Reported Decision : 67 NSWLR 372 New South Wales Court of Appeal CITATION: CAMPBELLTOWN CITY COUNCIL v VEGAN & ORS [2006] NSWCA 284 This decision has been amended. Please see the end of the judgment for a list of the amendments. HEARING DATE(S): 21 February 2006 JUDGMENT DATE: 25 October 2006 JUDGMENT OF: Handley JA at 1; McColl JA at 33; Basten JA at 34 DECISION: (1) Appeal allowed; (2) Subject to any objection being taken by the Registrar within 14 days, join the Registrar, Workers Compensation Commission, as a respondent to the appeal; (3) Set aside the order made in the Common Law Division dismissing the proceedings and in lieu thereof; (a) set aside the certificate issued by the Appeal Panel in matter number WCC 5067-2002, and; (b) remit the matter to the Registrar for referral to an Appeal Panel constituted under s 328 of the Workplace Injury Act for determination according to law; (4) Pursuant to the condition imposed on the grant of leave to appeal, order the Appellant to pay Mrs Vegan's costs of the appeal; (5) Direct the Authority within 2 days to provide the Registrar with a copy of these orders and reasons for judgment. CATCHWORDS: WORKERS COMPENSATION – whether the Appeal Panel under the Workplace Injury Management and Workers Compensation Act 1998 (NSW) was obliged to give reasons for its decision – medical assessment by the Appeal Panel on review of an approved medical specialist – different findings on percentage of permanent loss – whether the reasons given were adequate – consequence of breach of obligation to give reasons. - ADMINISTRATIVE LAW – statutory review – express obligation of primary decision-maker to give reasons – whether implied duty of review body to give reasons – consequence of breach. - ADMINISTRATIVE LAW – statutory review – proper parties to judicial review. Acts Interpretation Act 1901 (Cth), s 25D Administrative Decisions (Judicial Review) Act 1977 (Cth), s 13 Compensation Court Repeal Act 2002 (NSW), s 4 Judiciary Act 1903 (Cth), s 39 LEGISLATION CITED: Supreme Court Act 1970 (NSW), ss 65, 69 Supreme Court Rules 1970 (NSW), Part 8, r 2, r 8; Part 51, r 9 Trade Practices Act 1974 (Cth), s 86 Workers Compensation Act 1987 (NSW), ss 66, 67, cl 4 of Part 18C of Schedule 6 Workers Compensation Regulation 2003 (NSW), Part 23, cls 223, 224 Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 4, 14, 22, 23, 106, 250, 294, 319, 321, 322, 323, 325, 326, 327, 328, 329, 350, 353 Allesch v Maunz (2000) 203 CLR 172 Anderson Stuart v Treleaven (2000) 49 NSWLR 88 Attorney-General (NSW) v Kennedy Miller Television Pty Ltd (1998) 43 NSWLR 729 Attorney General v Sillem (1864) 10 HLC 704, 724 [11 ER 1200, 1209] Australian Postal Commission v Dao (No. 2) (1986) 6 NSWLR 497 Australian Securities Commission v Ampolex Ltd (1995) 38 NSWLR 504 Australian Securities and Investments Commission v Farley (2001) 51 NSWLR 494 Avon Downs Pty Ltd v Federal Commissioner of Taxation (1949) 78 CLR 353 Brandy v Human Rights and Equal Opportunity Commission (1995) 183 CLR 245 Campbelltown City Council v Vegan [2004] NSWSC 1129 Carlson v King (1947) 64 WN (NSW) 65 Clifford and Sullivan [1921] 2 AC 570 Commissioner for ACT Revenue v Alphaone Pty Ltd (1994) 49 FCR 576 The Commonwealth of Australia v Bank of New South Wales [1950] AC 235 Craig v South Australia (1995) 184 CLR 163 Darling Casino Ltd v NSW Casino Control Authority (1997) 191 CLR 602 Deputy Commissioner of Taxation v Richard Walter Pty Ltd (1995) 183 CLR 168 Hanna v Department of Immigration, Multicultural and Indigenous Affairs [2004] NSWCA 275 Hargrave v Slater (2003) 113 A Crim R 371 Housing Commission of NSW v Tatmar Pastoral Co Pty Ltd [1983] 3 NSWLR 378 Houssein v Under Secretary of Industrial Relations & Technology (NSW) (1982) 148 CLR 88 Luton v Lessels (2002) 210 CLR 333 Mifsud v Campbell (1991) 21 NSWLR 725 CASES CITED: Muin v Refugee Review Tribunal (2002) 76 ALJR 966 North Broken Hill Ltd v Tumes (1999) 18 NSWCCR 412 Orellana-Fuentes v Standard Knitting Mills Pty Ltd (2003) 57 NSWLR 282 Oshlack v Richmond River Council (1998) 193 CLR 72 Osmond v Public Service Board of New South Wales [1984] 3 NSWLR 447 Parramatta CC v Palmyra Freeholds Pty Ltd [1974] 2 NSWLR 83 Pettitt v Dunkley [1971] 1 NSWLR 376 Plaintiff S157/2002 v Commonwealth (2003) 211 CLR 476 Public Service Board of New South Wales v Osmond (1986) 159 CLR 656 The Queen v Australian Broadcasting Tribunal; Ex parte Hardiman (1980) 144 CLR 13 R v Secretary of State for the Home Department; Ex parte Doody [1994] 1 AC 531 Re Minister for Immigration and Multicultural Affairs; Ex parte Miah (2001) 206 CLR 57 Re Minister for Immigration and Multicultural and Indigenous Affairs; Ex parte Palme (2003) 216 CLR 212 Re Ruddock; Ex parte Reyes (2000) 75 ALJR 465 Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission of NSW [2005] NSWSC 1260 SAAP v Minister for Immigration and Multicultural and Indigenous Affairs (2005) 79 ALJR 1009 Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247 Taylor v Public Service Board [1975] 2 NSWLR 278; (1976) 137 CLR 208 Trust Company of Australia Ltd v Skiwing Pty Ltd [2006] NSWCA 185 Turnbull v New South Wales Medical Board [1976] 2 NSWLR 281 Vetter v Lake Macquarie City Council (2001) 202 CLR 439 Witness v Marsden (2000) 49 NSWLR 429 Xuereb v Viola (1989) 18 NSWLR 453 York v General Medical Assessment Tribunal (2003) 2 Qd R 104 Campbelltown City Council - Appellant PARTIES: Margaret Theresa Vegan - First Respondent Brydget Barker-Hudson, Dr D Dixon and Dr J Ellis constituting the Medical Appeal Panel of the Workers Compensation Commission of NSW - Second Respondent Workcover Authority of New South Wales - Third Respondent FILE NUMBER(S): CA 41149/04 Mr J Simpkins SC - Appellant COUNSEL: Mr M J Perry - First Respondent Ms M Allars - Third Respondent Bartier Perry - Appellant SOLICITORS: Bryan Gorman & Co, Campbeltown - First Respondent Crown Solicitors Office, Second and Third Respondents LOWER COURT JURISDICTION: Supreme Court LOWER COURT FILE NUMBER(S): SC 30022/04 LOWER COURT JUDICIAL OFFICER: Wood CJ at CL LOWER COURT DATE OF DECISION: 25 November 2004; revised 14 December 2004 LOWER COURT MEDIUM NEUTRAL CITATION: Campbelltown City Council v Vegan [2004] NSWSC 1129 IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 41149/04 SC 30022/04 HANDLEY JA McCOLL JA BASTEN JA CAMPBELLTOWN CITY COUNCIL v VEGAN Mrs Vegan, employed by the Appellant, Campbelltown City Council, was injured in the course of her employment as a child-care worker. She was assessed by an approved medical specialist, appointed under the Workplace Injury Management and Workers Compensation Act 1998 (NSW) and provided with a medical assessment certificate. An Appeal Panel revoked the certificate and issued a new certificate which assessed her percentage of permanent loss at a higher rate. The Council brought proceedings for judicial review of the Appeal Panel's decision which Wood CJ at CL dismissed. The Council appealed against this decision. The issues for determination by the Court of Appeal were: (i) what parties should have been joined in the proceedings; (ii) whether the Appeal Panel had obligation to give reasons for its decision, and; (iii) whether the reasons given by the Appeal Panel were adequate and the consequence of breaching its obligation to give reasons. Held in relation to (i): Per Basten JA (Handley & McColl JJA agreeing) 1. In proceedings to review the decision of an inferior tribunal, absent some statutory provision to the contrary, it will usually be necessary to join the tribunal. However, it will usually be appropriate to identify the tribunal by its statutory designation, so that persons who may constitute the tribunal from time to time, if reconstituted, will be bound: at [55]. SAAP v Minister for Immigration and Multicultural and Indigenous Affairs (2005) 79 ALJR 1009; Re Ruddock; Ex parte Reyes (2000) 75 ALJR 465, applied. 