appears, then, at this point in my review of the legal principles, that the respondent as plaintiff in the present case bore the legal burden of proof throughout. He was therefore obliged to satisfy the trial Judge upon the balance of probabilities that the events comprising the accident occurred as alleged and that his injuries in the form of the reception into his body of the bristles subsequently removed from his person happened on 29 July 1993. In the course of discharging the legal and evidential burden upon him it was open to him to rely upon inferences from material facts such as his own account of what happened, the experiences of fellow workers, and evidence concerning the state of the brush after the incident.

93 In the absence of any direct or eye-witness account of the respondent being struck by many bristles, it was open to the trial Judge to determine whether the combined weight of the facts and circumstances relied upon by the respondent supported the crucial inference, as a matter of probability, namely, that many bristles entered the respondent's body on the day in question. It was not necessary for the respondent to negate all alternative hypotheses as to how bristles finished up in his body in order to succeed, and he was not necessarily bound to fail simply because there was room for conjecture that the case presented on his behalf may not be correct.

94 It was open to the appellant, as it did, to adduce evidence in support of an opposing case of sufficient weight and precision to raise arguable issues in the form of alternative hypotheses that the bristles removed from the respondent's body did not enter his body on the day in question as alleged, (having entered his body accidentally on some other occasion) or, alternatively, that the bristles entered his body after the alleged accident date as a consequence of self-mutilation. Nonetheless, it did not necessarily follow that simply because the appellant had raised issues of the kind described in a persuasive manner the appellant had shifted the evidential burden back to the respondent with the result that the defence was bound to succeed. The task of the trial Judge at the end of the trial was to determine whether the respondent had proved his case upon the balance of probabilities, having regard to all the evidence. In his assessment of the appellant's allegation of self-mutilation, the trial Judge was obliged to determine the issue by reference to the balance of probabilities but, being conscious of the gravity of the allegation, he was entitled to proceed with caution.

95 When I turn to the question of causation I must begin by noting that such an issue often involves two rather distinct inquiries. The first involves the "factual" question whether the relation between the appellant's breach of duty and the respondent's injury is one of cause and effect in accordance with scientific or objective notions of physical sequence. If such a causal relation does not exist, that puts an end to the respondent's case: to impose liability for loss to which the appellant's conduct has not in fact contributed would be incompatible with the principle of individual responsibility on which the law of torts has been traditionally based. The second problem involves the question whether, or to what extent, the respondent should have to answer for the consequences which his misconduct has actually helped to produce. Fleming: "The Law of Torts (9th ed) 218; March v E&MH Stramare Pty Ltd [1991] HCA 12; (1991) 171 CLR 506 at 515.

96 In Bennett v Minister for Community Welfare [1992] HCA 27; (1992) 176 CLR 408 McHugh J described the rules concerning causation in these terms at p 428:

"Whether or not a causal connection exists between a breach of duty and any harm suffered by the person to whom the duty is owed is a question of fact to be decided on the balance of probabilities. The existence of the causal connection is to be determined in accordance with common sense notions of causation and not in accordance with any philosophical or scientific theory of causation or any modification or adaptation of such a theory for legal purposes. Moreover, the common law concept of common sense causation accepts that the chain of causation between breach and damage is broken for the purpose of attributing legal responsibility for that damage if there has been an intrusion of 'a new cause which disturbs the sequence of events, something which can be described as either unreasonable or extraneous or extrinsic'."

97 I digress briefly to observe that counsel for the respondent at the hearing of the appeal endorsed this view and went on to submit, having regard to recently decided cases such as Chappel v Hart (1998) 195 CLR 232, that the current state of the law can be summed up in this way: if a wrongful act or omission by a defendant creates or increases the risk of damage to the plaintiff and that risk eventuates, the defendant's conduct has materially contributed to that damage. In those circumstances the tribunal of fact is entitled to conclude that the act or omission caused the damage unless the defendant establishes that either the conduct complained of had no effect at all or the risk would have eventuated and resulted in the damage in any event. Thus, once a plaintiff demonstrates that a breach of duty had occurred that is closely followed by damage, a prima facie causal connection will be established. It is then for the defendant to show that the plaintiff should not recover damages. Henville v Walker [2001] HCA 52; (2001) 182 ALR 37 at par 148 per McHugh J.

98 Counsel for the respondent went on to submit that it was clear from the circumstances of the present case (and in any event it seemed to be accepted by the appellant) that there was a breach of relevant duty of care in that a hazard was known to exist and a safe system of work and protective clothing had not been provided. One should therefore move quickly to an inference that the appellant's conduct could be regarded as causing the injuries of which the respondent complained unless the appellant was able to show that the respondent should not recover damages.

99 It is immediately apparent, however, that such an approach begs the question, for the crucial inquiry in the present case is whether the injury complained of, namely, many bristles entering the respondent's body, actually happened on 29 July 1993 as alleged. The Court had to be satisfied that the risk had actually eventuated before it could embark upon an inquiry as to whether the party who had created the risk could be said to have caused the injury complained of. It seems from the way in which the case was conducted at trial that if this necessary constituent of the respondent's cause of action be established upon the balance of probabilities - that bristles actually entered the respondent's body on the day in question - then, consistently with the reasoning in decided cases such as Bennett (supra) and Chappel v Hart (supra), the necessary link between the creation of a risk of damage and the damage complained of can be inferred. However, the first and decisive issue in the circumstances of the present case is the factual question of whether the respondent actually suffered an injury of the kind alleged. The appellant contended at trial (and still contends) that it did not cause the respondent's injury in that an injury of the kind and to the extent alleged simply did not occur on the day in question.

100 I have already noted that the crucial findings of the trial Judge were adverse to the appellant's case. The trial Judge's finding at par 72 was that "on the balance of probabilities at least 86 per cent of the bristles entered the plaintiff's body on 29 July 1993. Typically that included the bristle that caused the injury to the left ankle." He went on to affirm (at par 89) that the defendant was negligent.

