Plaintiff v Defendant

1 This proceeding was commenced by Originating Motion on 7 March 2012. The plaintiff sought an order under O 56 of the Supreme Court (General Civil Procedure) Rules 2005, quashing that part of the Certified Opinion of a Medical Panel convened under s 68(6) of Accident Compensation Act 1985, being its answer to question 4. The Panel members are the first to fourth defendants. The plaintiff also sought an order that the fifth defendant, as Convenor of Medical Panels, cause the Panel to answer question 4 according to law.

2 The plaintiff's grounds for its application were as follows:

The Medical Panel erred in law in reaching its opinion in answer to question 4 to the effect that the sixth defendant had no current work capacity and this situation was likely to continue indefinitely, by reason of the following:

(a) It misinterpreted or misapplied the term 'no current work capacity', defined in section 5 of the Act as 'a present inability arising from an injury such that the worker is not able to return to work, either in the worker's pre-injury employment or in suitable employment', and impermissibly took into account a supervening left knee injury which was not compensable under the Act, thereby falling into jurisdictional error;

(b) The reasons of the Medical Panel and the evidence before it show that the Panel impermissibly took into account the effect of the worker's supervening left knee symptoms and signs and their effect in reaching its opinion that she has no current work capacity;

(c) The reasons of the Medical Panel demonstrate that it did not consider the submissions made by the Agent in forming its opinion.

3 Deberra Darbyshire, the sixth defendant, was injured at her place of work on 15 November 2004. She was employed by the plaintiff. She caught her right foot on matting and twisted her right knee. Her claim for benefits under the Act was accepted, and she received compensation payments until 14 May 2007, when payments were terminated based on a decision that she had a current work capacity. I will refer to Ms Darbyshire as the worker.

4 Notwithstanding knee surgery in February 2005, the worker's knee deteriorated. She disputed the termination of weekly payments and a magistrate referred questions to a Medical Panel under s 45(1)(b) of the Act. On 5 May 2008, a Panel expressed the opinion that the worker had a current work capacity.

5 In December 2010, the worker underwent further surgery, involving the replacement of her right knee. At the time her left knee was also causing her severe discomfort and on 20 January 2011, a little over a month after the right knee replacement, Mr Cameron Norsworthy, Orthopaedic Surgeon, wrote to the plaintiffs' insurer requesting funding for a left knee replacement. The insurer rejected the request and denied any liability, stating:

Allianz has obtained information from Mr Cameron Norsworthy which indicates that this surgery is needed for a condition that is not related to your work-related injury or illness. Your accepted WorkSafe claim is for your right knee and this surgery is required for your left knee.

... As your left knee condition is not related to your accepted work-related injury, Allianz is unable to approve this request.

6 The worker subsequently referred the denial of liability as a dispute for conciliation, and on 30 September 2011 the dispute was referred to the Panel, which was required to answer the following 'Medical Questions':

1. What is the nature of the worker's medical condition of the left knee (including any sequelae) relevant to the claimed injury to the right knee?
2. What is the extent to which any medical condition resulted from or was materially contributed to by the injury?
3. Do you consider the medical services or the proposed medical service namely, a left knee replacement adequate and appropriate for the worker's injury?
4. Does the worker have no current work capacity? If so, is this condition likely to continue indefinitely?

7 At the time of the referral, the Panel was provided with the following documents:

(1) Referral and questions to Medical Panel, dated 30 September 2011.

(2) Notice of rejection dated 2 February 2011.

(3) Letter dated 31 May 2011 from Dr DJ McColl to the insurer and the Accident Compensation Conciliation Service.

(4) Letter dated 20 January 2011 from Mr Norsworthy to the insurer.

(5) Report dated 21 June 2011 from Mr Norsworthy to the insurer.

(6) Report dated 15 August 2011 from Mr Clive Jones, orthopaedic surgeon, to the insurer.

(7) Letter dated 18 August 2011 from Mr Jones to the insurer.

8 The report mentioned in item (3) above, dated 31 May 2011 and prepared by Dr McColl, was apparently in response to questions that had been posed for his consideration by the insurer, or the insurer and the Accident Compensation Conciliation Service. Dr McColl wrote,

1. Mrs Darbyshire suffers from severe medial compartment osteoarthritis of her left knee. Mrs Darbyshire had a right total knee replacement on the 13.12.10 for a work-related right knee injury. Her left knee osteoarthritis has worsened over the years due to her weightbearing through her left leg to protect her work-related osteoarthritic right knee over this time.
2. As stated previously Mrs Darbyshire has developed osteoarthritis of her left knee due to preferentially weight bearing through this leg to protect her previous work-related right knee osteoarthritis.
3. Her left knee problems are a direct sequelae to her right osteoarthritic knee problems as described before.
4. Mrs Darbyshire has no capacity to work in her pre-injury job as(sic) any other job at present due to her left knee problems.
5. As stated previously Mrs Darbyshire is not able to work in any suitable capacity.
6. Mrs Darbyshire's incapacity is NOT indefinite. I believe if she has surgery on her left knee, either a partial or full knee replacement she will be able to return to the workforce.
7. It is essential that Mrs Darbyshire has surgical treatment of her left knee to return to work. She will require extensive post-operative rehabilitation initially as an inpatient and then as an outpatient to fully recover so she can work. Mrs Darbyshire can currently attend to all ADL's such as showering, dressing etc. but with some difficulty due to ongoing left knee pain. Obviously this will also improve post-surgery and rehabilitation of left knee.

9 Thus, in Dr McColl's opinion, the condition of the worker's right knee had accelerated a degeneration in her left knee, although the osteoarthritic condition of the left knee pre-dated the right knee injury. He concluded that the worker had no present work capacity but, with a partial or full left knee replacement, would be able to return to work.