2. Bodies responsible for the administration of a legislative scheme may appear in court proceedings involving the operation of the scheme in order to assist a court in relation to matters of powers and procedures. The WorkCover Authority had no legal interest in the proceedings below, therefore there was no obligation to join it to the appeal, nor was it appropriate to do so. Its role should be confined to that of an amicus curiae: at [58]–[64]. Held in relation to (ii): By Handley JA (McColl JA agreeing) 1. A duty to give proper reasons is a legal incident of the judicial process, but is not normally a legal incident of administrative decision-making, nor of expert assessment pursuant to law such as that provided for in the Workplace Injury Act: at [20]. Public Service Board of New South Wales v Osmond (1986) 159 CLR 656; Carlson v King (1947) 54 WN (NSW) 65; Pettitt v Dunkley [1971] 1 NSWLR 376, applied. 2. A statement of reasons may be necessary to enable a party to exercise a right of appeal or such rights as he or she may have to contest the decision. This reasoning applies where there is an appeal from an administrative decision maker to a panel or from an expert to a panel of experts: at [24] Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247, applied. 3. Since the approved medical specialist has a duty to give proper reasons, the Appeal Panel, in correcting any error, should do what the medical specialist should have done by making the right decision and giving proper reasons for it. The Appeal Panel's reasons would facilitate a court or the Commission properly to exercise the power under s 329(1)(b) of the Workplace Injury Act to order a further medical assessment: at [26]–[31], and at [114]–[116], Basten JA. Per Basten JA (Handley & McColl JJA agreeing): 4. There is no express statutory obligation in ss 325, 326 and 327 of the Workplace Injury Act, to give reasons: at [100]–[101]. 5. The justification for an obligation to give reasons is derived from the right of appeal granted in relation to an exercise of judicial power. Reliance is also placed on the principle that "justice must not only be done but must be seen to be done": at [105] Public Service Board of New South Wales v Osmond (1986) 159 CLR 656; Osmond v Public Service Board of New South Wales [1984] 3 NSWLR 447; Pettitt v Dunkley [1971] 1 NSWLR 376, Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247; Housing Commission of NSW v Tatmar Pastoral Co Pty Ltd [1983] 3 NSWLR 378, applied. 6. The difficulties which arise when pursuing judicial review in the absence of reasons cannot, by themselves, provide a justification for implying an obligation to give reasons. The classification of the functions of the tribunal as administrative or judicial therefore remains important: at [106]. Whether the Appeal Panel is exercising judicial functions is a question of statutory construction: at [108]. Orellana-Fuentes v Standard Knitting Mills Pty Ltd (2003) 57 NSWLR 282; Trust Company of Australia Ltd v Skiwing Pty Ltd [2006] NSWCA 185; Australian Postal Commission v Dao (No.2) (1986) 6 NSWLR 497, considered. 7. The assessment of permanent impairment undertaken by the Appeal Panel involved the application of a statutory test, by which legal rights as between an employee and employer are determined. Accordingly, it is an exercise in the nature of a judicial function, whatever the precise name or status of the Appeal Panel itself: at [109]. Brandy v Human Rights and Equal Opportunity Commission (1995) 183 CLR 245; Luton v Lessels (2002) 210 CLR 333; Trust Company of Australia Ltd v Skiwing Pty Ltd [2006] NSWCA 185; applied. 8. The Appeal Panel was subject to an implied statutory obligation to give reasons: at [117]. Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247, applied; York v General Medical Assessment Tribunal (2003) 2 Qd R 104, distinguished. Held in relation to (iii): Per Basten JA (Handley & McColl JJA agreeing) 1. Where more than one conclusion is open as to the existence, nature and extent of any physical impairment, it will be necessary for the Panel to give some explanation of its preference for one conclusion over another, especially where the medical members of a Panel have made their own assessment and have come to a different conclusion from that reached by other medical practitioners. To fulfil a minimum legal standard, the reasons need not be extensive or provide detailed explanation of the criteria applied by medical specialists in reaching a professional judgment: at [121]–[122]. Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247, applied. 2. The present reasons demonstrate no attempt to explain significant departures from the assessment by Dr Adler, nor any attempt to explain the errors which were said to exist in his reasons and findings. It is clear the reasons were manifestly deficient and did not constitute compliance with the minimum requirement of the obligation to give reasons: at [129]. 3. A failure to give reasons constitutes an error of law on the face of the record and the decision of the Panel may be set aside under s 69 of the Supreme Court Act 1970 (NSW): at [130]. IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 41149/04 SC 30022/04 HANDLEY JA McCOLL JA BASTEN JA CAMPBELLTOWN CITY COUNCIL v VEGAN Judgment 1 HANDLEY JA: In this appeal I have had the benefit of reading the reasons for judgment of Basten JA in draft. He has set out the facts, the history of the proceedings, and the legislation. I agree with the orders he has proposed, and with much of his reasoning, but prefer to express brief reasons of my own. 2 On 9 July 2003 Dr Adler, an approved medical specialist appointed under the Workplace Injury Management and Workers Compensation Act 1998 (the Act) provided a medical assessment certificate under s 325 of the Act in which he assessed the worker's permanent percentage loss at 5% of her neck, 2% of her back, and 8% of her right arm at or above the elbow. On 25 July the worker's solicitors lodged an appeal under s 327(1) against that assessment. 3 An Appeal Panel comprising two approved medical specialists and an arbitrator were appointed and on 11 December 2003 the Panel revoked the certificate given by Dr Adler and issued a new certificate which assessed the worker's percentage of permanent loss at 10% of her neck, 5% of her back, and 10% of her right arm at or above the elbow, and 8% of her left arm at or above the elbow. 