Reported Decision : (2000) 19 NSWCCR 302 New South Wales Court of Appeal CITATION : Colliar v Bulley & Anor [2000] NSWCA 1 FILE NUMBER(S) : CA 40505/98 HEARING DATE(S) : 13 September 1999 JUDGMENT DATE : 7 February 2000 Mr & Mrs R Colliar t/as Mid North Coast Mushrooms (Appellant) v PARTIES : Marilyn Dawn Bulley (First Respondent) Yancu Pty Limited t/as Riverview Motor Inn (Second Respondent) JUDGMENT OF : Priestley JA at 1; Meagher JA at 58; Davies AJA at 59 LOWER COURT JURISDICTION : Compensation Court LOWER COURT 18667/96 FILE NUMBER(S) : LOWER COURT Truss DCJ JUDICIAL OFFICER : A: P Deakin QC, L Stone COUNSEL : R1: M Sneddon (Submitting) R2: M Cranitch SC, K Sibley A: Hickson Wisewoulds SOLICITORS : R1: Walker Smith Solicitors R2: Sparke Helmore Solicitors CATCHWORDS : Workers Compensation - whether s16 of Workers Compensation Act 1987 applied - whether worker's employment was a substantial contributing factor to the aggravation, acceleration, exacerbation or deterioration of his disease of osteoarthritis - whether a frank injury may fall within s16 - what is an injury. LEGISLATION CITED : Workers Compensation Act 1987, ss4,9,16,22 Compensation Court Act 1984, s32 Zickar v MGH Plastic Industries Pty Ltd (1996) 187 CLR 310 Willis v Moulded Products (Aust) Ltd [1951] VLR 58 MLC Insurance Ltd v Pinto (1994) 10 NSWCCR 101 Yates Bros (Stratford) Pty Ltd v Neil [1999] NSWCA 108 Australian Conveyor Engineering Pty Ltd v Mecha Engineering Pty Ltd (1998) 45 NSWLR 606 CASES CITED: Darling Island Stevedoring & Lighterage Co Ltd v Hankinson (1967) 117 CLR 19 O'Neill v Lumbey (1987) 11 NSWLR 640 Accident Compensation Commission v McIntosh [1991] 2 VR 253 Insurers Guarantee Fund NEM-General Insurance Ltd v GIO General Ltd (1994) 33 NSWLR 247 Sutherland Shire Council v Baltica General Insurance Co Ltd (1996) 39 NSWLR 87 QBE Insurance Ltd v Switzerland Insurance Workers Compensation (NSW) Ltd (1996) 70 ALJR 281 DECISION : Appeal allowed. See para 80. IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 40505/98 CC 18667/96 PRIESTLEY JA MEAGHER JA DAVIES AJA MONDAY 7 FEBRUARY 2000 MR & MRS R COLLIAR t/as MID NORTH COAST MUSHROOMS v Marilyn Dawn BULLEY & ANOR JUDGMENT 1 PRIESTLEY JA: Pursuant to s 32 of the Compensation Court Act in the form it had taken before the worker in this case had commenced her proceedings (see Act No 89 of 1995, Schedule 3 Pars [13] and [29]), this appeal is one in which the appellants' only right of appeal is one which limits their grounds to points of law. The appeal was conducted for the appellants on this basis. 2 Although the notice of appeal contained a number of grounds, in the appellants' written submissions the grounds were reduced to one: that the trial judge erred in law in failing to find that an injury the worker suffered on 6 October 1995 was a progressive disease injury (as I call it as I explain later) and not a frank injury, as her Honour found. This ground involved the assertion that as a matter of law s 16 of the Workers Compensation Act 1987 (the Act) applied to the alleged progressive disease injury. 3 This question of law can only be properly understood by reference to ss 4 and 16 of the Act as it stood before it was very significantly amended by Act No 120 of 1996, so before coming to the facts of the case I will seek to describe briefly the meaning and relationship of those sections, insofar as they are relevant to the appeal. 4 The statutory background. Section 4 was of basic importance to the Act because it defined (and limited) the width of the term " injury " in the Act's primary provision entitling a worker to compensation. This was s 9 which was as follows: "(1) A worker who has received an injury (and, in the case of the death of the worker, his or her dependants) shall receive compensation from the worker's employer in accordance with this Act. (2) Compensation is payable whether the injury was received by the worker at or away from the worker's place of employment." 5 Section 4 (which, in the earliest form of the Workers Compensation Act 1926, had appeared in somewhat different form as part of the compensation - entitling section itself) was as follows: "4. In this Act: 'injury' (a) means personal injury arising out of or in the course of employment; (b) includes: (i) a disease which is contracted by a worker in the course of employment and to which the employment was a contributing factor; and (ii) the aggravation, acceleration, exacerbation or deterioration of any disease, where the employment was a contributing factor to the aggravation, acceleration, exacerbation or deterioration; and (c) does not include (except in the case of a worker employed in or about a mine to which the Coal Mines Regulation Act 1982 applies) a dust disease, as defined by the Workers' Compensation (Dust Diseases) Act 1942, or the aggravation, acceleration, exacerbation or deterioration of a dust disease, as so defined." 6 In Zickar v MGH Plastic Industries Pty Ltd (1995) 187 CLR 310 the High Court dealt with the question whether pars (a) and (b) of the definition were mutually exclusive. In their joint reasons Toohey, McHugh and Gummow JJ described the question of construction as follows: " The appellant says that if there is personal injury as described in par (a) the inquiry need proceed no further . If there is not personal injury as described he must rely on par (b) in which case the question of employment as a contributing factor has to be considered. But, he says, the two paragraphs are not mutually exclusive, nor is par (b) to be read as limiting what otherwise would be within the reach of par (a); they simply provide two bases upon which a claim may succeed. The respondent answers that this approach involves an unwarranted fragmentation of the definition of injury. The definition must be read as a whole and if the worker has contracted a disease (and an aneurism is a disease) the worker must establish employment as a contributing factor." (at 328, my emphasis) 7 They first considered the construction question simply by reference to the text of the section itself. They said: " The layout of the definition in s 4, which differs from its predecessor, certainly suggests that the first inquiry is whether there has been personal injury , a term which itself is not defined and which therefore must be understood according to ordinary concepts. For present purposes, par (c) can be put to one side. That exclusion is explained by the existence of other legislation dealing expressly with dust disease. That par (a) begins with the word 'means' and par (b) begins with the word 'includes', suggests that par (b) is designed to give an extended meaning to 'injury' by going beyond personal injury and to a disease in the circumstances prescribed: Dilworth v Commissioner of Stamps [1899] AC 99 at 105-6. In particular, there is no rule of construction which requires inclusive words to be read as exclusive of any elements which otherwise fall within the meaning of the word or expression being defined: Favelle Mort Ltd v Murray (1976) 133 CLR 580 at 588-589, per Barwick CJ, and no occasion with this legislation for the imposition of such a construction." (at 329-330, my emphasis) 