101 Against this background I must now return to the first ground of appeal. Ground one contains an assertion that the trial Judge failed to consider either properly or at all the legal principles related to causation. It is true that the judgment appealed from does not purport to review the principles and decided cases bearing upon causation and this might be thought to reflect a failure to consider the same. It follows from earlier discussion, however, that in the circumstances of the present case there was no need to embark upon a lengthy inquiry as to whether, or to what extent, the appellant should have to answer for the consequences of its alleged misconduct or as to other issues of a familiar kind concerning remoteness and foreseeability. The crucial question was of a factual kind as to whether the injury complained of actually happened on the day in question as alleged. It is quite clear that the trial Judge undertook a thorough review of the evidence bearing upon that factual issue and I am therefore not persuaded that he failed to consider either properly or at all the legal principles related to causation.

102 When I turn to the question of whether the trial Judge misapplied both the burden and standard of proof, I must take account of the particulars relied upon by the appellant. The appellant contends that the trial Judge failed to give proper weight to the respondent's admission that it was probable that many wire bristles had entered his body on subsequent occasions. Reference is also made to the "overwhelming evidence" to the effect it was improbable that the majority of wire bristles surgically extracted from the respondent entered his body on 29 July 1993 and that there was no evidence that the majority of wire bristles entered his body on that date.

103 I have already noted that the crucial finding of the trial Judge at par 72 that at least 86 per cent of the bristles entered the respondent's body on 29 July 1993 including the bristle that caused the injury to the left ankle purported to be made on "the balance of probabilities". It follows from earlier discussion that this was the appropriate standard of proof in regard to a personal injuries claim of this kind, and the trial Judge cannot be said to have fallen into error in that regard.

104 The main thrust of counsel's argument on the hearing of the appeal, as illustrated by the particulars, was that the evidence was not sufficient to support the trial Judge's finding in circumstances where the appellant had adduced persuasive evidence to the contrary. It follows from earlier discussion, however, that, notwithstanding such evidence, it remained open to the trial Judge to hold that the respondent had discharged his legal and evidential burden of proof having regard to the evidence considered as a whole.

105 The respondent as plaintiff was not obliged to negate all alternative hypothesis and the Court was not required to assume that the effect of the appellant's evidence was to "shift" the burden of proof so that the respondent was bound to fail unless the appellants' evidence was rebutted.

106 It is true that the respondent did not or was not able to say authoritatively that he saw or was conscious of many bristles entering his body on the day of the accident. However, as I have already noted, it was open to him by a combination of evidentiary materials to advance a case based upon an inference to be drawn from a combination of facts that the accident happened as alleged.

107 The particulars in support of this ground of appeal include reference to the respondent's so-called "admission" that it was probable that many wire bristles had entered his body on subsequent occasions. I drew attention to the relevant exchanges in cross examination at an earlier stage of this judgment. To my mind, it was essentially a matter for the trial Judge to resolve as to how this part of the respondent's testimony should be regarded, bearing in mind that the tenor of the respondent's evidence considered as a whole was to support his pleaded case. The respondent in his evidence in chief gave his account of what happened on the day in question and included reference to a stinging sensation like being struck by particles of sand on the beach on a windy day. It seems that he could say no more than that. It is important to remember that the trial Judge viewed him as a credible witness.

108 The cross examiner then proceeded, at this stage of the cross examination, to confront him with an alternative hypothesis that some or many of the bristles might have entered his body on another occasion. It sometimes happens under cross examination that a witness will agree what is being put to him without necessarily conceding the truth of the proposition, simply to avert an argument. To my mind, such a response is possible in a case of this kind where the respondent is only able to say that he felt a stinging sensation. In other words, all his answers to this part of the cross examination are consistent with him saying, in effect, "I have said all I can say about the incident and do not really know the exact answer to your questions". A response of this kind should not necessarily be characterised as a conclusive admission that the bristles did not enter his body as alleged. This was a matter for the trial Judge to assess having regard to the demeanour of the witness and the totality of the evidence.

109 This brings me to the role of the appeal Court. On an appeal it is necessary to distinguish between the finding of a specific fact and a finding of fact which is really an inference from facts specifically found or, as has sometimes been said, between the perception and evaluation of facts. Appellate courts will generally be reluctant to reject a finding of specific fact which may be founded on the credibility of the witness but in cases where the point in dispute is the proper inference to be drawn from proven facts, an appeal Court is generally in as good a position as the trial Judge to draw the necessary inference.

110 In Devries v Australian National Railways Commission (1993) 177 CLR 472 at 479 Brennan, Gaudron and McHugh JJ observed:

"More than once in recent years, this Court has pointed out that a finding of fact by a trial Judge, based on the credibility of a witness, is not to be set aside because an appellate court thinks that the probabilities of the case are against - even strongly against - that finding of fact. If the trial Judge's finding depends to any substantial degree on the credibility of the witness, the finding must stand unless it can be shown that the trial Judge 'has failed to use or has palpably misused his advantage' or has acted on evidence which was 'inconsistent with facts incontrovertibly established by the evidence' or which was 'glaringly improbable'."

111 That approach was recently approved in the High Court in Rosenberg v Percival [2001] HCA 18; (2001) 178 ALR 577 in which the trial Judge found that even if the patient in question had been warned of the slight possibility of complications, she would have proceeded with the surgery in any event. The High Court held that there was sufficient evidence to justify such a finding and the Full Court was in error in overturning the trial Judge's finding. The High Court was of the view that an appellate Court has a limited scope for review where a trial judge's finding of facts are based on an assessment of the credibility of a witness. A case must be exceptional to justify an appellate Court overturning a credibility based assessment of a trial Judge.