10 The report mentioned in item (5) above, dated 21 June 2011 and prepared by Mr Norsworthy, was also in response to a request from the insurer. Mr Norsworthy stated:

Diagnosis

The left knee is affected by significant medial compartmental and patellofemoral joint osteoarthritis. This has developed slowly over a number of years, and in my opinion has progressed in an accelerated fashion owing to the many years in which she was suffering from her right knee condition, which was the subject of a WorkCover claim.

Relationship to Employment

The left knee condition is not related to the patient's employment, but has been exacerbated by the work related injury that was sustained by the right knee.

Current Incapacity

The patient's current medical condition and incapacity is directly a result of the right knee injury sustained at work.

Current Capacity for Pre-Injury Duty

It is my understanding that the patient is unable to perform any of her normal duties at present.

Current Ability to Work

It is my understanding that the patient is currently unable to perform any work.

The current incapacity to work is likely to continue until she has recovered from her left knee condition. It is my plan that she undergoes a left total knee replacement to treat the severe osteoarthritis. Providing she makes a routine recovery from that surgery, and continues to do well from her right knee replacement, it would be expected that she would attempt a return to work approximately six weeks after the surgery.

It is my opinion that the patient's general health and ability to undertake the activities of daily living will further deteriorate if she does not undergo the planned left total knee replacement. It is my understanding that she is currently unable to perform some of her own toileting and dressing tasks, and that she is unable to perform some of the simple household duties such as the preparation of food.[2]

11 Mr Norsworthy's opinion was generally consistent with Dr McColl's. Mr Norsworthy had opined, 'the left knee condition is not related to the patient's employment, but has been exacerbated by the work related injury that was sustained by the right knee', and Dr McColl had opined that the worker's 'left knee problems are a direct sequelae to her right osteoarthritic knee problems'.

12 The report mentioned in item (6) above, dated 15 August 2011 and prepared by Mr Clive Jones, Orthopaedic Surgeon, was also made to the insurer. Mr Jones was also asked a series of questions and gave the following answers by letter dated 18 August 2011:

1. Do you believe that the worker's left knee condition is materially contributed to by the initial injury that occurred on 15/11/04? i.e. is it as a direct consequence of the right knee injury?

The November 2004 injury was to the right knee and not the left. The left knee was not injured as a result of that event.

1. In your clinical opinion, is the worker's injury an aggravation, a recurrence, an acceleration, an exacerbation or a deterioration of any pre existing injury or disease? Please explain your opinion.

The worker's right knee injury was certainly an aggravation of a pre existing injury or disease. The left knee was not subject to any such aggravation and had only become symptomatic more recently.

1. Do you believe that the worker's left knee condition is constitutional in nature?

I firmly believe this lady's left knee condition is constitutional in nature. The x-rays show equally developed arthritic change in both knee joints.

13 The opinions expressed by Mr Jones were not always responsive to the questions asked. The difficulty, however, was that the questions were not expressed in terms that might elicit a useful answer, if the inquirer's objective was to ascertain whether, and to what extent, the current condition of the left knee was caused or contributed to by the injury to the right knee. When reading the report and letter from Mr Jones, he may be taken to have expressed an opinion that the condition of the left knee had not been aggravated by the workplace injury because the worker suffered 'symmetrical knee osteoarthritis' that was 'undoubtedly constitutional in nature'.

14 What seems apparent from the opinions expressed by these three practitioners is that, while there were differing views about the relationship between the condition of the left knee and the workplace injury, it was not clear that the opinions were directed to precisely the same issue. There is some uncertainty as to whether the connection made between the workplace injury and the left knee was between the injury and the current condition of the left knee, or between the injury and the 'origin' of its condition, described as constitutional. That distinction might be crucial. Thus, while it may have been accepted that there was no connection between the workplace injury and the 'origin' of the condition of the left knee, it may have been open to the Panel to conclude, as did Mr Norsworthy, that a pre-existing condition of the left knee 'had been exacerbated by the work related injury'.

15 In early May 2011, the worker made application for the reinstatement of weekly compensation payments. By letter dated 21 October 2011, the insurer rejected the application. The worker referred the insurer's rejection as a further dispute to a conciliator who, in turn, amended the referral to the Panel. The following additional material was provided to the Panel:

(1) The conciliation cover letter and the amended referral both dated 21 November 2011.

(2) The Medical Panel opinion and reasons dated 5 May 2008.

(3) A vocational assessment report prepared by Resolve Rehabilitation Services Pty Ltd dated 31 January 2007.

(4) Their letter dated 21 October 2011 from the insurer rejecting the application for the reinstatement of weekly payments.

(5) Written submissions prepared on behalf of the insurer for consideration by the Medical Panel dated 7 December 2011.[3]

16 In its written submissions to the Panel, mentioned at item (5), the plaintiff contended,

Mr Jones is of the opinion that the worker's left knee condition is not related to her employment.

The definition of 'no current work capacity' in section 5 of the Act refers to 'a present inability arising from an injury'. The word 'injury' must be a reference to the compensable injury and the 'inability' to return to suitable employment must arise from that injury. The definition of 'suitable employment' does not refer to other non work-related medical conditions.

Accordingly, a non work-related supervening injury or medical condition should not be taken into account when determining whether a worker has a current work capacity.

17 On 9 January 2012, the Panel certified the following opinions in answer to each of the questions mentioned above:

Question 1.

What is the nature of the worker's medical condition of the left knee (including any sequelae) relevant to the claimed injury to the right knee?

Answer:

In the Panel's opinion, the worker is suffering from constitutional osteoarthritis of the left knee, which is not relevant to any injury to the right knee.

Question 2.

What is the extent to which any medical condition resulted from or was materially contributed to by the injury?