4 On 15 December the Council's solicitors wrote to the Registrar complaining that the reasons of the Appeal Panel were "brief and minimal" and sought some clarifications and an opportunity to be heard. On 24 December the Registrar replied stating that the determination of the Appeal Panel was final and there was no provision for the Commission or the Panel to review the certificate or address the issues that had been raised. 5 The Council commenced proceedings for judicial review of the decision of the Appeal Panel which were heard by Wood CJ at CL and dismissed. The Council has appealed by leave granted by this Court. 6 I agree with Basten JA that the reasons provided by the Appeal Panel for revoking the certificate given by Dr Adler and issuing a new certificate were so inadequate as to vitiate the certificate if there was an obligation to give proper reasons. The only question is whether it had such an obligation and, if so, the basis for it. 7 The right of appeal to an Appeal Panel is conferred by s 327(1). The permissible grounds for appeal are those referred to in s 327(3) as follows: "(a) deterioration of the worker's condition that results in an increase in the degree of permanent impairment, (b) availability of additional relevant information (being evidence that was not available to the appellant before the medical assessment appealed against or that could not reasonably have been obtained by the appellant before that medical assessment), (c) the assessment was made on the basis of incorrect criteria, (d) the medical assessment certificate contains a demonstrable error." 8 An appeal does not proceed to an Appeal Panel unless it appears to the Registrar that at least one of the grounds for appeal "exists", which I take to mean that the ground is, on its face, valid and apparently credible (s327(5)). If the appeal is on a ground referred to in s 327(3)(a) or (b) the Registrar may refer the matter for further assessment under s 329 as an alternative to an appeal. 9 The appeal is to be by way of "review" of the original assessment (s328(2)) but fresh or additional evidence cannot be given unless it was not available to the appellant or could not reasonably have been obtained before the assessment. 10 Section 328(5) provides that the Appeal Panel may confirm the certificate of assessment appealed against "or may revoke that certificate and issue a new certificate as to the matters concerned. Section 326 applies to any such new certificate". Section 326 provides: "(1) An assessment certified in a medical assessment certificate … under this Part is conclusively presumed to be correct as to the following matters in any proceedings before a court or the Commission with which the certificate is concerned: (a) the degree of permanent impairment of the worker as a result of an injury, (b) whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality, (c) the nature and extent of loss of hearing suffered by a worker, (d) whether impairment is permanent, (e) whether the degree of permanent impairment is fully ascertainable. (2) As to any other matter, the assessment certified is evidence (but not conclusive evidence) in any such proceedings." 11 Section 329(1) provides that a matter referred to assessment may be referred again on one or more further occasions but only by "(a) the Registrar as an alternative to an appeal … or (b) by a court or the Commission". 12 Section 325(2) provides: "(2) A medical assessment certificate is to be in a form approved by the Registrar and is to: (a) set out details of the matters referred for assessment, and (b) certify as to the approved medical specialist's assessment with respect to those matters, and (c) set out the approved medical specialist's reasons for that assessment, and (d) set out the facts on which that assessment is based." 13 Thus an argument is available that Parliament, having expressly directed that one of the sections (s 326 – conclusive effect) that apply to a medical assessment certificate of an approved medical specialist, should apply to a certificate of an Appeal Panel, but not another (s 325 – contents of certificate) the latter does not apply to such a certificate. 14 This would invoke the maxim that an express provision excludes an implied one (expressio unius est exclusio alterius). However in Houssein v Under Secretary of Industrial Relations & Technology (NSW) (1982) 148 CLR 88, 94 the Court said: "That maxim [expressio unius] must always be applied with care, for it is not of universal application and applies only when the intention it expresses is discoverable upon the face of the instrument … It is a valuable servant but a dangerous master." 15 Section 327 authorises an appeal from the assessment of a medical expert to a panel including other medical experts. The nature of an appeal, in the strict sense, to a superior court is well established. In Attorney General v Sillem (1864) 10 HLC 704, 724 [11 ER 1200, 1209] Lord Westbury LC said: "An appeal is the right of entering a superior Court, and invoking its aid and interposition to redress the error of the Court below." 16 In The Commonwealth of Australia v Bank of New South Wales [1950] AC 235, 294 the Privy Council added an important qualification: "… an appeal is the formal proceeding by which a unsuccessful party seeks to have the formal order of a court set aside or varied in his favour by an appellate court." 17 Administrative appeals were unknown, or relatively unknown, in Australia and Britain in 1950, but are now common in both jurisdictions. Parliament by providing for such appeals must be taken to have intended that an appeal to a superior administrative body should be similar to an appeal to a superior court. 18 Since an appeal is a means of redressing or correcting an error of the primary decision maker a successful appeal should produce the correct decision, that is the decision the original decision maker should have made. It is therefore an inherent feature of the appellate process that the appellate decision maker exercises, within the limits of the right of appeal, the jurisdiction or power of the original decision maker. Hence in Parramatta CC v Palmyra Freeholds Pty Ltd [1974] 2 NSWLR 83, 87 Reynolds JA, giving the principal judgment of the Court, said: "It may be stated as a general proposition that an appellate tribunal is not, in the absence of express provision, invested with power to do that which the subordinate tribunal could not have done." 19 So called appeals may take a number of different forms which were identified by Glass JA in Turnbull v New South Wales Medical Board [1976] 2 NSWLR 281, 297-8, although judicial review and motions for a new trial based on fraud or fresh evidence invoke an exercise of original jurisdiction. If the appellate tribunal, like the Appeal Panel, is entitled to receive additional evidence its jurisdiction will be original and not strictly appellate when such evidence is acted on. 20 A duty to give proper reasons is a legal incident of the judicial process: Public Service Board of New South Wales v Osmond (1986) 159 CLR 656, 667, but is not normally a legal incident of administrative decision making (ibid), nor is it a legal incident of expert assessment pursuant to law such as that provided for in the Act. 21 A duty to give proper reasons is also implied where there is an appeal to a superior court. In Carlson v King (1947) 64 WN (NSW) 65, 66 Jordan CJ said: "It has long been established that it is the duty of a Court of first instance, from which an appeal lies to a higher Court, to make, or cause to be made, a note of everything necessary to enable the case to be laid properly and sufficiently before the appellate Court if there should be an appeal. This includes not only the evidence, and the decision arrived at, but also the reasons for arriving at the decision." 