112 The approach in these cases was generally endorsed by the High Court in State Rail Authority of New South Wales v Earthline Constructions Pty Ltd (in liq) [1999] HCA 3; (1999) 160 ALR 588. However, that was a case in which notwithstanding the trial Judge's adverse view of a certain witness, the High Court was prepared to displace the findings of the trial Judge on the grounds that he had failed to give sufficient attention to crucial documentary evidence. The Court held also that while a finding of fraud in a civil case should not be lightly made, that does not entail application of the criminal standard of proof. In the case before the Court it was not the task of the appellant to exclude every reasonable hypothesis, but to establish its case on the balance of probabilities. The primary Judge had applied the wrong standard of proof.

113 The Earthline case is also significant for a detailed analysis by Kirby J on the basis upon which appellate courts are prepared to respect the advantages enjoyed by the trial Judge and to his or her findings affected by credibility. He observed that in many appeals a credibility finding will be far from conclusive of the proper outcome. He singled out various instances when credibility findings do not bar the appeal.

114 In some cases, his Honour observed, the evidence of the witness relates only to particular aspects of the dispute and leaves untouched other evidence which requires separate evaluation with no obstacle of a credibility finding. In such cases, to avoid appellate reversal, the trial Judge must demonstrate that such evaluation has occurred. It may be possible to show, by reference to incontrovertible facts or uncontested testimony, that although the trial Judge reached conclusions which were adverse to the credibility of an important, even crucial, witness, such conclusions are plainly wrong or were done on the basis of evidence which was wrongly admitted.

115 Further, the reasons of the trial Judge may demonstrate that the Judge took into account irrelevant considerations or has not properly weighed all of the relevant considerations. There is also the case where the credibility finding is so contrary to the extreme and overwhelming pressure resulting from the rest of the evidence, or is so glaringly improbable or contrary to the compelling inferences of the case, that it justifies and authorises appellate inference in the conclusion reached by the trial Judge.

116 It is apparent from earlier discussion that the respondent did not or was unable to say that he saw or felt many bristles from the brush enter his body on the day of the accident. He could speak only of feeling a sensation like being whipped by beach sand on a windy day. It follows that a central constituent of his case at trial was the requirement that the trial Judge draw an inference from the totality of the evidence that the injury occurred on that day as alleged. To that extent, at a first glance, it might seem from the decided cases that the Full Court is at liberty after a careful review of all the evidence to substitute its own determination for the central findings of the trial Judge if it is not satisfied upon the balance of probabilities that the accident occurred as alleged. However, as I have already indicated, it is apparent that in various significant respects the central inferential finding of the trial Judge in favour of the respondent's case at trial was dependent upon his findings as to credibility. He found the respondent to be a credible witness and it is apparent that his assessment as to the credibility of the respondent and his fellow workers played an important part in his evaluation of the evidence concerning the state of the brush after use and the experiences of those other employees who discovered bristles embedded in their bodies without being aware when they were hit.

117 The trial Judge also made important findings as to the credibility of certain of the expert witnesses as a consequence of which, it seems, he preferred the evidence of Mr Clarke for the respondent and viewed the evidence of the appellant's witnesses, Dr Townend and Dr Saunders, with considerable caution. There is force in the observation made by the learned trial Judge in the course of his judgment that nowhere during the course of the trial did the appellant or his witnesses suggest how the respondent could be deliberately inserting the bristles into his own body, bearing in mind, as Mr Clarke reported, that some of the bristles were lodged in deep and awkward places.

118 Against this background, I am of the view that the trial judge's finding depends to a substantial degree on the credibility of witnesses and must stand unless it can be shown that the trial judge has failed to use or has palpably misused his advantage of seeing the witnesses or has acted on evidence which was inconsistent with facts incontrovertibly established by the evidence or which was glaringly improbable.

119 When counsel for the appellant was pressed during the course of argument to identify evidence which could be described as inconsistent with facts incontrovertibly established or which was glaringly improbable or, alternatively, fell within considerations of the kind enunciated by Kirby J in the Earthline case, he singled out three matters in particular.

120 The first of these was the so-called "admission" by the respondent that the probabilities were that he received the bristles in his body on occasions subsequent to the accident. I have already indicated that, in my view, the evidence in question was somewhat equivocal and the importance to be attached to it would depend to a large extent on the trial Judge's assessment of the respondent's demeanour at that stage of the cross examination. I have difficulty in accepting that the answers provided to counsel should be regarded as firm and decisive "admissions" by the respondent sufficient to outweigh the other constituents of his case.

121 The second of the significant matters singled out by counsel was the X-ray evidence. It was said to be highly unlikely, having regard to the evidence of Dr Glancy, that fragments not detected by X-ray on one occasion should subsequently be found to be present. Again, I have difficulty in accepting that within the totality of evidence this aspect of the matter should be characterised as incontrovertible evidence. There was a difference of opinion between the experts as to whether X-rays would pick up fine wire bristles laid end on or in proximity to bone and in circumstances where a migration of bristles was a phenomenon known to medical practitioners. It is apparent from the judgment that the trial Judge undertook a thorough review of the evidence bearing upon this point and in the end expressed a preference for one body of expert opinion over another.

122 The third matter identified by counsel for the appellant as evidence demonstrating that the respondent's case was glaringly improbable or not consistent with incontrovertible evidence was the evidence of Dr Townend and Mr Apgar as to the state of the bristles. This was a reference to the hypothesis that certain of the wires removed from the respondent's body had been cut or were not corroded in a manner consistent with the respondent's case.

123 There was a difference of opinion between the expert witnesses as to this matter also, and as to that aspect of the matter the judgment of the trial Judge reflects a careful evaluation of the respective points of view. I remind myself again that a review of the evidence bearing upon this point has to be undertaken in the context of an allegation of fraudulent conduct on the part of the respondent and it was therefore legitimate for the trial Judge to evaluate the appellant's evidence with considerable caution having regard to the gravity of the allegation of self-mutilation. I am not persuaded that he fell into error as to this aspect of the matter.