Answer:

The Panel is of the opinion that the worker's current right knee condition and her chronic adjustment disorder with mixed anxiety and depressed mood are still materially contributed to by the claimed injury to the right knee, but the osteoarthritis of the left knee is constitutional in origin does not result from and is not materially contributed to by the claimed injury to the right knee.

Question 3.

Do you consider the medical services or proposed medical services namely, a left knee replacement, appropriate and adequate for the worker's injury and/or condition?

Answer:

Not applicable.

Question 4.

Does the worker have no current work capacity? If so, is this situation likely to continue indefinitely?

Answer:

In the Panel's opinion, the worker has no current work capacity and this situation is likely to continue indefinitely.

18 An issue before the Panel, raised by the plaintiff in its submissions, and by the medical reports, was the connection, if any, between the workplace injury and the current untreated condition of the left knee. That issue was probably intended by the authors of the questions to be reflected in the first question. Unfortunately, the first and second questions were poorly framed and unhelpful. There was no challenge to the opinions given in answer to questions 1 and 2. It is not surprising that the plaintiff did not challenge those opinions, as the answers were pivotal to its case, by demonstrating inconsistency in the answer to question 4, when read with the reasons.

19 The first question was confusing. The opening word, 'What', may be erroneous. Even making that allowance, the question inquired as to whether the condition of the left knee (including any sequelae) was 'relevant' to the claimed injury. Presumably, the intention was to focus on the current condition of the left knee, although one cannot be certain. But to ask about 'relevance' was, in my view, to misdescribe the inquiry that ought to have been made, if the intention was to inquire whether the current condition of the left knee arose or resulted from, or had been contributed to by, the injury to the right knee. Even that question had its limitations in the context of this case unless coupled with some legal assistance.

20 The generality of question 2 made it ambiguous. The Panel was no doubt attempting to provide a useful answer by identifying conditions that were attributable to the 'claimed injury to the right knee'. Curiously, one such condition identified by the Panel was the 'current right knee condition'. The Panel, however, moved on to consider the left knee and responded in the same vein as it did in response to question 1. That is, as if concerned with a connection between the origin of the left knee condition and the workplace injury, rather than the current condition of the left knee and the workplace injury.

21 The difficulty in formulating the correct questions, which in my view may go some way to explain the apparent inconsistency between the opinions expressed in the medical reports and the answers given by the Panel, is not assisted in this case by merely repeating words drawn from the definition of 'no current work capacity' in s 5 of the Act, or the formulation in s 93 of the Act. I am mindful of the caution sounded by Windeyer J in The Commonwealth v Butler[4] in which his Honour, considering the question whether death resulted from an injury for the purpose of a widow's claim for compensation under the Commonwealth Employees' Compensation Act 1930-1936, said,

But once the simple question is elaborated by attempted para-phrases and explanations of the words "results from", logical and philosophical difficulties emerge however much judges and lawyers may assert that they are eschewing all philosophical consideration of the chain of causation. Attempted explanations of causation and consequence can, I feel, be as unhelpful and unhappy as definitions of reasonable doubt. In the search for some grounds for isolating a particular event from the totality of circumstances preceding a later event, various adjectives, such as "direct", "proximate", "decisive", "immediate", "effective" and "real," have been pressed into service to qualify "cause". From these there is an easy drift to such term as "materially contributing factor". But such formulae do not really dispel the difficulty; and they become especially unsatisfying when death is the alleged consequential event.

...

The words of the statute are more easily applied without exegetical glosses.

22 There are several features of the present case which called for something more than a simple focus on the words of the statute. First, the statute uses different words in different sections, ostensibly to prescribe the same degree of connection between an injury and work capacity. Second, the significance to the Panel's inquiry of the current untreated condition of the left knee to the worker's mobility, and thus capacity to work, was inescapable. Third, there was a generally accepted view by the three reporting medical practitioners that the condition of the left knee was constitutional in its origin. Fourth, it is possible that a pre-existing condition, unconnected to the workplace injury, may be exacerbated by a workplace injury.

23 The critical and final question for the Panel concerned the current work capacity of the worker. The question arose under s 93C of the Act. Weekly payments would not resume unless the worker was assessed as having 'no current work capacity and likely to continue indefinitely to have no current work capacity'. Section 5 of the Act provides,

no current work capacity, in relation to a worker, means a present inability arising from an injury such that the worker is not able to return to work, either in the worker's preinjury employment or in suitable employment;[5]

24 There is a different formulation of the necessary causal link in s 93 of the Act, under which weekly payments are to be made to an injured worker.

If the worker's incapacity for work results from, or is materially contributed to by [a compensable injury]...

The phrase 'results from, or is materially contributed to by' in s 93 of the Act, while a different formulation, is also intended to define the necessary connection between a worker's incapacity and a compensable injury.

25 Thus, the Panel was called upon to express an opinion, in relation to the worker, on her present inability arising from an injury compensable under the Act. It was common ground that the injury to the right knee was a compensable injury.

26 It is important to remember that the phrase in s 5, 'arising from an injury', seeks to relate the workplace injury to incapacity, rather than to another physical condition. In the present case, however, a central issue for the Panel, when considering the relationship between the workplace injury and current work capacity, was to consider the relationship between the injury and the current condition of the left knee. That is, the extent to which that current untreated condition, rather than its origin, arose or resulted from or was materially contributed to by, the injury.

27 While it is unfortunate that there are differing phrases used to establish the required degree of proximity, I do not consider that the legislature intended the words 'arising from the injury' in s 5 to invite a different conclusion than had the words in s 93 been applied. Moreover, the legislative history of workers' compensation in Australia, while sometimes employing different formulations to describe the necessary causal link between injury and incapacity, seems to have been uniformly applied by reference to a commonsense notion of causation that looks for a sufficiently proximate relationship between injury and work capacity.