22 This passage was cited with approval in Pettitt v Dunkley [1971] 1 NSWLR 376, 381, 387. At 381 Asprey JA said: "The rights of appeal … are statutory rights granted by the legislature to the parties … and the failure of a trial judge in the appropriate case to state his findings and reasons amounts, in my view, to an encroachment upon those rights. The omission of the trial judge makes it impossible for an appellate Court to give effect to those rights … and so carry out its own appellate functions." 23 In Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247, 270 Mahoney JA referred to this decision and said: "Thus, the statement of reasons may be necessary to enable a party to exercise his right of appeal or such other rights as he may have to contest the decision : this is one of the conventional functions of the requirement" (emphasis supplied). 24 In my judgment this reasoning applies where there is an appeal from an administrative decision maker to a panel or from an expert to a panel of experts. Hence an approved medical specialist such as Dr Adler would in any event have had an implied duty to give proper reasons. 25 The identification of an implied duty to give proper reasons is an exercise in statutory construction but the court's approach is not a mechanical one. As Deane J said in Public Service Board of NSW v Osmond (1986) 159 CLR 656, 676: "… the courts should be less reluctant than they would have been in times past to discern in statutory provisions a legislative intent that the particular decision-maker should be under a duty to give reasons." 26 The Appeal Panel does not have an express duty to give proper reasons, but in my judgment there are two bases for finding an implied duty. The first depends on the power and duty of the Appeal Panel to correct error. Since the approved medical specialist has a duty to give proper reasons the Appeal Panel, in correcting any error, should do what the medical specialist should have done, that is make the right decision and give proper reasons for it. 27 A cumulative basis for finding an implied duty to give reasons is that they would enable the court or the Commission to properly exercise the power under s 329(1)(b) to order a further medical assessment. 28 The existing assessment will be binding but the power to order a further assessment is available where other evidence suggests that the assessment was wrong, or the worker's condition has changed. The power is analogous to that of an appellate court to order a new trial. 29 The exercise of this power will be facilitated by the existence of reasons. Its exercise will be hindered where the certificate is that of an Appeal Panel unless it has given reasons for its assessment. 30 The right of a disaffected party to persuade the court or the Commission that an otherwise conclusive certificate of an Appeal Panel should not be accepted without a further assessment, constitutes the only right of the disaffected party, other than judicial review, "to contest the decision" in that certificate, to borrow the language of Mahoney JA: para [23]. 31 In my judgment therefore the Appeal Panel was bound to give proper reasons for its assessment and its failure to do so constituted legal error on the face of the certificate. 32 The orders proposed by Basten JA should be made. 33 McCOLL JA: I have had the privilege of reading Basten JA's judgment in draft. I agree with the orders he proposes and generally with his reasons. I also agree with Handley JA's reasons. 34 BASTEN JA: Where a worker is injured in the course of his or her employment and a dispute arises as to the extent of the injury, as between a claimant for compensation and the employer, the dispute may be referred to an approved medical specialist for assessment: see Workplace Injury Management and Workers Compensation Act 1998 (NSW) ("the Workplace Injury Act"), Chapter 7, Part 7. In such a case, the matters referred for assessment are to be dealt with by the specialist in a "medical assessment certificate". An appeal is provided, by way of "review" to an Appeal Panel. The present proceeding concerned the nature of such an appeal, the scope of the obligation of the Appeal Panel to give reasons for its decision and the consequences of breach of any obligation to give reasons. Background 35 In 2001, Mrs Vegan was a childcare worker employed by the Campbelltown City Council at the Minto Childcare Centre. On 29 August 2001 whilst sitting on the floor nursing a distressed child, she was thrown backwards against the wall by the child's movements. Although not aware of any specific injury at the time, she developed a serious pain in her back and right shoulder, by the next morning. In a 'report of injury' form completed the following day, she indicated she had a "strained right shoulder", the area affected being identified as the "right shoulder region". 36 Over the course of the following year, Mrs Vegan received medical treatment and also continued with light duties, when they were available. On 25 July 2002 she obtained a report from Dr Neil Berry, who noted that she now complained of "bilateral shoulder pain, neck pain and interscapular pain". His examination of the cervical spine indicated that the patient was "tender over the superior and posterior aspects of both shoulders". On 20 August 2002, Mrs Vegan's solicitor sent a copy of the report to the Council, with a claim pursuant to ss 66 and 67 of the Workers Compensation Act 1987 (NSW) seeking a payment for a degree of permanent impairment, which was said to exceed 10%. 37 On 1 November 2002, the Council replied noting that Mrs Vegan had been examined by its own consultant orthopaedic surgeon who had expressed the view that her condition "has not stabilised" and would not do so for a further six months to one year. In December 2002 Mrs Vegan filed an application with the Workers Compensation Commission seeking to have the dispute resolved by an approved medical specialist. In due course Dr Robert Adler, a specialist in rehabilitation medicine at Westmead, was appointed. He examined Mrs Vegan on 1 May 2003 and provided a "medical assessment certificate of permanent impairment", pursuant to s 325 of the Workplace Injury Act, on a date which was agreed between the parties to be 9 July 2003. Dr Adler assessed a total permanent impairment as follows: Body Part Total % of permanent loss … Neck … 5% Back … 2% Right arm at or above the elbow … 8% Left arm at or above the elbow … 0% 38 The table in which Dr Adler provided these figures included separate columns permitting an assessment in relation to specific injury, a calculation on account of pre-existing injury or abnormality, and a total impairment, which would have been the balance of the first less the second. In the case of Mrs Vegan, there was no pre-existing injury or abnormality, but in translating his assessment of the impairment of her back, having assessed a 2% impairment and 0% for pre-existing injury, he then incorrectly entered 0% for the total permanent impairment of her back attributable to the injury under investigation. It was common ground that this involved a typographical error which should be corrected. 