124 When I draw together the various considerations bearing upon the first ground of appeal I am of the view that the appellant has not been able to demonstrate any error in regard to causation. The reasoning of the trial Judge is generally consistent with the legal principles I have referred to concerning the burden and standard of proof. It follows from my summary of those principles that it was open to him to make an inferential finding in favour of the respondent's case on the totality of the evidence notwithstanding that the appellant had identified with precision an arguable case to the contrary. I consider that the appellant's case on appeal amounts essentially to a challenge to findings based on credit and the preference for one body of expert opinion over another. To my mind, it does not fall within the exceptional class of case which permits appellate review of such findings. It follows that I am not prepared to allow the appeal on this ground.

125 Similar considerations apply when I turn to the second ground of appeal. This ground contains an assertion that the learned trial Judge was wrong in law and in fact in finding that the respondent had proved that the wire bristle removed from his left ankle had entered his body on 29 July 1993. For the reasons I have just given, I do not consider that there is a basis upon which an appellate Court should overturn the findings of the trial Judge.

126 Chappel v Hart (supra) is a persuasive authority to the effect that if a wrongful act or omission by a defendant creates or increases the risk of damage to the plaintiff and that risk eventuates, the defendant's conduct has materially contributed to that damage. In those circumstances a tribunal of fact is entitled to conclude that the act or omission caused the damage unless the defendant establishes that either the conduct complained of had no effect at all or the risk would have eventuated and resulted in the damage in any event. Thus, once the plaintiff demonstrates that a breach of duty has occurred, closely followed by damage, a prima facie causal connection will be established. It is then for the defendant to show that the plaintiff should not recover damages.

127 In the present case, the respondent as plaintiff presented compelling evidence that he experienced an injury on 29 July 1993 in the course of his employment as a consequence of the employer's unsafe system of work. Two bristles were removed from his forearm on that day and thus it can be said, having regard to my earlier review of the evidence, that at least to this extent an injury of a foreseeable kind eventuated. Against this background, and for the reasons I have previously given, I consider that it was open to the trial Judge to conclude that the bristle that caused the injury to the respondent's left ankle entered his body on that day.

128 The bristle in question was removed by Mr Clarke on 30 December 1995, being an occasion on which five bristles were removed from the respondent's body. The appellant's experts advanced various reasons why the wires in questions should be viewed with scepticism. However, the bristle removed from the left ankle fitted within the normal distribution curve and there was expert evidence to suggest that the wires came from the same brush.

129 The appellant contended also that the bristle could not have entered the left ankle on 29 July 1993 because the respondent was wearing boots at the time. However, the evidence in support of such a view was not conclusive. It seems the injury was at about the level of the boots. The respondent did not do the laces right to the top. The top of the unlaced boot was virtually in line with the injury to the left ankle and there was evidence from which it could be inferred that the respondent's left foot was inside the sleeper mould while he was carrying out the grinding and cleaning operation. For these reasons, as I have indicated, I do not consider there is a basis upon which an Appellate Court should overturn the findings of the trial Judge.

130 The third ground of appeal is that the learned trial Judge is wrong in law and in fact in rejecting the evidence of the expert radiologist Dr Glancy to the effect that the only logical explanation of the wire bristles not appearing on earlier X-rays of the respondent's anatomy but appearing on subsequent ones was that they must have entered the respondent's body subsequent to the initial X-ray in that:

(a) the respondent himself accepted that proposition as being a probable one;

(b) there was no expert radiological evidence to the contrary;

131 and further to the extent that his Honour accepted the evidence of the general surgeon Mr Clarke on this point (in preference to Dr Glancy) to the effect that some wire bristles may be overlooked on X-ray and others may migrate in the body is wrong in that his Honour has failed to consider either properly or at all the admissions of Mr Clarke that:

(i) it was improbable that so many wire bristles could have been missed on X-ray;

(ii) it was improbable that so many wire bristles could have migrated and for such a distance as they must have done;

(iii) it was probable that the logical explanation was that the wire bristles had entered the respondent's body on subsequent occasions;

(iv) that the literature upon which Mr Clarke relied indicated that such migrations over such distance was an extremely rare occurrence.

132 Again, my response to this ground of appeal is influenced by my earlier conclusions to the effect that it was open to the learned trial Judge to make a finding in favour of the respondent on the evidence before him, notwithstanding the presence of expert evidence weighing against the respondent's case. I noted earlier that the respondent was not obliged to negate all alternative hypotheses in order to succeed.

133 Counsel for the appellant submitted that the learned trial Judge dealt with the radiological evidence only when coming to examine the evidence as to the appellant's plea that the respondent had been self-mutilating. Counsel for the appellant contended that the learned trial Judge fell into error by confining himself in this way.

134 To my mind, such a submission reflects a rather formulaic view of the reasoning process. As I have already indicated in my review of the authorities, the task of the learned trial Judge was to determine whether the respondent had discharged his legal and evidential burden of proof having regard to the evidence considered as a whole. He was entitled to deal with the evidentiary issues adverted to in this ground of appeal in the context of the self-mutilation allegation because that was the central feature of the case put forward with a view to defeating the respondent's claim.

135 Mr Clarke did not adopt a dogmatic stance in regard to the likelihood of bristles migrating and this may have been a point in his favour when the time came for the learned trial Judge to assess his credibility. Accordingly, I am not persuaded that Mr Clarke's caution in the way in which he expressed his views should be characterised as an admission which arguably supports the views expressed by the appellant's expert witnesses. There was a controversy concerning the issue of migration. Ultimately, the trial Judge was obliged to resolve that controversy having regard to the evidence considered as a whole.

136 Put shortly, then, I am not persuaded that the findings of the trial Judge should be overturned having regard to this ground of appeal.