28 Unfortunately, the assistance given to the Panel in the plaintiff's submissions was unhelpful. The plaintiff referred the Panel to passages from judgments in the High Court in Ward v Corrimal-Belgownie Collieries Ltd,[6] in which the court considered the meaning of the words 'a worker whose injury results in total and permanent disablement'. In their submission to the Panel, the plaintiff emphasised a passage from the judgment of Dixon J in which his Honour said,[7]

When the total disablement of the worker is made up of a partial incapacity due to the injury for which the employer is liable and of a later disability or disabilities due to independent causes, it is, in my opinion, impossible, consistently with [earlier decisions], to hold that the total disablement results from the injury.

29 The plaintiff also referred the Panel to a passage from the judgment of Latham CJ:[8]

In other cases there may already be partial incapacity resulting from an injury, and other causes, quite independent of and not associated with the injury in any way, may afterwards bring about further or total incapacity. In such a case the worker is still entitled to compensation, but it is only the incapacity which is the result of the injury (and not the added incapacity which is the result of other causes) for which there is any liability under the Act. Thus if a man was suffering from an injury consisting in lung disease which produced partial incapacity he would be entitled to compensation in respect of that incapacity. If he subsequently became subject to a form of heart disease which was quite unconnected with his lung disease and by reason thereof became totally incapacitated, he would still be entitled under the Act to payment in respect of the partial incapacity which resulted from the injury, but only to payment for partial incapacity (Harwood v Wyken Colliery Co; Stowell v Ellerman Lines Ltd.) What are called 'natural causes' bring about total incapacity with advancing age. The employer is not liable under the Act for any incapacity resulting from such natural causes. I refer to what Pickford LJ said in Lewis v Wrexham and Acton Collieries Ltd: 'It has been contended, as I understand, that if there be a total incapacity of the workman arising from a partial incapacity as a result of the accident and a partial incapacity arising from something else, the employers must pay for the total incapacity. I certainly do not accept that argument.'

30 While the connecting words under consideration in Ward's case are not identical to those in the definition of 'no current work capacity', or in s 93 of the Act, it would seem that the approach taken by the High Court in Ward's case has been consistently applied in circumstances where, under similar legislation to the Act, an assessment must be made to ascertain a sufficient connection between the workplace injury and incapacity for the purpose of establishing a right to compensation. It is in this context that I have assumed a similar content in the expressions 'arising from'; 'resulting from or materially contributed to by'; and 'arising out of '.

31 I was not directed to any authority in which the relevant test in the Act had been analysed. My own research was unproductive in that regard. The absence of authority concerning the meaning of the words 'arising from', within the definition of 'no current work capacity' in s 5 of the Act, may be explained by the general acceptance of the analysis undertaken in cases such as Ward, and the other cases mentioned below, and by the fact that the relevant inquiry has been removed from the court to Medical Panels, with limited grounds for review.

32 In Government Insurance Office (NSW) v RJ Green & Lloyd Pty Ltd,[9] the employer of a workman sought indemnity from his insurer under a third party insurance policy in respect of damages paid to the injured worker. The employer claimed that the injury to the workman was caused by or arose out of the use of a motor vehicle within the terms of the policy. Unlike the present case, the facts in Government Insurance Office concerned the connection between an event and an injury, rather than an injury and work capacity. Moreover, much of the discussion in that case concerned what was meant by the words 'the use of the motor vehicle'. But the analysis undertaken by the court made reference to the words 'arising out of' as found in s 10 of the Motor Vehicle (Third Party Insurance) Act.

But I have a good deal of difficulty in expressing as a matter of law with any degree of satisfaction and certainty the area which is covered by the expression "caused by or arising out of the use of the motor vehicle", as used in the Act and the policy. The phrase "arising out of" is not here found in the same collocation as it is in workers' compensation legislation, where it is in juxtaposition to a temporal expression. In that sphere the words "arising out of" clearly point to a causal relationship. The words "arising out of" in s 10 of the Act and in the indemnity clause of the policy are not merely, if at all, explicative of the words "caused by"; they are really used in contrast to them; and in the total expression are extensive in their import. Bearing in mind the general purpose of the Act I think the expression "arising out of" must be taken to require a less proximate relationship of the injury to the relevant use of the vehicle than is required to satisfy the words "caused by". It may be that an association of the injury with the use of the vehicle while it cannot be said that that use was casually related to the injury may yet be enough to satisfy the expression "arise out of" as used in the Act and in the policy. [10]

But the question that arises in cases such as this is not answered simply by asking was the vehicle being used. The words "injury caused by or arising out of the use of the vehicle" postulate a causal relationship between the use of the vehicle and the injury. "Caused by" connotes a "direct" or "proximate" relationship of cause and effect. "Arising out of" extends this to a result that is less immediate; but it still carries a sense of consequence. It excludes cases of bodily injury in which the use of the vehicle is a merely casual concomitant, not considered to be, in a relevant causal sense, a contributing factor. But it is not necessary for the solution of this case to go into the wordy jungle that surrounds the lawyer's concept of causation. I have on other occasions sought to explain my understanding of this topic: see in particular The National Insurance Co of New Zealand Ltd v Espagne [1961] HCA 15; (1961) 105 CLR 569, at pp 590-597.

35 Notwithstanding the different statutory and factual context, the foregoing judgments indicate some of the conceptual difficulty mentioned by Windeyer J in The Commonwealth v Butler. The judgments emphasise that connecting expressions such as those under consideration may, having regard to context, call for differing degrees of proximity.

36 What is of assistance, however, is that the words 'arising out of' were considered to involve a less proximate or immediate relationship between cause and effect than the expression 'caused by'. In QBE Insurance v SLE Worldwide[12] White J considered whether a policy issued by the defendant covered a claim by the plaintiff. The inquiry under the relevant insurance policy was whether the liability of an insured was a 'liability arising from and in relation to' certain activities. Having considered the Government Insurance Office case mentioned above, White J said,

In my view, the words 'arising from' denote the need for, at least, an indirect causal relationship ...