39 Had the matter rested there, the mistake in relation to the back injury might have been corrected by the Registrar of the Commission, who has power to issue a replacement medical assessment certificate to correct "an obvious error": s 325(3). However, other errors were alleged in relation to the assessment and, on 25 July 2003, a notice of appeal was lodged, seeking a review by an Appeal Panel. The notice was in a printed form with details filled in where appropriate, and, otherwise, relevant boxes being ticked. Thus, in the section requiring a statement of grounds relied on for the appeal, four items specified in s 327(3) of the Workplace Injury Act are listed, and Mrs Vegan's solicitor had placed ticks against three boxes, being paragraphs (b), (c) and (d) of the statutory provision, which is set out below. The printed form was accompanied by an annexure dated 24 July 2003, which appears to have been filed at the same time as the appeal. It is headed "grounds of appeal" and contains in more discursive terms, the substance of the matters complained of. 40 The first ground, headed "Availability of additional information" made reference to further reports of Dr Manohar, a treating specialist, who referred specifically to complaints of pain and tenderness "on the left hand side of the body and left arm". As will be noted, Dr Adler had made no allowance for impairment of the left shoulder and arm and recorded that no complaint had been made to Dr Manohar in relation to the left hand side of the body. 41 The second heading referred to the use of "Incorrect criteria". Under this heading were listed nine separate complaints, seven of which concerned alleged mistakes in the history recorded by Dr Adler. The eighth complained about a finding that Mrs Vegan had demonstrated "a full range of neck movement upon examination", which was said to be incorrect and inconsistent with medical reports of Drs Berry and Manohar, available to Dr Adler. The ninth complaint concerned a bone scan, which was said by Dr Adler to be undated, but which in fact bore a date of 17 October 2001. 42 Under the third heading "Demonstrable error" complaint was made of the transcription error in relation to the impairment of the back, noted at [38] above. 43 On 18 August 2003, the Registrar of the Commission gave directions for service by Mrs Vegan of a sealed copy of the notice of appeal and for the service of a statement as to whether the matter should be determined on the papers or not, to which the Council was directed to file and serve a reply. 44 The statement made on behalf of Mrs Vegan, in response to the direction, suggested that a further medical examination was required, "particularly in light of recent pathology which indicates that there are bilateral deficiencies". With it was enclosed a bone scan from Cabramatta Nuclear Medicine dated 4 August 2003, and thus post-dating the certificate of Dr Adler. 45 In its statement in response, the Council conceded that the error with respect to the back should be corrected. Otherwise, the Council dealt with the appeal on two primary bases. The first was to resist reliance on further medical reports, on the basis that Mrs Vegan had seen Dr Manohar on numerous occasions on and after 5 October 2001 and had ample opportunity to obtain a comprehensive medical opinion from him for the purpose of submission to Dr Adler. Although the expansive "grounds of appeal" referred to further reports by Dr Manohar, which the Council complained were not contained with the material served, there was no specific reference in the response to the scan provided by Cabramatta Nuclear Medicine dated 4 August 2003, which was referred to in the Appellant's statement as being enclosed with the statement. Secondly, in relation to the factual mistakes in the history taking, the Council noted that there had been no attempt to identify in what way these complaints established the use by Dr Adler of "incorrect criteria". 46 The Appeal Panel was constituted by two approved medical specialists and an arbitrator. On 11 December 2003 the Panel revoked the certificate given by Dr Adler and issued a new certificate in its place, containing the following assessments of permanent impairment: Body Part Total % of permanent loss … Neck … 10% Back … 5% Right arm at or above the elbow … 10% Left arm at or above the elbow … 8% 47 On 15 December 2003 solicitors for the Council wrote to the Registrar complaining that the reasons for the decision of the Appeal Panel were "brief and minimal". They sought clarification in respect of a number of issues and also requested an opportunity to be heard in relation to the issues raised in the letter. On 24 December 2003, the Registrar replied in the following terms: "I advise that the determination of the medical appeal panel is final and there is no provision for the Commission or panel to review or address the issues raised in your letter." Jurisdiction of the Court 48 The relief sought by the Council in the Common Law Division involved claims for: (1) a declaration that the decision of the Appeal Panel "involved jurisdictional error and was beyond power"; (2) an order that the decision of the Appeal Panel be quashed, and (3) an order that the Appeal Panel carry out its functions according to law. It would seem that the declaration was intended to provide the basis for the operative orders based on s 69 of the Supreme Court Act 1970 (NSW). There appears to have been no affidavit or statement in support of the relief, otherwise setting out the grounds on which the orders were sought. 49 Although the summons appeared to rely on jurisdictional error, the trial judge approached the matter on the basis that it would be sufficient if the Council established error of law on the face of the record: Campbelltown City Council v Vegan [2004] NSWSC 1129 at [37]. That language seeks to invoke s 69(3) of the Supreme Court Act which declares that the jurisdiction of the Court extends to an order "to quash the ultimate determination of a court or tribunal in any proceedings if that determination has been made on the basis of an error of law that appears on the face of the record of the proceedings". It was assumed in the course of argument that the relevant "tribunal" for this purpose was the Appeal Panel and that its certificate was its "ultimate determination" and constituted "the record" of "proceedings". 