137 The fourth ground of appeal is that the learned trial Judge is wrong in fact and in law in rejecting the evidence of the appellant's expert metallurgist Dr Townend on the basis as expressed by his Honour that Dr Townend did not reduce to writing his observations on his examination of the wire bristles in December 1998 and on the basis that Dr Townend alleged that a scientist had tampered with the wire bristles; both such findings being entirely wrong on the evidence.

138 Further the evidence of Dr Townend that a large number of wire bristles:

(a) had two cut ends or had a worn end and a cut end and therefore could not have entered the respondent's body in July 1993 as alleged was evidence which was in effect agreed with by the respondent's expert Mr Apgar;

(b) meant that the wire bristles could not have entered the respondent's body on the date of the alleged accident on 29 July 1993;

(c) given that those wire bristles included the bristle which was removed from the respondent's left ankle means that on the balance of probabilities the said wire bristles must have entered the respondent's body on a time subsequent to the alleged negligence act of the appellant and therefore is not one in respect of which the appellant is liable in damages in this action;

139 The submissions of the appellant were to this effect. The learned trial Judge expressly rejected the evidence of Dr Townend on two bases being that he did not reduce to writing his observations made on his initial examination of wires in December 1998 and he formed an adverse view of Dr Townend's evidence in the light of his perception that Dr Townend was asserting the wires had been tampered with. This was an insufficient basis upon which to devalue or disregard Dr Townend's evidence. Dr Townend found that a lot of the wires alleged to have been removed from the respondent's body had bright ends with little or no evidence of corrosion indicating that they simply could not have been in the respondent's body from 29 July 1993 until removal. In addition, Dr Townend surmised that it was impossible for some of the wires to have come from the rotating wire brush as alleged because the wires had two cut ends, or alternatively a worn end and a cut end. This was allegedly confirmed in Mr Apgar's analysis.

140 In my view, it was open to the learned trial Judge to treat the evidence given by Dr Townend with caution for the reasons reflected in the judgment. He was also entitled to make an appraisal of Dr Townend's evidence after considering the evidence as a whole. The learned trial Judge observed that the overwhelming number of wire bristles were uniform in appearance and that differences might be due to the manufacturing process. In the absence of evidence as to the nature of the manufacturing process and the way in which wire bristles might be cut or come loose the Townend evidence, which was focused upon a number of specific wires, could not necessarily be regarded as conclusive.

141 I am not persuaded that the learned trial Judge fell into error in regard to the facts and matters the subject of this ground of appeal.

142 The appellant contends in regard to this ground of appeal that the finding by the learned trial Judge to the effect that an overwhelming number of wire bristles were uniform in appearance and that any differences may be due to manufacturing processes is conjecture and not based on the evidence. Further, his Honour's subsequent finding that there was an obligation on the appellant with respect to leading evidence as to the manufacturing process is misconceived. Any obligation in that regard remained at all times with the respondent.

143 The observations I made concerning the preceding grounds of appeal apply in regard to this issue. I am not persuaded that the learned trial Judge fell into error in regard to his application of the principles concerning burden of proof. He was obliged to resolve the controversy between the experts and there was a sufficient evidentiary basis for the learned trial Judge's verdict in favour of the respondent.

144 The sixth ground of appeal is that the learned trial Judge is wrong in fact and in law in awarding aggravated damages of $10,000 against the appellant on the basis of the manner in which the appellant conducted the claim and in particular by alleging that the respondent was self mutilating in that:

(a) the appellant's allegations of self mutilation were validly open on the evidence prior to trial given the respondent's insistence at all times prior to trial that all bristles entered his body on the one occasion and the lack of cogent evidence supporting that proposition;

(b) there was independent specialist medical evidence to that fact.

145 Paragraph 13 of the statement of claim included a claim for aggravated damages by reason of the defendant having alleged and continuing to allege in its defence that the plaintiff was and has for the purposes of supporting his claim engaged in the practice of self-mutilation. It was said that as a consequence of such an allegation the plaintiff had and continued to suffer extreme psychological stress, depression, anxiety and continuing psychological disorders.

146 The pleading goes on to allege that there was no reasonable basis upon which to found the allegation of self-mutilation and that as a consequence the plaintiff was entitled to additional damages.

147 The learned trial Judge concluded at par 100 of his written judgment that there was no justification for the defendant alleging that all of the plaintiff's injuries, treatment and symptoms were brought about as a result of self inflicted injuries. He went on to say that in his view, such a defence was not bona fide because it was not justified by the evidence available to the defendant. It amounted to an allegation of fraud in relation to the accident but without justification for such a plea. As I mentioned earlier, the learned trial Judge observed that nowhere during the course of the trial did the appellant suggest how the respondent could be deliberately inserting the bristles into his own body. The trial Judge went on to allow the plaintiff the sum of $10,000 by way of aggravated damages.

148 It is apparent from his Honour's judgment that he relied principally upon the reasoning of the High Court in Coyne v Citizen Finance Ltd [1991] HCA 10; (1991) 172 CLR 211. The plaintiff in that case obtained a jury verdict in his favour for defamation and was allowed a substantial award by way of general damages. Justice Toohey observed that persistence in a plea of justification may be relevant to the amount of compensatory damages awarded. An early withdrawal of the defamatory statement will ordinarily serve to reduce the harm suffered by the plaintiff; persistence in seeking to justify the statement may increase the scope of the publication and the effect on those who read it. However, compensation for continuing harm is a component of normal compensatory damages and in the absence at least of lack of bona fides, impropriety or unjustifiability, persistence in a plea of justification does not warrant an award of aggravated damages. Triggell v Pheeney [1951] HCA 23; (1951) 82 CLR 497 at 514 applied.

149 When that line of reasoning is applied to the circumstances of the present case it is clear that the learned trial Judge was of the view that there was a lack of bona fides on the part of the defendant in advancing the plea of self-mutilation. It amounted to an allegation of fraud in relation to the accident which, on his Honour's appraisal of the evidence, could not be sustained.