37 The difficulty with the passages in Ward's case that were drawn to the attention of the Panel in the plaintiff's submission is that the judicial statements relied upon by the plaintiff were predicated on a consideration of unconnected or independent causes of incapacity. It might have been more helpful to the Panel if its attention had been directed to an earlier passage in the judgment of Latham CJ, in which his Honour said,[13]

In determining whether incapacity results from an injury the law necessarily adopts an idea of causation which, in a sense, isolates the injury as a causative element from other elements which are taken for granted or ignored. If the addition of the injury to other concurrently existing facts brings about the incapacity, then the incapacity is regarded as resulting from the injury, although in fact it results from the injury taken together with the other circumstances.

The legal doctrine may be illustrated by considering the case of a worker who has a condition of heart disease which is not an injury within the meaning of the Act and which has not produced any incapacity. Although the worker has heart disease, he is able to earn full wages, and, as his earning capacity is not diminished, he is suffering from no incapacity within the meaning of the Act (Wicks v Union Steamship Co of New Zealand Ltd). If such a worker then receives an injury within the meaning of the Act and suffers incapacity as the consequence of the injury added to his heart disease, then the incapacity (total or partial as the case may be) in those circumstances results from the injury. The injury is an element which only completes the tale of circumstances which constitutes the cause of the incapacity in the non-legal sense: but in the legal sense it is itself the cause of the incapacity which therefore is said to 'result' from it (See Clover, Clayton & Co Ltd v Hughes; Partridge Jones and John Paton Ltd. v James - cases on 'arising out of the employment'). If an employer employs a man who suffers from some defect, though the defect produces no incapacity, the employer runs the risk that incapacity may more readily result from an injury to such a man than from an injury to a man who does not suffer from any such defect.[14]

38 It seems to me that it would not matter whether the workplace event impacted on a pre-existing condition to bring about incapacity or whether a compensable injury impacted on another latent condition to bring about incapacity. The question is whether there was a sufficient causal link between the workplace injury and the incapacity. Thus, subject to its ultimate determination of that question, it was at least open to the Panel to conclude that notwithstanding a pre-existing constitutional condition of the left knee, unrelated to the workplace injury, the current untreated condition of the left knee arose or resulted from, or was caused or materially contributed to by the injury to the right knee. It must be said at once, however, that the Panel was not required to accept the opinions of Mr Norwsworthy and Dr McColl, but was required to reach its own expert conclusion on such matters.

39 The degree of proximity required to establish the necessary connection between a workplace injury and disability is to be considered in a context where an employer takes the employee as it finds him or her 'with all his predispositions and susceptibilities, whatever they may be'.[15] Paragraph (c) of the definition of 'injury' in s 5 reflects that approach.

40 The High Court has, in a number of cases,[16] endorsed the approach taken by Sir Frederick Jordan CJ in Salisbury v Australian Iron and Steel Ltd,[17] when analysing the circumstances in which a workplace injury and a non-workplace related condition intersect to entitle a worker to compensation. In that case his Honour considered a number of possible scenarios under which a workplace injury, that of itself was not disabling, combined with a pre-existing condition to bring about a compensable incapacity. In a frequently quoted passage, Sir Frederick Jordan said,

It is not necessary that the employment injury should be the sole cause of disability. It is sufficient if it is a contributing cause: Harwood v Wyken Colliery Co. It may be the catalyst which precipitates disability in a medium of disease.

41 In Darling Island Stevedoring and Lighterage Co Ltd v Henkinson[18] Barwick CJ said, after noting his agreement with the 'legal reasoning and conclusions' of Sir Frederick Jordan,

The relevant question in the case of an injury is whether incapacity resulted from it. It is not, as in the case of an action at law based on negligence, what damage has the injured party sustained.

42 It would, of course, be necessary for a medical panel to be mindful of a situation in which the employment injury ceased to produce effects on the non-work related condition. But that eventuality may not arise in the present case if a panel were to accept that the injury to the right knee aggravated a pre-existing condition of the left knee. If the injury to the left knee was consequential and permanent (in the absence of repair) it would have been open to the Panel to conclude that the workplace injury contributed to the current work incapacity of the worker even after the right knee had been repaired. But that of course remains a matter for the individual panel to decide.

43 Returning to the narrow and agreed issue between the parties, the question for determination in this proceeding is the extent to which, if at all, the Panel had wrongly taken into account the condition of the left knee when answering question 4, having regard to its answers to questions 1 and 2. Unfortunately, the issue as formulated had the effect of masking a much deeper problem with the Panel's opinions and reasons. That problem had its origins in the formulation of the questions for the Panel. Nevertheless, the issue as formulated was capable of determination and, even though the outcome may seem somewhat artificial and unsatisfactory, because of uncertainty about the validity of the answers given by the Panel to questions 1 and 2 on which the issue depended, there is no option but to quash the Panel's opinion expressed in its answer to question 4.

44 On that questionable premise, the plaintiff contended that the Panel took into account the left knee condition when concluding that the worker had no current work capacity; and the worker contended that the Panel, in effect, made it clear that it had not done so. These competing contentions depended on a close analysis of the reasons given by the Panel.

45 The Panel gave reasons, also dated 9 January 2012, extending over seven pages. It is not necessary to recite the reasons in full, although some passages were identified by the parties as of particular significance to their respective contentions. These are set out below:[19]

(1) The Panel concluded that the worker is suffering from persisting right knee dysfunction, as a consequence of an aggravation of pre-existing degenerative change in the right knee, which has been treated by a total knee replacement.

...

(2) The Panel concluded that the worker is suffering from a chronic adjustment disorder with mixed anxiety and depressed mood, which arose as a consequence of the injury to the right knee. Her psychiatric condition does not affect her capacity for work.