8 They then considered previous authorities which the respondent employer had submitted stood in the way of this conclusion. They explained why in their opinion these authorities did not have the effect contended for. In the course of this discussion they held that Mr Zickar had, as s 9 said, "received" an injury within the meaning of par (a) of the "injury" definition and also recognised that the worker was suffering from an autogenous disease which fell within par (b). They said: " But the present case is not one of an autogenous disease. Or, to put it more accurately, it is not an autogenous disease upon which the appellant relies. It may be accepted that the aneurism was an autogenous disease but the appellant's claim to personal injury within par (a) is based on the rupture which occurred . From Dr Stening's evidence, it is clear that the rupture of the aneurism was not inevitable and further that the rupture may have been minor, allowing the appellant, after treatment, to return to his previous occupation. If there was no rupture there would be no event answering the description of personal injury and the appellant would be driven to rely upon par (b) of the definition. But there was such an event and the presence of a disease does not preclude reliance upon that event as personal injury ." (at 334, my emphasis) 9 In confirmation of their conclusion they then referred to previous decisions of the High Court, Darling Island Stevedoring & Lighterage Co Ltd v Hankinson (1967) 117 CLR 19, this court, O'Neill v Lumbey (1987) 11 NSWLR 640, and the Appeal Division of the Supreme Court of Victoria Accident Compensation Commission v McIntosh [1991] 2 VR 253, which were in their view all to the same effect. In the Victorian decision, Murphy J, who wrote the principal opinion, referred to the fact that the equivalent of par (a) had been the definition of injury long before the inclusion of the reference to disease ((1991) 2 VR at 263) and continued: "It is a remarkable development that today it is being suggested that in an Act which has consistently demonstrated a widening of cover to a worker, (being in the nature of social insurance or security) the inclusion in the definition of 'injury' of references to disease contributed to by the employment has prompted argument that mishaps, formerly accepted without debate to be 'injury', are no longer to be so considered, but are rather to be characterised as the very disease to which they are due, and excluded, unless work contributes to them." (at 264) 10 Although from time to time amendments to the Act reduce workers' cover in some ways, as for instance Act No 126 of 1996, there had been no amendments by the time of this case affecting the accuracy of Murphy J's statement, at least about sections such as s 4. 11 Kirby J, the other member of the High Court majority in Zickar, thought, unlike Toohey, McHugh and Gummow JJ, that earlier authority was contrary to their conclusion, but he was further of opinion that that authority was wrong and should no longer be followed. His view of the way s 4 worked was the same as the other three of the majority: "The structure of s 4 of the 1987 Act makes plain, by the design of the section, what was, in any case, previously clear enough. To add to a definition a special additional ground for securing benefits and to provide that the definition 'includes' those grounds does not, on ordinary principles of construction, subtract from the operation of the primary definition according to its terms." (at 346) 12 Upon this basis, although he thought that until the earlier authority was overruled the dichotomy claimed by the respondent had existed, Kirby J reached the same conclusion as the others of the majority. Under the subheading Conclusion and orders, he said, in part, "No longer is there a dichotomy between 'personal injury' in its full sense and 'disease injury' within the additional part of the definition. A worker is entitled to succeed if he or she can bring a claim within either head of recovery. Logically, the first question to ask, including in cases which might otherwise be classified as manifestations of a 'disease', is whether, notwithstanding that manifestation, the case falls within the primary definition of 'injury' as a 'personal injury arising out of or in the course of employment'. In that context, the word 'injury' should not be given a narrow meaning. It should have an ample application, in no way read down because Parliament, additionally, has provided a separate head of recovery for cases of work-related diseases." (at 351-2, my emphasis) 13 The main point of the appellant in the present appeal depends upon a submission about an "injury" allegedly within the inclusive definition of s 4(b)(ii) which for the sake of shortness I call a progressive disease injury. 14 In cases of progressive disease injury, it may be difficult to fix any date as the date of injury. Also, when the disease has been progressing through successive employments by more than one employer, some rule is needed for deciding which employer should be liable for the one injury created by the definition. Subsection (1) of s 16 dealt with these matters. It was as follows: "(1) If an injury consists in the aggravation, acceleration, exacerbation or deterioration of a disease: (a) the injury shall, for the purposes of this Act, be deemed to have happened: (i) at the time of the worker's death or incapacity; or (ii) if the death or incapacity has not resulted from the injury - at the time the worker makes a claim for compensation with respect to the injury; and (b) compensation is payable by the employer who last employed the worker in employment that was a contributing factor to the aggravation, acceleration, exacerbation or deterioration." Thus, (1), s 16(1) fixed a date when a progressive disease injury was deemed to have happened; and (2), the liability to pay compensation for a progressive disease injury was put upon the last employer of the worker in employment that was a substantial contributing factor to the injury, thus adding the word " substantial " to the otherwise identical words in the relevant part of s 4(b)(ii). 15 Section 22(1) of the Act provided that if death or incapacity of a worker resulted from more than one injury to the worker, liability to pay compensation was to be apportioned. Various members of this court found difficulties in this section: see Insurers Guarantee Fund NEM-General Insurance Ltd v GIO General Ltd (1994) 33 NSWLR 247 (from here on called the Insurers Guarantee case). One of these difficulties was dealt with by the insertion of s 22(1A) with effect as from 1 September 1995, Act 30 of 1995; see also Act 89 of 1995 and Sutherland Shire Council v Baltica General Insurance Co Ltd (1996) 39 NSWLR 87. This said, in part, that "... incapacity ... that results partly from one injury and partly from one or more other injuries is taken to have resulted from more than one injury." 16 The facts. The question of construction of s 16 which the appellant sought to raise in this appeal was argued by reference to the facts emerging from the following account. 