150 The appellant contended on appeal that the reasoning in Coyne v Citizen Finance (supra) was not truly applicable to the circumstances of the present case. The appellant had good and sufficient grounds for adopting the self-mutilation plea. The respondent had always maintained that all bristles entered his body on the one occasion but the likelihood of this was remote having regard to the evidence of the various expert witnesses. Further, the appellant had the report of an independent expert witness, Dr Saunders, an experienced medical practitioner, who had seen a number of cases of self-mutilation in the past, and his report advanced an opinion to the effect that this was a definite case of self-mutilation. There was other evidence to suggest that the respondent was malingering. In those circumstances, it could not be said that the stance adopted by the appellant at trial was without any justification or lacking bona fides.

151 The appellant did not seem to contend on appeal that aggravated damages cannot be awarded in negligence as a matter of principle. Its challenge to the ruling of the learned trial Judge was to the effect that the circumstances of the present case did not warrant the award made. Against this background, it becomes necessary to determine whether aggravated damages are capable of being awarded for negligence. If it be held that an award can be made, then it is necessary to identify the circumstances in which an award is appropriate. I am conscious that care must be exercised in translating the principles applied in a defamation case such as Coyne v Citizen Finance (supra) to the circumstances of the present case.

152 One finds a useful review of the decided cases concerning aggravated damages in Hunter Area Health Service v Marchlewski [2000] NSWCA 294; (2000) 51 NSWLR 268 commencing at par 94. The President of the New South Wales Court of Appeal, Justice Mason, drew attention to the distinction between aggravated and exemplary damages. Aggravated damages are given to compensate the plaintiff when the harm done to him by a wrongful act was aggravated by the manner in which the act was done. Exemplary damages, on the other hand, are intended to punish the defendant, and presumably to serve one or more of the objects of punishment, namely, moral retribution or deterrence. His Honour noted also that the issue of identifying those wrongs which attract an award of aggravated damages has received surprisingly little attention. Nonetheless, the case law reveals aggravated damages being awarded in a range of torts including defamation, intimidation, trespass to the person and malicious prosecution. He observed that it was difficult to discern any common thread linking the wrongs for which an award of aggravated damages has been made.

153 His Honour went on to say that Halsbury's Laws of Australia, volume 9 par 135-595 at 260, 338 states that the absence of any element of damage at large would generally exclude an award of aggravated damages in negligence or breach of contract. The principal authority in support of that proposition, his Honour noted, was the decision of the Court of Appeal in A B v South West Water Services Ltd [1993] QB 507 in which the Court struck out claims for both exemplary and aggravated damages, the latter being pleaded as based on indignation at the defendant's conduct following a negligently committed public nuisance. His Honour noted that in O'Reilly v Hausler (1987) 6 MVR 344 at 346 Dowsett J expressed serious doubt as to whether aggravated damages can be calculated with respect to personal injury without double compensation. See also Bergman v Haertsch [2000] NSWSC 528.

154 His Honour Justice Mason then went on to say this at par 110:

"The upshot is that I find no clear guidance in Australian case law on the broad question whether aggravated damages are capable of being awarded in a negligence action. In point of principle, I seriously doubt the need to engraft an award of aggravated damages upon a negligence claim. Compensatory damages would normally include damages for mental distress or injured feelings so long as they can be linked to the tort through existing principles of causation and remoteness of damage. To speak of aggravated damages as a separate component can only have the capacity to confuse and run the risk as to double compensation: cf Clerk & Lindsell on Torts 17th ed at 1498, O'Reilly (supra) at 346".

155 I have already noted that caution must be exercised in seeking to apply the reasoning of the High Court in a defamation case such as Coyne v Citizen Finance (supra) to a claim in negligence. It emerges from a consideration of the remarks made by Justice Mason in Hunter Area Health Service (supra) that there continues to be a degree of uncertainty as to whether an award of aggravated damages is available in respect of a claim in negligence. However, in my view, in the circumstances of the present case it is not necessary to express a final view about the broad issue concerning aggravated damages.

156 On any view of the matter, the decided cases suggest that if an award of damages is available in the case of a claim in negligence, it must be confined to those cases in which there has been some lack of bona fides or contumelious conduct on the part of the defendant. However, in the present case, I consider that there was sufficient ambiguity in the circumstances surrounding the accident and in the subsequent events to justify the appellant's plea of self-mutilation.

157 Counsel for the respondent submitted that the onus lay on the appellant to substantiate its allegation for fraud. That required clear and cogent evidence which was not provided. Counsel submitted that the only medical witness who expressed the view that the respondent was a self-mutilator was Mr Saunders who purported to proffer a psychiatric opinion which he was found to be unqualified to express. Further, as the learned trial Judge correctly noted in his judgment, nowhere during the course of the trial did the appellant suggest how the respondent could be deliberately inserting the bristles into his own body.

158 It follows from earlier discussion that, in my view, it was open to the learned trial Judge on the evidence before him to find in favour of the plaintiff and to dismiss the allegation of self-mutilation relied upon by the appellant. However, such a view of the evidence does not necessarily bring with it a finding that the appellant acted in a wrongful or contumelious manner in requiring the plaintiff to satisfy the Court that there was no element of self-mutilation involved. The opinion of Mr Saunders did not stand in isolation. To my mind, there was sufficient ambiguity in the circumstances of the accident and sufficient merit in the expert evidence relied upon by the appellant to justify the appellant's stance at trial.

159 Accordingly, I consider that the appellant is entitled to succeed on this ground with the result that the award of aggravated damages of $10,000 should be set aside.

160 The seventh ground of appeal is that the learned trial Judge is wrong in law and in fact in awarding the respondent any amount at all for past loss of earning capacity or future loss of earning capacity, there being no evidence that the respondent suffered any such loss arising from the incident on 23 July 1993.