(3) The Panel took account of the worker's history of an injury to the right knee on 15 November 2004, her subsequent unsuccessful surgical treatment, the persistence of symptoms of pain in the knee since that time and the development of symptoms of a chronic adjustment disorder with mixed anxiety and depressed mood and concluded that the worker's current right knee condition and her chronic adjustment disorder with mixed anxiety and depressed mood are still materially contributed to by the claimed injury to the right knee, but the osteoarthritis of the left knee is constitutional in origin and has not been affected by her right knee condition in any way and therefore does not result from and is not materially contributed to by the claimed injury to the right knee.

(4) The Panel therefore makes no findings about the appropriateness or adequacy of the proposed medical service of left knee replacement.

(5) The Panel concluded that the nature of the worker's physical condition is such that she is not capable of performing her pre-injury duties as a word processing operator.

(6) The Panel took into account all aspects of the definition of 'current work capacity', 'no current work capacity' and 'suitable employment' in the Accident Compensation Act 1985 and in particular, her current age of 53 years (which would not significantly limit her employment options), the nature of her accepted right knee condition (which partially limits her mobility, including her ability to get to and from work) combined with her untreated left knee condition (which severely limits her mobility), her current use of narcotic medications (which affects her concentration), her transferrable skills and previous work experience (which include office skills and supervising up to 19 people), her excellent English language skills (which would not limit her employment options), the absence of a return to work plan, the medical information in the referral material, including the certificates provided by the worker's general practitioner, and her place of residence in outer suburban Melbourne (which would not limit her employment options).

(7) The Panel noted the vocational assessment report from 'Resolve Rehabilitation Services' dated 31 January 2007 supplied with the referral, which contains suggested job options for the worker. Based on its analysis of the criteria for suitable employment set out in the previous paragraph the Panel concluded that the job options of word processor, word processor supervisor, legal secretary, office/administration or general clerk, do not constitute suitable employment for the worker.

(8) The Panel considers that there is no work for which the worker is currently suited and which she could perform on a consistent basis. The Panel concluded therefore that the worker has no current work capacity.

(9) The Panel considers the worker's condition is unlikely to change in the foreseeable future and therefore concluded that she is likely to continue indefinitely to have no current work capacity.

(10) The Panel noted the Certificate of Opinion and Reasons for Opinion of the previous Medical Panel wherein it concluded that the worker had a current work capacity. The current Panel noted that since that Opinion, the worker has had a total right knee replacement and suffers persisting dysfunction of the right knee, that the worker continues to be prescribed narcotic medication which affects her concentration and the worker has developed symptoms and signs of constitutional arthritis of the left knee, all of which have had a significant impact on the worker's work capacity. The current Panel therefore considers there has been a material change in the worker's condition since the previous Panel conducted its examination in April 2008 and has therefore arrived at a different conclusion to the previous Panel regarding the worker's current work capacity.

(11) The Panel noted the medical report of Dr D. J. McColl dated 31 May 2011, wherein he stated that 'Her left knee osteoarthritis has worsened over the years due to her weightbearing through her left leg to protect her work-related osteoarthritic right knee over this time.'

(12) The Panel also noted the medical report of Mr Cameron Norsworthy dated 21 June 2011, wherein he stated that 'The left knee is not related to the patient's employment but has been exacerbated by the work related injury that was sustained by the right knee.'

(13) The Panel arrived at a different conclusion from Dr McColl and Mr Norsworthy for the reasons outlined above.[20]

46 The relevant principles to be applied on an application of this kind are conveniently summarised by Beach J in Bregu v Brydon.[21] They are as follows:

(a) First, it is not enough for a plaintiff to show that the medical panel's reasons for its decision are so expressed as to suggest the possibility that the panel proceeded upon a wrong view of the law. The Court is not entitled to interfere with the decision unless it is satisfied that there was in fact a vitiating error of law.

(b) Secondly, a medical panel's reasons should enable a Court and the parties to understand that the question referred to the panel has been properly considered according to law and that the opinion furnished is founded on the appropriate application of the panel members' medical knowledge and expertise.

(c) Thirdly, the medical panel is an expert tribunal, whose members are chosen for their experience and its findings need to be viewed in that light.

(d) Fourthly, a medical panel's reasons are those of a tribunal, not that of a judicial body, and must be viewed from that perspective.

(e) Fifthly, the reasons of a medical panel are to be read in context, taking into account the background of the case, the material provided and the issues which have to be determined.

(f) Sixthly, the reasons of a medical panel are meant to inform, and over-zealous judicial review is to be eschewed.

(g) Seventhly, the reasons of the medical panel do not need to advert in detail to those matters it has taken into account.

(h) Eighthly, the reasons should give sufficient explanation so as to enable a review thereof by the Supreme Court either under the Administrative Law Act or otherwise by judicial review.

(i) Ninthly, although the medical panel's task is to determine questions of a medical nature, it does not follow that it cannot, or should not, provide the reasons for its determination. Even the most simple of medical questions determined by the panel will nonetheless be based on a process of reasoning and hence enable it to provide reasons. As was said by Callaway JA in Masters v McCubbery:

"There is nothing in the nature even of the simplest medical question that is incompatible with the furnishing of reasons. For example one doctor could sensibly ask another the 'reasons' for his or her diagnosis of a patient's illness."[22]

47 The proper approach of a reviewing court when analysing the reasons of a tribunal has been expressed in numerous ways in the authorities, but for present purposes it is sufficiently summarised by the High Court in Minister for Immigration and Ethnic Affairs v Wu Shan Liang & ors.[23] In a joint judgment, Brennan CJ and Toohey, McHugh, Gummow and Kirby JJ said:

When the Full Court referred to "beneficial construction", it sought to adopt an approach mandated by a long series of cases, the best exemplar of which is Collector of Customs v Pozzolanic Enterprises Pty Ltd. In that case, a Full Court of the Federal Court (Neaves, French and Cooper JJ) collected authorities for various propositions as to the practical restraints on judicial review. It was said that a court should not be "concerned with looseness in the language ... nor with unhappy phrasing" of the reasons of an administrative decision-maker. The court continued:

The reasons for the decision under review are not to be construed minutely and finely with an eye keenly attuned to the perception of error.