17 The worker, who is the first respondent in the appeal, was employed, by an employer (Mr and Mrs Baker) whom I will call the first employer, starting on 14 March 1989, as a labourer picking mushrooms. In doing this work she gradually developed burning and stiffness in the knees. The first employer sold the mushroom growing business to the appellants in this appeal (Mr and Mrs Colliar), whom I will call the second employer, on 23 September 1991. The worker continued her employment picking mushrooms. The problems with her knees were gradually becoming worse. The second employer closed the mushroom growing business on or about 15 December 1992. The worker was then unemployed for about thirteen months. She then began employment with the second respondent in the appeal (Yancu Pty Ltd, (Yancu)), whom I will call the third employer. This work was that of a "laundry person/domestic" in a motel. She continued to have problems with her knees but was able to do the work. 18 Then, on 6 October 1995 there was an incident at work about which she gave the following evidence: "Q. Something happened to you on 6 October 1995. A.---That's right. Q. What was that. A.---Well, I was cleaning a spa, I had sprayed the tiles above the spa. Q. Where was the spa. A.---In Room 10 at the motel. Q. You were cleaning the bathroom, were you. A.---Yes, the spa area was separate to the bathroom and I was cleaning the spa area which was tiles and the spa, and I'd sprayed it with cleaner and stepped into the spa to do the tiles and I just slipped and crashed down on my knees in the spa. Q. When you crashed down on your knees in the spa how did you feel about yourself. A.---Well, do you mean did it hurt? Q. Yes, did it hurt. A.---Yes, it hurt. Q. What part of your body did you hurt. A.---My knees. Q. When you fell how badly did you feel, how strong was the pain. A. It was pretty bad but I - after a few minutes I was able to get myself together ... ... Q. ... Then how did you feel about yourself when you got home. A. Well, I - when I got home and sat down and then I couldn't walk, it was just, it was really bad. Q. The pain was really bad. A.---Yes. Q. So it was getting worse, was it. A.---Yes. Q. What happened then, did you go and see someone. A.---That was actually a Friday when that happened and Keiren, the manager, he wasn't there that day anyway. No, I just put up with it until - Q. This was on the - the accident you had was on 6 October 1995. A. Yes. Q. Did you go back to work. A.---No, I didn't go back again until the 12th, when Keiren rang me to go back to work I said I couldn't go back in because I'd hurt my knees. ... Q. So you had spent 6 days at home, had you, approximately. A. Yes. Q. How did you feel during the 6 days, were your knees getting better or worse or stable, or what. A.---No, they - mainly the right one, it was pretty bad. Q. What about the left one, was that also painful. A.---It was a bit sore but it wasn't like the other one. The other one was the worst but like it affected both of them but mainly the right one." The worker then said that she had only gone back to work on one day after 6 October 1995. She was asked about this day: "Q. Would it have been about 13 October. A.---Well, it could have been, I'm not sure, and then - and I couldn't stand it, it was just killing me so I knew I couldn't do it so then I went to the doctor, that would have been the 19th and I had cortisone injection into that knee on that day. Q. How did you feel after the cortisone injection. A.---Well, I did get some relief from it after about 4 or 5 days it did seem to feel a little bit better." 19 The worker was then asked how it had come about that on 15 December 1995 she had ceased working with the motel. She said the manager had rung and asked whether she was going to come back or not and she had said "I can't, I can't stand the pain, it's - I can't do it". She then gave evidence that her general practitioner had referred her to a specialist who "... said he thought that I'd had torn cartilage or something in my knee and that he could possibly tidy it up with an arthroscopy ..." 20 The worker had the recommended arthroscopy and a later one also. She had other treatment. She did not think her condition had been improved. She said her condition had been about the same since shortly after the second arthroscopy. She had obtained some relief from cortisone injections. Asked whether if she had not had the fall at the motel she would have continued with the work at the motel she said "Possibly, yes"; she also said it had been her intention to continue. Counsel for one employer, when cross-examining the worker, asked "Would you agree with me that ever since that fall (of October 1995) your knees have been a lot worse". She answered "That's right" (Black AB 12 S). 21 The cross-examination by counsel for another employer was as follows: "Q. Mrs Bulley, I take it from what you said that you started to get problems in 1989. A.---Yes. Q. In your knees, gradually, gradually got worse over a period of time and in 1995 you had the fall on both knees which made your knees the worst they had ever been. A.---That's right. Q. Since October 1995 your symptoms have continued to get worse and worse. A.---Yes." (Black AB 14 D-G) 22 Cross-examination by a third counsel was considerably longer, and it is not necessary to set it out verbatim. The object of the cross-examination was to obtain evidence from the worker which would support a submission that what happened to her on 6 October 1995 was part of a process of aggravation, acceleration, exacerbation or deterioration of an arthritic condition and thus part of a progressive disease injury and not a frank injury. If the court were persuaded of this, the submission would then be made that s 16 applied, the worker would be held to have suffered one injury and the third (and last) employer would alone be liable to pay the worker's compensation entitlements. Counsel obtained answers from the worker agreeing that her knees had got progressively worse since 1989, that there would be good days and bad days, and that the fall on 6 October 1995 "was just an incident which you recall now which caused pain in your knee". However, counsel, seeking to improve the position, further asked whether there were other incidents and got the reply: "A. Well, not as - no other incidents as bad as what that fall was that day. That was - Q. But there were other incidents in the past where you'd done something in an unguarded fashion which has caused pain. A. Well, I guess so, but nothing like what happened that day. Q. It was bad on that day and as I think you have told us, you went to the doctor over a period of time and she gave you medication in the form of injections. A.---Yes. Q. And the pain settled down. A.---To some extent, yes." (Black AB 15 D-G) 23 It seems clear from the way in which counsel for the three employers cross-examined the worker that the first and second employers were seeking as their best result a finding by the court that the case was entirely a s 16 case which would leave the third employer solely liable for the worker's compensation and that the third employer was seeking to avoid that position by showing there had been more than one injury to the worker, namely, (i) a progressive disease injury up to 6 October 1995 and (ii), a separate injury on that date not being a progressive disease injury but a frank injury (that is, as earlier indicated, one falling merely within what in every day language would be called an ordinary injury, which corresponds in my view with the "injury" defined in s 4(a) of the Act). 