161 In regard to this ground of appeal the appellant noted that the learned trial Judge awarded the respondent $229,566.75 for past loss of earning capacity and $292,125 for future loss of earning capacity. Counsel drew attention to those passages in the judgment from which it appears that after the incident on 29 July 1993 the respondent was off work for two days and then returned to full employment until he commenced having many periods of hospitalisation in 1995. He ceased work on 23 February 1996 and was ultimately terminated from his employment on 7 September 1997.

162 The appellant said that the respondent's action was brought under the former provisions of s 93D of the Workers Compensation and Rehabilitation Act which required him to show a future pecuniary loss which at the date of trial stood in the amount of $126,128. It was therefore necessary for him to plead and prove future pecuniary loss incurred by him as a consequence of the injuries suffered on the precise date as pleaded. Even if he suffered further injuries in the course of his employment which resulted in him having bristles removed on subsequent dates, his claim must necessarily fail unless he can prove that all his bristle injuries, and in particular the one in his left ankle, arose on that date.

163 Counsel for the appellant went on to argue that for the reasons advanced in the earlier grounds of appeal the respondent, not having made out a sufficient case that the accident and consequential injuries occurred as alleged, should not be awarded any amount at all for economic loss or for damages at all.

164 There is now no need for me to respond to this ground of appeal at length. It follows from my observations in response to the earlier grounds of appeal that, in my view, the appellant has failed to demonstrate that the learned trial Judge was in error in holding that the accident and injuries occurred as alleged. The corollary is that the learned trial Judge had a sufficient basis in fact for making an assessment for past loss of earning capacity and for future loss of earning capacity. I will deal with the sufficiency of his reasoning in regard to the future loss of earning capacity in the context of the issue raised by the respondent's cross appeal and notice of contention.

165 The appeal book contained a notice of cross appeal dated 7 November 2001 in which notice was given that the respondent intended upon the hearing of the appeal to contend that the judgment should be varied by setting aside the award to the respondent of the sum of $725,184.60 general damages and substituting a higher figure for such damages in such amount as the Court considers fit. By his notice of contention the respondent sought to uphold the figure allowed to him even if the appellant succeeded in regard to the issue of aggravated damages.

166 The grounds upon which the respondent relied for the cross appeal were, first, that the learned trial Judge allowed the respondent's claim for future economic loss but erroneously quantified that loss at the sum of $292,125 as a component in the overall award of damages; second, that the learned trial Judge correctly assessed the value of the respondent's future earning capacity at the sum of $584,250 but then reduced that excessively by a discount of 50 per cent allegedly for retained earning capacity without making any or any sufficient finding as to the nature and extent of the respondent's retained earning capacity or otherwise justifying what is a manifestly excessive discount.

167 The reasoning of the learned trial Judge is reflected at par 117 to par 121 of the judgment. His Honour noted that the respondent claimed damages for future economic loss at the rate of $750 per week on the basis that he was presently aged 30 years and would, under normal circumstances, have worked until the age of 65 years. Utilising the 6 per cent tables the appropriate calculation produced a figure of $584,250.

168 The Judge was of the view that the rate claimed was reasonable and he accepted that the respondent would have continued to work to the age of 65 years upon the basis that he appeared to be a conscientious employee. He then went on to hold that if he discounted the figure thus produced by 50 per cent for retained earning capacity, that would be a reasonable sum to allow the respondent. It was upon this basis that the sum of $292,125 was allowed by way of future economic loss.

169 Counsel for the appellant contended that the learned Judge was relying upon reasoning of the kind reflected in Malec v J C Hutton Pty Ltd [1990] HCA 20; (1990) 169 CLR 638. In that case Deane J, Gaudron J and McHugh J observed that in assessing damages where questions arise as to the future or hypothetical effect of physical injury or degeneration, the degree of probability of the occurrence of associated future or hypothetic events will be evaluated by the Court (except in the extreme cases of mere speculation or a practical certainty). Where proof is necessarily unattainable, the Court assesses the degree of probability that an event would have occurred, or might occur, and adjusts its award of damages to reflect the degree of probability, leading to an increase or decrease of the amount of damages otherwise to be awarded. The approach is the same whether it is alleged that the event would have occurred before, or might occur after, the assessment of damages takes place.

170 It is true that Brennan and Dawson JJ expressed the view that it is undesirable that damages be assessed on the footing of an evaluation expressed as a percentage, or that "probability" be used to describe a minimal possibility. However, it is clear from the decided cases that ultimately the trial Judge must make his best assessment upon the basis of the evidentiary materials available to him.

171 Counsel for the appellant submitted that in circumstances where the learned trial Judge had limited information as to the nature and extent of the future incapacity, bearing in mind that the appellant had not thought about work for the past four years due to the toll taken by his ongoing treatment and the psychological side effects, the only course open to the trial Judge in practical terms was to evaluate the position by making a percentage reduction. The reduction of 50 per cent was about right in the circumstances.

172 In regard to the cross appeal and the issue raised by the respondent's notice of contention, counsel for the respondent acknowledged that the critical enquiry on appeal from awards for personal injury is whether the overall assessment of damages is reasonable in all the circumstances of the case. These principles are particularly pertinent in a case like this where the damages award is made up of several components, the majority of which are based on discretionary considerations. In these circumstances, there was considerable room for individual choice in regard to a multitude of factors. State Government Insurance Commission v Hitchcock, unreported; FCt SCt of WA; Library No 970089; 11 March 1997.

173 He referred also to Calder v Boyne Smelters Ltd [1991] 1 Qd R 325 which suggests that a judgment should be characterised as a global award to compensate for all the detriment suffered and it is made only once by the payment of one lump sum. Thus, although an assessing Judge may allocate particular sums to particular heads of detriment and express them in his reasons, the judgment does not constitute a series of awards under particular heads, nor does it constitute a mere aggregation of the sums separately allocated. It is the allocation of particular sums which discloses the process of reasoning which leads to the exercise of judicial discretion which is given effect to in the final award in the form of a single lump sum. What is appealed against is the total sum awarded, that is to say, the discretionary judgment as reflected in the lump sum award. Whether the appeal is successful depends upon the answer to one ultimate question. That question is whether the appellant has demonstrated error which has lead to an assessment which is outside the limits of what a sound discretionary judgment could reasonably adopt.