These propositions are well settled. They recognise the reality that the reasons of an administrative decision-maker are meant to inform and not to be scrutinised upon over-zealous judicial review by seeking to discern whether some inadequacy may be gleaned from the way in which the reasons are expressed. In the present context, any court reviewing a decision upon refugee status must beware of turning a review of the reasons of the decision-maker upon proper principles into a reconsideration of the merits of the decision. This has been made clear many times in this court. For example, it was said by Brennan J in Attorney-General (NSW) v Quin:

The duty and jurisdiction of the court to review administrative action do not go beyond the declaration and enforcing of the law which determines the limits and governs the exercise of the repository's power. If, in so doing, the court avoids administrative injustice or error, so be it; but the court has no jurisdiction simply to cure administrative injustice or error. The merits of administrative action, to the extent that they can be distinguished from legality, are for the repository of the relevant power and, subject to political control, for the repository alone.

48 The plaintiff submitted that once the Panel had concluded that the worker was suffering from constitutional osteoarthritis in the left knee that was not relevant to any injury to the right knee [answer to question 1]; and that the osteoarthritis of the left knee did not result from and was not materially contributed to by the injury to the right knee [answer to question 2]; it was plain from the reasons that the Panel took account of the significant incapacitating consequences of the left knee condition in arriving at its answer to question 4. The plaintiff argued that the Panel's answer to question 4 was explicable on no basis other than that it erroneously had regard to an incapacitating condition not relevantly connected with the workplace injury. Accordingly, the plaintiff submitted, the Panel had erred by taking that condition into account when deciding that the worker had no current work capacity. The plaintiff went further and contended that the Panel either did not take account of its submission on that point or that in view of those submissions did not explain how it arrived at its answer to question 4.

49 The worker's contentions may be conveniently summarised by the following propositions:

(1) The Panel only took the left knee condition into account as a background factor that had some bearing on the worker's mobility. However, when reaching its ultimate conclusion as to suitable employment, it could not be said that the Panel had relied solely, or indeed heavily, on that particular consideration.

(2) The Panel did not state in its reasons that the left knee condition limited the worker's ability to get to and from work, in contrast to the specific finding in relation to the effect on mobility of the right knee condition.

(3) There was nothing to suggest that the Panel would have concluded that Ms Darbyshire had a current work capacity but for her left knee condition.

(4) There was no evidence that the Panel failed to take relevant considerations into account.

(5) There was no reason to suppose that the Panel did not have regard to the plaintiff's submissions.

50 The Panel adopted an emphatic style in its reasons by concluding that 'the osteoarthritis of the left knee is constitutional in origin and has not been affected by (the) right knee condition in any way and therefore does not result from and is not materially contributed to by the claimed injury to the right knee'.[24] While ambiguous, in the sense that it is not clear whether the Panel was concerned only with the 'origin' of the left knee or facts that contributed to its current condition, the Panel later noted its disagreement with parts of the reports by Dr Norsworthy and Dr McColl, in which they concluded that there was a connection between the workplace injury and the current condition of the left knee. The lack of clarity in the position of the Panel is perhaps not surprising in the absence of any guidance on the correct approach to an assessment of the proximity between the workplace injury and the current work capacity for the purpose of s 93C of the Act, and in the formulation of questions 1 and 2.

51 The worker relied on the same passage to indicate that the Panel did not have regard to the condition of the left knee in the formation of its opinion in response to question 4. The worker seemed to accept that, by its answers to questions 1 and 2, the Panel had excluded any connection between the current condition of her left knee and the workplace injury.

52 While such a concession by the worker seemed counterintuitive, by accepting the answers to questions 1 and 2, the worker's case overlooked the possibility that the current condition of the left knee might properly have been taken into account if the Panel was satisfied that, notwithstanding the 'origin' of the condition, the current condition might have been contributed to by the injury to the right knee, as found by Mr Norsworthy and Dr McColl.

53 In any event, the worker argued that when read together with the Panel's conclusion that 'the worker's condition is unlikely to change in the foreseeable future',[25] it was unlikely that the Panel had regard to the left knee at all because, with surgery, she might have achieved a working capacity after only a few weeks.

54 The worker argued that the reports of Mr Norsworthy and Dr McColl indicated the possibility of a very significant change in her capacity for employment following surgery to her left knee. It was against that background, so the worker argued, the Panel concluded that the worker's condition was unlikely to change.[26] Thus, argued the worker, the Panel must be taken to have disregarded the left knee because, had it done otherwise, it would have acknowledged the possibility of change following surgery.

55 Thus, the worker contended, the Panel approached question 4 correctly by ignoring the condition of the left knee. Were it otherwise, she argued, the Panel's emphatic rejection of any material contribution by the workplace injury made no sense. The worker also pointed out that the Panel made express reference to the statutory definitions, including 'no current work capacity'.

56 The plaintiff contended that the Panel lost sight of its duty to confine its assessment of 'no current work capacity' to an inability arising from the work related injury, sliding into a consideration of the worker's overall physical health and ability to work and the likelihood of that changing in the foreseeable future. From the plaintiff's perspective, the answers to questions 1 and 2 were plainly correct, highlighting the slide, because the Panel had apparently rejected a contributing connection between the workplace injury and the condition of the left knee that was so critical to the Panel's assessment of the worker's lack of mobility and capacity to work.