24 As the classification of what happened on 6 October 1995 was a live issue at the trial, it would have been helpful for the trial court (and as it happens, more so for this court, which does not have the same unremitting exposure to specialist medical knowledge as the judges in the Compensation Court) if there had been medical evidence before the court explaining the mechanism by which, if it were the case, the fall on 6 October 1995 made the worker's arthritic condition worse than it would have been in the progress it would have followed but for the fall on that date. Nothing of this kind was explicitly dealt with in the various medical reports tendered at the trial. None of the doctors whose reports were in evidence was called to give oral evidence. This rather unsatisfactory state of the evidence came to be the basis upon which counsel for the appellants made one of his submissions. 25 Trial judge's findings. The trial judge began her reasons by saying that as against the first and second employers the worker relied on the nature and conditions of her employment. This meant the worker was relying on injury within s 4(b). The trial judge said that as against the third employer the worker relied " upon a frank incident on 6 October 1995 ", that is a s 4(a) injury. 26 In dealing with the evidence, the trial judge said that it established overwhelmingly that following the incident of October 1995 there was a significant increase in symptoms in the worker's right leg more severe than in the left. She said the condition of the worker's knee had continued to deteriorate up to the time of the hearing. She said the evidence also established overwhelmingly that the worker had suffered a permanent loss of the efficient use of both legs of some significance with the right worse than the left. This finding was not disputed in the appeal. The trial judge went on to say that the evidence also established overwhelmingly that the worker's symptoms and restrictions were due to advanced osteoarthritis of the knees and that the degenerative changes pre-dated the commencement of her employment with the first employer, although the judge accepted the worker's evidence that she was asymptomatic prior to that time. The judge said further that a number of the doctors considered the losses (of the efficient use of the legs) were due at least in part and in varying degrees to the worker's work on the mushroom farm and the "frank incident" of October 1995. She added that all of the doctors were of the view that the fall of October 1995 "further aggravated" the degenerative changes in the right knee. 27 The trial judge then found, "Having regard to the totality of the evidence" that, on the balance of probabilities the worker's employment with the first and second employers was a contributing factor to the aggravation of her osteoarthritic disease. She also found that on 6 October 1995 the worker "suffered a frank injury to the knees in the employ of the [third employer] such injury being in the nature of a further aggravation of degenerative changes." A little later she said that because of her finding that the worker suffered a frank injury on 6 October 1995 " albeit in the nature of aggravation of degenerative changes ", s 16 had no application to the finding in regard to the third employer. She made clear why she reached this conclusion by the following passage in her reasons: "The applicant did not rely upon the nature and conditions of her employment with the fourth respondent [the third employer] and what I have not found is that the fourth respondent last employed the applicant in employment which was a contributing factor to the aggravation which would invoke the operation of s 16(1)(b)." 28 The trial judge found s 16(1)(b) did apply as against the first and second employers. She therefore found two injuries, the deemed date of the first of which was the last day of employment with the second employer, 15 December 1992 (this being a s 4(b)(ii) injury), and the second injury, suffered on 16 October 1995 (this being a s 4(a) injury). 29 Because, on her findings, there were two injuries, s 22 of the Act required the judge to apportion the liability to pay in such manner as she determined. The operation of s 16 meant that in regard to the first injury the second employer was liable so that the apportionment took place between the second employer and the third employer. The trial judge apportioned 60% of the liability to the second employer and 40% to the third. These apportionments were not challenged in the appeal. 30 The appeal arguments. Basic to the appeal, and accepted as such by counsel for the appellants, was that it was limited to points of law; the appellant had no appeal against findings of fact. 31 The point in the appeal for which the appellants wished to contend was that the trial judge should have found that the incident of 6 October 1995 was not a separate, ordinary, injury but was part of a progressive disease constituting only one injury for the purposes of the Act and thus to be dealt with pursuant to s 16 and leaving the third employer solely liable for the worker's compensation. 32 This submission had two branches. The first was that although the trial judge had found that the injury suffered in the employment of the third employer was a frank injury, nevertheless, because she had also found that it was in the nature of aggravation of degenerative changes and because, (it was contended), that description satisfied the terms of s 16, s 16 had, as a matter of law, to be applied. The second branch was that if the first branch failed, then there was no evidence upon which the trial judge could have found that the relevant injury was a frank injury. 33 It will be easier to explain the various reasons why I think the first branch of the submission must fail if I first state my opinion on the second branch, which, to repeat it, was that there was no evidence to support the trial judge's finding that the injury in the third employer's employ was a frank (s 4(a)) injury. The rather unsatisfactory state of the medical evidence which I earlier mentioned gave the appellants a slightly specious basis for this submission. 