50 For present purposes, it is not necessary to consider whether different criteria might apply in accordance with general law principles and whether, if that were the case, they survive the statutory formulation of the jurisdiction. In Australian Securities and Investments Commission v Farley (2001) 51 NSWLR 494, at [9] Sperling J stated, in relation to s 69(3): "The phrase 'error of law' is not limited to jurisdictional error. Accordingly, since 1996 but subject to other legislation, this Court has had power to grant relief in the nature of certiorari for any error of law that appears on the face of the record of the proceedings (which includes the reasons for determination of the court or tribunal concerned). That includes non-jurisdictional error: see Hargrave v Slater (2000) 113 A Crim R 371 at 374 [15], per Davies A-J for what may be a contrary view." This passage, quoted with approval by this Court in Hanna v Department of Immigration, Multicultural and Indigenous Affairs [2004] NSWCA 275 at [28] should not be read too broadly. Thus, it would be wrong to infer that, prior to the introduction of s 69(3) in 1996, the Supreme Court had no power to quash a decision on the ground of error of law on the face of the record. Rather, the effect of sub-ss 69(3) and (4), taken together, was to expand the concept of the record, in circumstances where the provisions applied, beyond that identified in Craig v South Australia (1995) 184 CLR 163 at 181. 51 Nor does the judgment of Davies AJ in Hargrave v Slater (2003) 113 A Crim R 371 suggest anything to the contrary. At [15], his Honour was discussing s 65 of the Supreme Court Act, not s 69(3); further, he was seeking to draw a distinction between judicial and administrative proceedings. Two paragraphs later, at [17] his Honour quoted a passage from Craig which reflected the long-established view that certiorari was available against the acts of an inferior court or other tribunal, where error of law on the face of the record, not being jurisdictional error, was established: 184 CLR 175-176. 52 Section 69(5) of the Supreme Court Act provides: (5) Subsections (3) and (4) do not affect the operation of any legislative provision to the extent to which the provision is, according to common law principles and disregarding those subsections, effective to prevent the Court from exercising its powers to quash or otherwise review a decision. The effect of this provision is to maintain the operation of privative clauses in other legislation. That effect is not surprising, nor is it restricted to sub-ss (3) and (4). A section dealing with jurisdiction to grant relief should be understood as operating only in circumstances where such relief is available. The effect of a privative clause has sometimes been described as removing the basis of relief, by expanding the power of the inferior court or tribunal to make a valid and unreviewable decision despite apparent error: Deputy Commissioner of Taxation v Richard Walter Pty Ltd (1995) 183 CLR 168 at 194 (Brennan J); Darling Casino Ltd v NSW Casino Control Authority (1997) 191 CLR 602 at 630-631 (Gaudron and Gummow JJ); Plaintiff S157/2002 v Commonwealth (2003) 211 CLR 476 at [19] (Gleeson CJ), but cf at [64] (Gaudron, McHugh, Gummow, Kirby and Hayne JJ) . 53 This principle was potentially relevant in the present case because s 350 of the Workplace Injury Act provided protection from review in relation to "a decision of the Commission" under that Act or the Workers Compensation Act. That gave rise to a question as to whether the Appeal Panel was the Commission for the purposes of that section. However, no party contended that the Appeal Panel constituted the Commission and therefore no party contended that s 350 affected the jurisdiction of the Court. Thus, the parties accepted the reasoning of the primary judge at [31]-[36] rejecting reliance on s 350, which had been argued below. Parties to proceedings in the Court 54 The proceedings in the Common Law Division were commenced by way of a summons issued by the Council (the employer), joining as defendants, the employee (and claimant in the Commission) and the Registrar, Workers Compensation Commission. The WorkCover Authority of New South Wales, constituted pursuant to s 14 of the Workplace Injury Act, being a statutory body representing the Crown, was joined as a third defendant in the proceedings below, apparently in place of the Registrar. In this Court, the Council proceeded against Mrs Vegan, the members of the Appeal Panel who made the decision and the WorkCover Authority. 55 In proceedings to review the decision of an inferior tribunal, absent some statutory provision to the contrary, it will usually be necessary to join the tribunal: see SAAP v Minister for Immigration and Multicultural and Indigenous Affairs (2005) 79 ALJR 1009 at [43], [91], [153], [180]. The appropriateness of that course, particularly where an order is sought requiring further steps to be taken by the inferior tribunal, is self-evident: unless joined, the tribunal will not be bound by the order. On the other hand, it is not necessarily appropriate to name the members of the tribunal: see Re Ruddock; Ex parte Reyes (2000) 75 ALJR 465 at [25] (McHugh J). It will usually be preferable to identify the tribunal by its official designation, so that persons who may constitute the tribunal if it is reconstituted will be bound. However, where the tribunal is an ad hoc body, appointed by an official as occasion arises, a different course may be appropriate. Whether the particular Panel still exists is not known. It would not be appropriate to order them to take particular steps: c.f., in a case of prohibition, Clifford and Sullivan [1921] 2 AC 570 at 584. The Registrar was not joined in this Court, but should have been because, if the appeal is allowed, an order should be made directing the Registrar to take appropriate steps. 56 There was discussion at the hearing of the appeal, however, as to the propriety of the Authority being a party to the proceedings and the potential costs consequences of that step. 57 The WorkCover Authority is given a general responsibility for the administration of the workers compensation legislation (Workplace Injury Act, ss 22 and 23) and, pursuant to s 106, a right to be heard in proceedings before the Commission. It was not submitted, however, that there was a statutory right of intervention or appearance in proceedings in other jurisdictions. 58 There are at least two situations where it is not uncommon for bodies with responsibilities for the administration of particular legislative schemes to seek to appear in court proceedings involving the operation of those schemes. First, it may well be appropriate for such a body to assist a court in relation to matters of powers and procedures, in the manner accepted in The Queen v Australian Broadcasting Tribunal; Ex parte Hardiman (1980) 144 CLR 13 at 35-36. That function may more readily be undertaken by a body like the WorkCover Authority, which, not being the decision-maker, will not be compromised in the future exercise of its powers. 