174 Counsel for the respondent referred also to Gamser v Nominal Defendant [1977] HCA 7; (1977) 136 CLR 145 and to Lloyd v Faraone [1989] WAR 154. Counsel asserted that the proper approach is to look at the total sum awarded as general damages and at all the circumstances, the pain and suffering, past, present and future, the physical disabilities, the medical and psychological problems which are inevitable for the future, the effect on earning capacity and the kinds of additional costs which the appellant will necessarily incur, and to ask oneself whether the sum awarded is wholly disproportionate to the circumstances.

175 Counsel for the respondent sought to apply these cases principally to the issue raised by the notice of contention. However, in my view, these cases must also be kept in mind in regard to the issue raised by the cross appeal. As I have already indicated, the stance of the respondent in regard to the cross appeal was that in the absence of specific findings by the learned trial Judge as to the nature and extent of the appellant's retained earning capacity, the large reduction of 50 per cent employed by the trial Judge could not be justified, and manifested error. It followed that the amount of the reduction should be reviewed by the Full Court or the matter sent back for a further assessment directed to that issue. He said that the large discount to reflect retained earning capacity was clearly erroneous.

176 There is considerable force in the respondent's submission when one has regard to a recent decision of the Full Court in this State, namely Villasevil v Pickering [2001] WASCA 143; (2001) 24 WAR 167. The plaintiff in that case sustained a serious fracture to her right leg when she was run over while sitting on the road verge outside her home. The learned trial Judge's calculations in that case did not contain allowance for a retained earning capacity, although they did include a 75 per cent reduction of the amount otherwise allowed for loss of future earning capacity, being a discount for "vicissitudes of life".

177 The Full Court in that case took it from the trial Judge's reasoning that the plaintiff had been left with no useful earning capacity although his determination in that regard was not entirely clear. The reasoning of the Full Court suggested that the proper course is to make a finding as to the nature and extent of the incapacity before determining the plaintiff's prospective earnings as a lump sum by the use of the appropriate multiplier. It is then, once the lump sum is determined, that a reduction of about 10 to 15 per cent (being the usual percentage) might be made as a discount for the vicissitudes of life.

178 When I translate the reasoning in Villasevil (supra) to the present case I am immediately conscious that in this case, unlike Villasevil, the trial Judge held that there was a retained earning capacity. There is force in the appellant's submissions that there was limited, and somewhat ambiguous information before the trial Judge bearing upon this point. It therefore seems to me that to attempt to quantify the prospective loss of earnings as a lump sum in the special circumstances of this case by the means outlined in Villasevil and similar cases would be a speculative venture. Ultimately, the trial Judge was obliged to do the best he could by discounting the lump sum by an appropriate percentage, bearing in mind the decided cases I mentioned earlier concerning the importance of the global award.

179 It is material to note in the circumstances of the present case, that the respondent was not disabled entirely. He, himself, seemed to accept that he had some earning capacity and that it would be necessary to undertake some re-education. The learned trial Judge was confronted with a difficult situation in making his assessment because the psychological consequences of the unusual nature of the injury and the long course of subsequent events, made it difficult to arrive at a clear view as to the nature of the respondent's employment prospects. In these circumstances, and having regard to Malec v J C Hutton Pty Ltd (supra), I am not persuaded that the Judge was in error in assessing the value of the respondent's future earning capacity at the sum of $584,250 and then reducing that amount by a discount of 50 per cent for retained earning capacity. To my mind, the discounted figure may also be taken as making suitable provision of about 15 per cent for the vicissitudes of life.

180 I must now turn to the issue raised by the respondent's notice of contention.

181 At the hearing of the appeal counsel for the respondent obtained leave to hand up and be heard in relation to a notice of contention. The notice of contention was to this effect: in the event that the Full Court upholds the sixth ground of appeal (concerning the award of $10,000 to the respondent by way of aggravated damages) the overall assessment of damages in the sum of $725,184.60 is correct and reasonable in all the circumstances of the particular case and/or is not manifestly erroneous or outside the boundaries of sound discretionary judgment.

182 Counsel for the respondent submitted that it is the learned trial Judge's total assessment which must be appraised on appeal. That total assessment must be shown to be unreasonable if it is to be disturbed. In the circumstances of the present case, he contended, the overall assessment of damages in the sum of $725,184.60 could not be characterised as manifestly excessive by reference to the application of sound discretionary judgment. This would be so irrespective of whether the award of aggravated damages was set aside.

183 It follows from my earlier observations that I consider the appeal should succeed in regard to the sixth ground of appeal and that the award of $10,000 to the respondent by way of aggravated damages should be set aside. It follows that consideration must therefore be given to the issue raised by the notice of contention and to the submission made by counsel for the respondent.

184 As I have already indicated in regard to the cross appeal, I am not persuaded that the discount applied by the learned trial Judge was in error or that the assessment of damages for future economic loss was wrong. In my view, however, having set aside the award of aggravated damages for the reasons previously given, it would be wrong in principle to allow the amount in question to be notionally reinstated by allocating to the respondent as part of the overall award of damages the sum characterised previously as aggravated damages. Accordingly, I would dismiss the issue raised by the respondent's notice of contention.

185 The appeal will be dismissed save for the sixth ground of appeal concerning the award of $10,000 for aggravated damages. The appeal will be allowed as to that ground. It follows that the award in the Court below will be varied so that the amount for which judgment is to be entered is the sum of $715,184.60. The cross appeal will be dismissed.