34 Notwithstanding this, there was, in my opinion, ample evidence before the trial judge that the worker suffered a frank injury on 6 October 1995. Probably her own evidence was sufficient. She was at work, she slipped, she fell, she hit her knee, she suffered pain as a result, and from then on she had significantly more difficulty in trying to use the knee than she had had before. This might be an unsophisticated way of approaching the point, but to my mind a proper and sufficient one. However, the evidence of the worker was not the only evidence. In one of the medical reports in evidence Dr Gibson said: "Marilyn first began work at J & K Mushrooms in 1989. She mentioned soreness in her knees from 1990 onwards, however it wasn't until early 1992 that her symptoms warranted x-rays and orthopaedic opinion. She was assessed by Dr Hyde-Page at this stage. During this period she was working at the mushroom farm, kneeling on concrete, then climbing ladders throughout her hours of employment. It was quite evident at the time that she was developing a disease process whilst she worked. It is clearly my opinion that this progress was directly related to the nature of her work, and would not have occurred were she not working in that particular job. She further aggravated and advanced her disease whilst working at the Riverview Motel, Taree, where she slipped whilst cleaning a spa, landing forcefully onto both knees. I attributed liability as follows: 60% to the time she worked at the Mushroom Farm, 30% when she slipped in the spa and 10% to natural progression of an underlying tendency to osteoarthritis." 35 It seems reasonably clear to me that in this passage Dr Gibson was drawing a distinction between, on the one hand, the worker's employment by the first and second employers at the mushroom farm where she was developing a "disease process" (sic) while working, that "progress" (sic) being directly related to the nature of her work and such as would not have occurred if she were not working in that particular job and, on the other hand, her later employment with her third employer where she slipped landing forcefully on her knees, suffering an injury not of a progressive kind. It seems to me the only reasonable way of reading her percentage allocations at the end of the quoted part of her opinion is that 60% of her disability was attributable to the progressive aggravation of her disease while working for the first and second employers, 30% to the distinct injury she suffered when she fell and 10% to what would have happened to her in any event regardless of her employment at the mushroom farm and the injury at the motel. It follows from this that in my opinion the "no evidence" argument fails. 36 The only other way the appellant might conceivably hope to overcome the trial judge's factual findings (which I should mention in passing, were in my opinion fully open to her) would be by a submission that, as a matter of law, it followed from the factual findings she did make about the injury of 6 October 1995 ("a further aggravation of degenerative changes" etc), that the injury was a progressive disease injury and only a progressive disease injury. This however simply fails on the facts. Zickar holds that an injury can be both a s 4(a) injury and a s 4(b) injury. When it is, an applicant worker can, as here, rely simply on the s 4(a) injury. Zickar establishes this also. There was evidence on which the trial judge could and did find the relevant injury was a s 4(a) injury. The judge's finding on that evidence defeats the submission. 37 A lesser, but also fatal, point is that to uphold the submission, this court would have to hold that as a matter of fact, the worker's employment with the third employer was a contributing factor to progressive osteoarthritic damage to the worker's knee on 6 October 1995. This court has no power in this appeal to make factual findings. 38 I return now to the first branch of the appellants' submission, on which most time in the argument was spent. 39 With all respect to others who take a different view, this submission is not acceptable. It overlooks altogether the judge's statement that the worker's claim against the third employer was that she had suffered (received, as the Act says) an injury in that employer's employment within the meaning of s 4(a). As Zickar held, the applicant was quite entitled to put that part of her case on that basis, if the facts supported it. The judge held they did. The appeal is confined to questions of law. If there was material upon which the judge could make a finding of a s 4(a) injury, then her finding cannot be questioned in this court. 40 On the footing that the trial judge upheld the worker's claim that her injury in the third employer's employment was a s 4(a) injury, there was no need for her to consider whether the worker's injury could also be classified as a s 4(b) injury, nor was there any point in her doing so. Nor did the judge consider the question. This is made crystal clear by her statement that she had not found as a fact that the worker's employment with the third employer was a contributing factor to the injury the worker suffered in that employment. In the absence of such a finding, (i), an essential ingredient of a s 4(b) progressive disease injury was missing, (ii), it was impossible to conclude there had been such an injury and (iii), no question about the operation of s 16 in regard to the injury in the third employer's employment could arise. 41 In my opinion this branch of the appellants' submission cannot succeed. 42 On the views I have expressed, this court never reaches the main point the appellants wished to argue, but I will note it nevertheless. This point depended upon a view of the trial judge's findings which for reasons already given I do not think is sustainable, that is, the submission went upon the basis that when the trial judge referred to the injury of 6 October 1995 as being a frank injury "albeit in the nature of aggravation of degenerative changes" she was either making a finding or was bound to make a finding that the injury was both a frank injury and a progressive disease injury. 43 Starting (inadmissibly) from there, the argument was that in an overlapping situation where the court finds that the same incident falls within the description both of a frank injury and a progressive disease injury, s 16 must be applied. This contention then became the main focus of the appellants' argument. 44 My own opinion on the argument, if it were necessary to reach a conclusion on it, is to the opposite effect: namely, that if an injury falls into both categories, and the worker relies on, and the court finds a s 4(a) injury, then s 16 has no application. This clearly follows from both majority opinions in Zickar. 45 To avoid this conclusion the appellants sought to rely on MLC Insurance Ltd v Pinto (1994) 10 NSWCCR 101; they also sought to bolster what was said to be the continuing effect of that decision with the comment made in the High Court in QBE Insurance Ltd v Switzerland Insurance Workers Compensation (NSW) Ltd (1996) 70 ALJR 281 in which the court said that "It [was] certainly arguable that Insurers Guarantee Fund NEM General Insurance Ltd v GIO General Ltd (1994) 33 NSWLR 247 establishes that, when a worker has a single partial incapacity caused by a succession of injuries, the insurer who is liable for that incapacity is the insurer who was on risk when the last causative injury occurred. According to that decision, insurers who were on risk in respect of the earlier injuries are not liable to contribute." (at 283) 46 There are a number of problems for the appellants in their reliance on these two decisions. In regard to Pinto, what was decided in that case was not applicable to the facts of the present case, even if the present case were being decided on the law as it stood when Pinto was decided. In Pinto, Clarke JA said that the provisions of s 16(1)(b) and (2) provided in effect a code in disease cases so that there was no room for apportionment of liability to a worker between employers (at 107). This view was partly based on the then standing authority of the Insurers Guarantee Fund case. Clarke JA went on to say, however, that there was a proviso, which he regarded as a remote possibility, to his conclusions. The proviso was that there might be a case "in which the incapacity is found to result from each of a frank injury and the aggravation of a disease" (at 107). He continued by saying that that however was not the case before the court (at 107). 