57 The plaintiff submitted that the slide commenced almost immediately after the Panel's emphatic statement to the effect that the condition of the left knee did not result from and was not contributed to by the workplace injury. After concluding that 'the nature of the worker's physical condition is such that she is not capable of performing her pre-injury duties as a word processing operator',[27] the Panel set out the factors that it 'took into account',[28] which plainly included 'the nature of her accepted right knee condition (which partially limits her mobility, including her ability to get to and from work) combined with her untreated left knee condition (which severely limits her mobility) ...'[29]

58 The plaintiff further submitted that having taken into account the left knee condition, as one which severely limited the worker's mobility, the Panel concluded that there was no work for which she was currently suited and which she could perform on a consistent basis;[30] that the worker had 'no current work capacity'; and that 'the worker's condition is unlikely to change in the foreseeable future ...'[31] The plaintiff submitted that these passages could be explained on no logical basis other than that the Panel had taken into account the severely limiting condition of the left knee. I agree.

59 The plaintiff submitted that the remaining passages in the reasons reinforced the Panel's error. For example, when considering the change that had occurred since the previous Medical Panel had expressed its opinions on 5 May 2008, the Panel specifically mentioned 'signs of constitutional arthritis of the left knee' among factors 'all of which have had a significant impact on the worker's work capacity'.[32]

60 Finally, the plaintiff submitted that, contrary to the worker's contention, the reference, in the concluding paragraphs,[33] to the reports of Dr McColl and Mr Norsworthy, should not be taken as an indication that the Panel categorically rejected the relevance and significance of the left knee condition in the formation of its opinion in response to question 4 as the worker contended.

61 It is difficult to know precisely why the Panel chose to make reference to the particular passages from those reports, unless to emphasise a point of difference concerning the connection between the work related injury and the condition of the left knee. Dr McColl and Mr Norsworthy thought there was a connection, while it would appear the Panel did not. But, it remains uncertain as to precisely what it was that the various practitioners thought was connected.

62 The Panel's view that the worker's condition 'is unlikely to change in the foreseeable future'[34] must be premised on the absence of left knee surgery. The conclusion 'that she is likely to continue indefinitely to have no current work capacity' seems explicable only be reference to the untreated condition of the left knee. Thus, contrary to the worker's submission, this is another indicator that the Panel took account of the worker's overall physical condition when determining her capacity for work.

63 It was, of course, theoretically, possible for the Panel to arrive at its opinion, stated in response to question 4, by accepting the necessary connection between the workplace injury and the current condition of the worker's left knee. But such an opinion, if so formed, was not explained and would have been inconsistent with the construction that the plaintiff and the worker accept should be placed on the Panel's answers to questions 1 and 2. If those answers are to be taken to mean what the plaintiff and the worker contend, they stand in stark contrast with the relevance attributed by the Panel to the current condition of the worker's left knee when assessing her mobility and current capacity for work.

64 The mere fact that the Panel did not mention the plaintiff's submission on this point is of no consequence. What seems plain from the reasons is that the Panel did take account of the whole of the 'worker's physical condition', including her unrepaired left knee condition, to determine her current work capacity. In my view there is no other way to fairly interpret the reasons.

65 Notwithstanding my unease about the formulation of questions 1 and 2, and the Panel's answers, the construction of those answers accepted by the plaintiff and the worker demonstrated that the Panel had regard to a condition that it had concluded was unrelated to the workplace injury. On that basis the Panel misdirected itself by taking into account the worker's current left knee condition when assessing her current work capacity. In so doing the Panel must be taken to have made an error of law.

66 In my opinion an order merely setting aside the opinion expressed as an answer to question 4 would ignore the underlying difficulty with the Panel's answers to questions 1 and 2, and the course of reasoning that revealed the error of law. Question 4 should not, in my view, be referred for re-consideration by the same panel. Moreover, it would be unreasonable to expect a new medical panel to revisit only one question. The better course is to refer all questions to a new panel so that it can start with a 'clean slate'. The parties might also give consideration to the reformulation of questions 1 and 2 which in my view are at least ambiguous, and likely to lead to further error if uncorrected.

[4] [1958] HCA 56; (1958) 102 CLR 465, 479-480.

[6] [1938] HCA 70; (1938) 61 CLR 120

[7] [1938] HCA 70; (1938) 61 CLR 120, 144.

[8] [1938] HCA 70; (1938) 61 CLR 120, 130-131, citations omitted.

[9] [1966] HCA 6; (1966) 114 CLR 437.

[10] [1966] HCA 6; (1966) 114 CLR 437, 442.

[11] [1966] HCA 6; (1966) 114 CLR 437, 447.

[12] (2005) NSWSC 776 [27].

[13] Ward v Corrimal-Belgownie Collieries Ltd [1938] HCA 70; (1938) 61 CLR 120, 129-130; citations omitted. Ward's case, and the passage to which I have referred above, were applied by Zeeman J in Osborn v Est Hotel Enterprises Pty Ltd. (1992) 1 Tas R 318 in which his Honour referred to Pickersgill v Freightbases Pty Ltd, [1983] 3 NSWLR 117, 118, which in turn applied Commonwealth v Butler [1958] HCA 56; (1958) 102 CLR 465, 479-480.

[15] Comcare v Amorebieta (1996) 66 FCR 83, 95.

[16] Examples include Darling Island Stevedoring and Lighterage Co Ltd v Henkinson [1967] HCA 10; (1967) 117 CLR 19; Calman v Commissioner of Police [1999] HCA 60; 167 ALR 91.

[17] (1943) 44 SR(NSW) 157, 162.

[18] [1967] HCA 10; (1967) 117 CLR 19.

[19] Paragraph numbers have been added to facilitate cross referencing in these reasons.

[21] [2010] VSC 417, [17].

[23] [1996] HCA 6; (1996) 185 CLR 259, 271-2.