59 The second function is one which can arise where the legislative scheme is established to avoid the costs of adversarial litigation where one side may not be adequately represented. It is doubtful whether a decision-maker should take on that role, but an independent administrator may be able to do so: cf Oshlack v Richmond River Council (1998) 193 CLR 72 at [46] (Gaudron and Gummow JJ), in relation to the inappropriateness of local government authorities becoming protagonists in litigation involving their exercise of statutory powers. 60 In some circumstances there may be no true opponent other than the decision-maker, as in cases where there is a government scheme for the provision of a benefit and the parties in the proceedings are the applicant and the authority which has refused the application. In such cases an independent body with responsibility for administering the scheme may be an appropriate person to support the decision under challenge. 61 In the present case, there were two active parties to the litigation, namely the worker and her employer. In those circumstances, as counsel for the Authority recognised, there was a limited role for the Authority to play. There can be no suggestion that the Authority exceeded its proper role, but there is an issue as to the propriety of joining it as a party, either below, or in the appeal. The Authority sought no relief in the proceedings, nor was any relief sought against it. It had no legal interest in the outcome of the dispute between the worker and the employer. It was not necessary to join it as a party under Part 8, r 2 of the Supreme Court Rules 1970 (NSW) (as then in force) in order for the proceedings to be properly constituted. Nor was it so joined. It appears to have been added under Part 8, r 8: but it was not a person who "ought" to have been joined, nor was it a person whose joining was "necessary" to ensure that the matters in dispute were effectually and completely determined. 62 There is no relevant statutory provision in the present case equivalent to that relied upon by the Australian Securities Commission in Australian Securities Commission v Ampolex Ltd (1995) 38 NSWLR 504 at 509 (Kirby P). Nor was this a case where a person, not a party to the proceedings below, but the recipient of a subpoena, sought to challenge the decision of a trial judge refusing an application for anonymity: see Witness v Marsden (2000) 49 NSWLR 429. In such a case the appellant was subject to a court order and had a direct interest in the matter sought to be challenged. 63 Nevertheless, an order for its joinder having been made below, counsel for the Authority submitted that it was a proper party to the appeal. That, however, does not follow. Part 51, r 9 provides: 9(1) Each party to the proceedings in the court below who is affected by the relief sought by a notice of appeal or is interested in maintaining the decision under appeal shall be joined as a party appellant or respondent to the appeal. If the Authority had no legal interest in the proceedings below, it follows that there was no obligation to join it to the appeal, nor was it appropriate to do so. This Court has power to remove a person who has been joined as a party and should, in appropriate circumstances do so. Normally it would only exercise that power on application by a party and no application was made in the present circumstances. 64 In substance, the Authority's role was confined to that of an amicus curiae. That was entirely appropriate. It follows, however, that in the ordinary event it should neither receive a favourable order for its costs, nor should it pay the costs of the successful party merely because it made submissions in support of the unsuccessful party. There will be no order as to its costs in the present case. Statutory scheme in relation to "claims" 65 Chapter 7 of the Workplace Injury Act is entitled "New claims procedures". Relevantly for present purposes, Part 7 of Chapter 7 makes provision for the resolution of a "medical dispute", a term defined in s 319 as follows: medical dispute means a dispute between a claimant and the person on whom a claim is made about any of the following matters or a question about any of the following matters in connection with a claim: (a) the worker's condition (including the worker's prognosis, the aetiology of the condition, and the treatment proposed or provided), (b) the worker's fitness for employment, (c) the degree of permanent impairment of the worker as a result of an injury, (d) whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality, and the extent of that proportion, (e) the nature and extent of loss of hearing suffered by a worker, (f) whether impairment is permanent, (g) whether the degree of permanent impairment of the injured worker is fully ascertainable. 66 Part 7 provides for the appointment of "approved medical specialists", to whom a medical dispute may be referred for assessment: s 321. The conduct of an assessment is provided for in ss 322 and 323. The determination is effected by giving a "medical assessment certificate", pursuant to s 325. 67 In addition, s 326 of the Workplace Injury Act provides: 326 Status of medical assessments (1) An assessment certified in a medical assessment certificate pursuant to a medical assessment under this Part is conclusively presumed to be correct as to the following matters in any proceedings before a court or the Commission with which the certificate is concerned: (a) the degree of permanent impairment of the worker as a result of an injury, (b) whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality, (c) the nature and extent of loss of hearing suffered by a worker, (d) whether impairment is permanent, (e) whether the degree of permanent impairment is fully ascertainable. (2) As to any other matter, the assessment certified is evidence (but not conclusive evidence) in any such proceedings. 68 It may be noted that the matters which are conclusively presumed to be correct in the certificate are the matters identified as the subject of a medical dispute, in s 319, other than pars (a) and (b) of the definition. 69 A party to a medical dispute may appeal against a medical assessment which respect to the matters covered by s 326(1) and on limited grounds: see s 327. The constitution of an Appeal Panel and the nature of the appeal is dealt with in s 328, in terms which will be considered further below. There is, however, provision for further medical assessment, in s 329, which provides as follows: 329 Referral of matter for further medical assessment (1) A matter referred for assessment under this Part may be referred again on one or more further occasions for assessment in accordance with this Part, but only by: (a) the Registrar as an alternative to an appeal against the assessment as provided by section 327, or (b) a court or the Commission. (2) A certificate as to a matter referred again for further assessment prevails over any previous certificate as to the matter to the extent of any inconsistency. 70 The operative parts of Chapter 7, presently relevant, commenced on 1 January 2002. As will be recalled, the injury to Mrs Vegan occurred on 29 August 2001 and she appears to have been in receipt of workers compensation payments prior to 1 January 2002. However, her claim for a payment for permanent impairment, pursuant to ss 66 and 67 of the Workers Compensation Act, was not made until 20 August 2002. 