47 A further difficulty with reliance on Pinto is that it depended upon the correctness of propositions laid down in the Insurers Guarantee Fund case which were subsequently overridden by amendments made to the Act in 1995. These amendments, among much else, inserted in the Act the s 22(1A) referred to in par 15 above. In a set of cases heard consecutively to consider the effect of the amendments, (see Sutherland Shire Council v Baltica General Insurance Co Ltd (1996) 39 NSWLR 87) Clarke JA (with whom Hunter AJA and I agreed) accepted that the legal position had been substantially altered by the amendments. Part of what was required under the changed system was factual findings by the trial judge whether the particular incapacity in a case resulted partly from one injury and partly from another injury or other injuries. Clarke JA made it quite clear that in answering these questions the trial judge would be deciding questions of fact (at 94). 48 In short, Pinto is neither an authority on the facts of the present case nor on the relevant provisions of the Act which affect this case, materially different as they are from those in force at the time of Pinto. 49 The appellants have similar problems in relying on the observation made by the High Court in QBE Insurance concerning the arguability of the point that court defined in light of the Insurers Guarantee Fund case. The High Court's decision in QBE Insurance was that the point they there isolated as arguable, which had not been dealt with when the case was heard on appeal in this court, should be considered and decided by this court. As directed, this court considered the point and handed down its reasons and decision on 5 December 1996 under the name Switzerland Insurance Workers Compensation (NSW) Ltd v Burley. So far as I know, the decision is unreported. Mahoney P came to the conclusion that the Insurers Guarantee Fund case did not establish the proposition which the High Court had held was arguable. The other two judges (Meagher JA and myself) dealt with the case differently. Assuming without deciding that the Insurers Guarantee Fund case did establish the proposition said by the High Court to be arguable, the further point was made that in light of the retrospective changes to the legislation that had been made as discussed in Baltica General Insurance since this court's first decision in the Switzerland Insurance case and since those amendments were retrospective and brought about the same result as the court had originally arrived at in any event, then the court should dismiss that ground of appeal, because the question of apportionment would, even if the arguable proposition were held to be correct, have to be decided on the newly current law, which made that proposition inapplicable. 50 A decision which the appellants very properly brought to the notice of the court as being possibly inconsistent with their contention, as indeed, in my opinion, it is, was Australian Conveyor Engineering Pty Ltd v Mecha Engineering Pty Ltd (1998) 45 NSWLR 606. The appellants sought either to distinguish the facts of this case from the present or to have this court overrule it as being inconsistent with Pinto. 51 In Mecha Engineering Sheller JA concluded that s 16 was confined to what were entirely aggravation injuries (at 616). Powell JA said that given the trial judge's findings of fact and what had been decided by the High Court in Zickar: "it was open to the trial judge to hold that the worker's impairments were due to two discrete 'injuries' - a simple 'injury' in 1992 and an 'injury' brought about by the nature and conditions of his employment with the first respondent and that he did not err in doing so. This being so, it seems to me that the case did not call for the application of the provisions of s 16 of the Act." (at 619) 52 Fitzgerald AJA dissented. 53 There can be no question of Mecha Engineering being inconsistent with Pinto in any relevant sense, because it was decided on later and different legislation, as explained by Clarke JA in Baltica General. Pinto remains an authority on the law with which it dealt and Mecha Engineering in my opinion is an authority which should be followed in the present case. Sheller JA's opinion goes further than that of Powell JA and I would conclude that since Sheller JA's proposition includes that of Powell JA, then the lesser proposition of Powell JA should be treated as the governing rule that emerges from the case. 54 Thus, in my view, the case law relied on by the appellants can be of no assistance to them. Zickar by itself, in conjunction with the relevant statutory provisions governing the present case, in my opinion requires this court to agree with the legal basis on which the trial judge proceeded. Further, Mecha Engineering likewise requires this court to come to the same conclusion, or if that be putting the authoritative effect of that decision too high, it is at the very least strongly persuasive in support of the trial judge. 55 I therefore would not accept the first and principal branch of the appellants' submission even if it were arguable on the facts. 56 Conclusion. Put shortly, the course of the trial judge's reasoning was that she found there was a frank injury on 6 October 1995, therefore no question of the application of s 16 arose in regard to that injury. Further, although perhaps less fundamentally, she did not find there was progressive disease injury on that day, so again no question of the application of s 16 arose. On the facts of the case as the trial judge found them, and in my opinion was entitled to find them, her line of reasoning seems to me to be fully valid. In my opinion the appellants have been unable to show that the trial judge made any error of law in her decision. 57 In my opinion the appeal should be dismissed with costs. 58 MEAGHER JA: I agree with Davies AJA. 59 DAVIES AJA: This is an appeal from a determination of the Compensation Court of New South Wales. The issue is whether the provisions of s 16 of the Workers Compensation Act 1987 ("the Act") should have been applied so as to exculpate from liability Mr and Mrs Colliar, who are the present appellants and were the third respondents below. As the appeal is brought under s 32 of the Compensation Court Act 1984, it is limited to a question of law. 60 Section 9(1) of the Act provides, inter alia: (1) A worker who has received an injury (and, in the case of the death of the worker, his or her dependants) shall receive compensation from the worker's employer in accordance with this Act. 61 Section 16 of the Act provides, inter alia: (1) If an injury consists in the aggravation, acceleration, exacerbation or deterioration of a disease: (a) the injury shall, for the purposes of this Act, be deemed to have happened: (i) at the time of the worker's death or incapacity, or (ii) if death or incapacity has not resulted from the injury - at the time the worker makes a claim for compensation with respect to the injury, and (b) compensation is payable by the employer who last employed the worker in employment that was a substantial contributing factor to the aggravation, acceleration, exacerbation or deterioration. (2) Any employers who, during the 12 months preceding a worker's death or incapacity or the date of the claim (as the case requires), employed the worker in any such employment shall be liable to make to the employer by whom compensation is payable such contributions as, in default of agreement, may be determined by the Compensation Court. 62 Section 22 provides, inter alia: (1) If: (a) the death or incapacity of a worker, or (b) a loss suffered by a worker as referred to in Division 4 of Part 3, or (c) a liability under Division 3 of Part 3 to a worker, results from more than one injury to the worker, liability to pay compensation under this Act is to be apportioned in such manner as the Compensation Court determines. (1A) Death, incapacity, loss or liability that results partly from one injury and partly from one or more other injuries is taken to have resulted from more than one injury. 63 Mrs Bulley commenced employment as a labourer picking mushrooms with Mr and Mrs Baker, who were the first respondents below. The job required her to kneel on a concrete platform to pick mushrooms. The floor was generally wet and cold. She also had to climb up and down about four or five rungs of a ladder to pick from a top level. In 1991, that business was acquired by Mr and Mrs Colliar. Until the business closed on or about 15 December 1992, Mrs Bulley continued to perform the same work, which aggravated the underlying osteoarthritic condition in her knees. 64 After a break, Mrs Bulley commenced employment with Yancu Pty Limited, the fourth respondent below and the second respondent in the appeal. Yancu Pty Limited operated a motel. On 6 October 1995, Mrs Bulley sprayed a spa area with cleaner and, when she stepped into the spa, she slipped and landed heavily on both knees. A claim for compensation was made thereafter. 65 The trial Judge made the following findings of fact: "The evidence establishes overwhelmingly that the applicant's symptoms and restrictions are due to advanced osteoarthritis of the knees and that the degenerative changes pre-dated the commencement of her employment with the first respondent, although I accept her evidence that she was asymptomatic prior to that time. Drs Burke and Potter are of the view that the losses result from the constitutional condition of her knees unaffected at least on a permanent basis by her work with any of the respondents. All of the other doctors consider that the losses are due at least in part and in varying degrees to her work on the mushroom farm and the frank incident in October 1995. … As to the applicant's employment with the first and third respondents, having regard to the totality of the evidence I am satisfied on the balance of probabilities that this employment was a contributing factor to the aggravation of the disease. I am also satisfied that on 6 October 1995 she suffered a frank injury to the knees in the employ of the fourth respondent such injury being in the nature of a further aggravation of degenerative changes. In this regard I reject the opinions of Drs Potter and Burke." 66 The trial Judge made an award for weekly payments as against Yancu Pty Limited only. However, having ordered compensation under s 66 of the Act for permanent injury and under s 67 for pain and suffering, her Honour ordered that the compensation so awarded be apportioned as to 60 per cent to Mr and Mrs Colliar and 40 per cent to Yancu Pty Limited. 67 Her Honour declined to apply s 16 of the Act against Yancu Pty Limited on the ground that Mrs Bulley proved a "frank injury" and did not rely upon "the nature and conditions of her employment". Had s 16 been applied against it, Yancu Pty Limited would have been solely liable, being the last employer. Section 16(2) would not have applied because of the time lapse. 68 The trial Judge found that Mrs Bulley's injury on 6 October 1995 was an injury "being in the nature of a further aggravation of degenerative changes". That finding accorded with the medical evidence which the trial Judge accepted. Dr Vote said that the fall in October 1995 was a "major turning point in the deterioration of the right knee". Dr Tooth said that the injury in October 1995 "appears to have been an aggravation of the pre-existing arthritis". Dr Thomson said, "The fall in the Spa appears to have been a significant aggravating incident". If there was any injury other than an aggravation to the ongoing arthritic condition in Mrs Bulley's knees, it was not identified in the evidence or by the trial Judge. 69 Mrs Bulley's injury satisfied the terms of s 16 in that it consisted in the aggravation, acceleration, exacerbation or deterioration of a disease. The finding by the trial Judge, which was based on the evidence, was that the nature of Mrs Bulley's injury was an aggravation of degenerative changes. No other injury was identified or relied on. 70 Section 4 of the Act defines "injury" in this way: (a) means personal injury arising out of or in the course of employment, (b) includes: (i) a disease which is contracted by a worker in the course of employment and to which the employment was a contributing factor, and (ii) the aggravation, acceleration, exacerbation or deterioration of any disease, where the employment was a contributing factor to the aggravation, acceleration, exacerbation or deterioration, … 71 In Zickar v MGH Plastic Industries Pty Ltd (1996) 187 CLR 310, Toohey, McHugh, Gummow and Kirby JJ, Brennan CJ, Dawson and Gaudron JJ dissenting, held that there is no complete dichotomy between injuries which fall within para (a) and those which fall within para (b)(ii). In that case, the occurrence at work of a cerebral aneurism, because of a congenital weakness, was held to be an injury in the course of employment. Throughout the judgments in that case are references to aspects of a disease which, in other cases, have been held to constitute a physical injury. Mention was made, inter alia, of a ruptured bowel, a ruptured oesophagus, the collapse of vertebrae and the rupture of blood vessels and consequent cerebral haemorrhage. At p 347, Kirby J said that what was required to constitute such an injury was a "sudden or identifiable pathological change". His Honour made reference to Willis v Moulded Products (Australia) Ltd [1951] VLR 58 in which, at p 69, Sholl J said that any ascertainable lesion, or lesion observable ante or post mortem, of part of the body was of itself and per se injury by accident. 72 I need not discuss that question any further. No doubt the decision in Zickar v MGH Plastic Industries Pty Ltd will give new life to the issue as to what is and what is not an injury for the purposes of para (a) of the definition. However, the width given to para (a) of the definition provides no reason for reading down the meaning of the words in para (b)(ii) thereof or the words of s 16. I accept that, if an aspect of a disease is compensable only because it constitutes an injury in the course of employment within para (a), that injury would not fall within the scope of s 16. I do not accept that an injury, which constitutes an aggravation or other exacerbation of a disease and to which the employment has contributed, falls outside s 16 simply because the claim for compensation was or could have been framed in terms of para (a) of the definition. 73 The approach taken by the trial Judge was inconsistent with the judgments of Clarke, Meagher and Handley JJA in MLC Insurance Ltd v Pinto (1994) 10 NSWCCR 101. In that case, the worker had received an injury to his back in 1983 in a "frank incident" in the course of employment with one employer and further injuries being "multiple traumata constituted by heavy work" in the course of employment with a later employer. It had been found, as a fact, that the injuries had aggravated the underlying degenerative disease of the worker's spine and that the incapacity resulted from the cumulative effect. It was held that s 16 applied and that s 22 did not. At p 106, Clarke JA said: "It may be true to say that section 16 was introduced into the Act as a means of removing some of the difficulties which arise when a worker who suffers from a disease, which is aggravated by employment conditions, has worked for two or more employers in the period leading up to his or her incapacity and that that is the major area of operation of the section. Nonetheless, the section is not expressly limited to that type of case and effect must be given to its words." At p 109, Handley JA, with whom Meagher JA agreed, said: "It is clear from the Judge's findings that the worker has a single incapacity due to the cumulative effect of the 'incident' of May 1983 and the nature of the worker's employment after his return to work. The last period of that employment occurred while QBE was on risk and in accordance with the Judge's findings section 16(1)(a)(i) deemed the injury which consisted of the aggravation of the worker's degenerative disease by his employment to have happened at the time of his incapacity in April 1988. It is clear therefore that the initial liability to indemnify the employer fell upon QBE alone." 74 In accordance with this approach, the trial Judge should have applied s 16. Her Honour erred in law by not doing so. 75 A submission put by counsel for Yancu Pty Limited was that s 16 applies only to those cases where the long-term incidents of employment, "the nature and conditions" of employment to use the words of the trial Judge, give rise to the aggravation, acceleration, exacerbation or deterioration of the disease. However, neither s 16 nor para (b)(ii) of the definition of "injury" are so limited. Employment may contribute to the aggravation, acceleration, exacerbation or deterioration of a disease either through the long-term nature and conditions of the employment or by the happening of a single incident. No words in para (b)(ii) of the definition of "injury" turn upon the nature of the contribution. Such a submission was specifically rejected in MLC Insurance Ltd v Pinto. 76 When s 16 applies, it applies as a code and excludes the operation of other provisions such as s 22. In MLC Insurance Ltd v Pinto, at p 109, it was pointed out by Handley JA, with whom Meagher JA agreed, that once s 16(1)(b) applies, there can be no ground for apportionment under s 22 since there is no common liability to apportion. Of course, s 16 applies only when the injury in respect of which compensation is sought consists in the aggravation, acceleration, exacerbation or deterioration of a disease. In Yates Bros (Stratford) Pty Ltd v Neil [1999] NSWCA 108 at [14], Handley JA, with whom Mason P and Stein JA agreed, said of the analogous s 15 of the Act: " Section 15 is a self contained code which deals exclusively with injuries of the kind which fall within its terms. One can express the same point by saying that it is a special provision which stands outside the general provision in s 22 ." 77 Counsel for Yancu Pty Limited has submitted that the trial Judge made a finding that Mrs Bulley's injury consisted in both an aggravation to her underlying condition and something more. He referred to the trial Judge's finding that Mrs Bulley suffered "a frank injury" in October 1995 and to Mrs Bulley's evidence regarding her fall when she said that, "I thought I'd torn something or something in there, because it felt like something was caught or something". However, no finding of an injury additional to an aggravation of the ongoing arthritic condition was stated by the trial Judge or was suggested by any of the doctors whose evidence the trial Judge accepted. 78 Counsel for Yancu Pty Limited also relied upon the decision of this Court in Australian Conveyor Engineering Pty Ltd v Mecha Engineering Pty Ltd (1998) 45 NSWLR 606. The judgments in that case did not refer to MLC Insurance Ltd v Pinto. Sheller JA adopted an approach similar to that now propounded by counsel for Yancu Pty Limited. Fitzgerald AJA took the contrary view. Powell JA held that there were two discrete injuries, one of which involved ligamentous injury to the lumbar spine segment, and that s 16 did not apply. In the light of these circumstances, I consider that that case cannot be regarded as a binding authority. 79 Section 16 should be applied having regard to the terms which it uses. The meaning gleaned from those words should not be read down by reference to imported considerations of justice and equity or by reference to terms such as "nature and conditions of employment" and "frank injury", terms which the section does not use. It is particularly important to give the words of s 16 their ordinary and full signification as the section is designed to reduce litigation. This end is further promoted by s 18 which provides for the administrative adjustment of premiums in the circumstances to which it applies, one of which is that the case is one to which s 16 applies. The aim of reducing litigation could not be achieved if complexities were introduced or if the application of s 16 were to depend upon the manner in which a worker's claim was presented at the hearing. 80 I would allow the appeal. I would order that Orders 9, 10 and 11 of the trial Judge's judgment be set aside and that, in lieu thereof, it be ordered that Yancu Pty Limited be liable for all the awards of compensation made in favour of Mrs Bulley. I would order that Mrs Bulley's claim against Mr and Mrs Colliar be dismissed. I would order that Yancu Pty Limited pay the costs below and the costs of the appeal. ********** DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. 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