71 The legislative scheme distinguishes between an "existing claim" and a "new claim": s 250. The definition of "new claim" is any claim that is not an existing claim. The term "existing claim" is defined as follows: existing claim means a claim for compensation that is made before the commencement of this section or a related claim that is made or entitled to be made (whether before or after the commencement of this section). … related claims are claims or further claims for compensation in respect of the same injury, whether or not the claims are in respect of the same kind of compensation. 72 The term "compensation" is defined to include "any monetary benefit" under the Workers Compensation Acts, that is under the Workers Compensation Act 1987 or the Workplace Injury Act: see Workplace Injury Act, s 4(1). Because Mrs Vegan had a claim for compensation in late 2001, and because the claim in relation to permanent impairment was a further claim for compensation in respect of the same injury, the latter claim would appear to be a "related claim" and hence an "existing claim", for the purposes of s 250. The transitional provisions are contained in Part 18C of Schedule 6 of the Workers Compensation Act. Clause 2 of that Part provides that the Workers Compensation Acts "apply to and in respect of an existing claim" as if the 2001 Amendment Acts had not been enacted. However, that clause is subject to other provisions in the Part (sub-cl 2(2)) and cl 5 provides that regulations may be made requiring existing claims to be treated as new claims for the purpose of the Workers Compensation Acts or specified provisions thereof. Those claims are identified as "transferred claims" and "cease to be existing claims". 73 The relevant savings and transitional provisions are to be found in Part 23 of the Workers Compensation Regulation 2003 (NSW). Clause 224, in Part 23, is headed "Transfer of existing claims" and provides as follows: 224(1) On and from 1 April 2002, each existing claim in respect of which there is no pending application for determination by the Compensation Court is to be treated as a new claim for the purposes of the Workers Compensation Acts (under clause 5 of Part 18C of Schedule 6 to 1987 Act). Specific provision is made in the preceding clause in relation to the "assessment of impairment dispute", in the following terms: 223 The following modifications are prescribed to Part 7 of Chapter 7 of the 1998 Act as that Part applies to a new claim in respect of an injury received before the day on which that part commences: (a) omit section 322 (Assessment of impairment), (b) omit section 323 (Deduction for previous injury or pre-existing condition or abnormality). 74 The Authority contended that clause 223 applied in relation to Mrs Vegan's claim, a conclusion which was not disputed by the parties. Although s 323 of the Workplace Injury Act has no relevance, s 322 provides that the assessment of the degree of permanent impairment is to be made in accordance with the WorkCover Guidelines: s 322(1). Correctly, the Panel appears to have made its assessment in accordance with the "Table of Disabilities", which operated under the earlier legislation and which was applied by Dr Adler. 75 The Panel's reasons state that the WorkCover Guidelines may provide for the procedure on appeal. That provision is not excluded by the transitional provisions. In fact the guidelines so provide at Chapter E which forms part of what are described as "WorkCover Medical Assessment Guidelines". The reference by the Appeal Panel in paragraph 11 of its reasons is to those guidelines which, it notes, "set out the practice and procedure in relation to disputes in the Commission". Nature of the appeal 76 An appeal from an assessment by an approved medical specialist is provided in s 327 of the Workplace Injury Act which reads as follows: 327 Appeal against medical assessment (1) A party to a medical dispute may appeal against a medical assessment under this Part, but only in respect of a matter that is appealable under this section and only on the grounds for appeal under this section. (2) A matter is appealable under this section if it is a matter as to which the assessment of an approved medical specialist certified in a medical assessment certificate under this Part is conclusively presumed to be correct in proceedings before a court or the Commission. (3) The grounds for appeal under this section are any of the following grounds: (a) deterioration of the worker's condition that results in an increase in the degree of permanent impairment, (b) availability of additional relevant information (being evidence that was not available to the appellant before the medical assessment appealed against or that could not reasonably have been obtained by the appellant before that medical assessment), (c) the assessment was made on the basis of incorrect criteria, (d) the medical assessment certificate contains a demonstrable error. (4) An appeal is to be made by application to the Registrar. The appeal is not to proceed unless it appears to the Registrar that at least one of the grounds for appeal specified in subsection (3) exists. (5) If the appeal is on a ground referred to in subsection (3) (c) or (d), the appeal must be made within 28 days after the medical assessment appealed against, unless the Registrar is satisfied that special circumstances justify an increase in the period for an appeal. (6) If the appeal is on a ground referred to in subsection (3) (a) or (b), the Registrar may refer the medical assessment for further assessment under section 329 as an alternative to an appeal against the assessment. (7) There is to be no appeal against a medical assessment once the dispute concerned has been the subject of determination by a court or the Commission or agreement registered under section 66A of the 1987 Act. 77 As can be seen from sub-ss 327(1) and (2), the subject matter of an appeal is limited to a matter identified in a medical assessment certificate which is "conclusively presumed to be correct". Those matters are identified in s 326, set out above at [67]. Quite apart from the transitional regulations, cl 4 of Part 18C of Schedule 6 to the Workers Compensation Act potentially has an effect different from s 327(1) and (2). Clause 4 provides as follows: 4 Disputes concerning lump sum compensation claims (1) In the case of a new claim in respect of an injury received before the commencement of the lump sum compensation amendments, compensation under Division 4 of Part 3 (as in force before the commencement of those amendments) may not be awarded by the Commission if there is an impairment dispute unless the dispute has been assessed by an approved medical specialist under Part 7 of Chapter 7 of the 1998 Act. (2) An assessment certified in a medical assessment certificate pursuant to the medical assessment of an impairment dispute is conclusively presumed to be correct as to the matters in dispute in any proceedings in respect of the claim for compensation concerned. (3) For the purposes of this clause, Part 7 of Chapter 7 of the 1998 Act extends (with such modifications as may be prescribed by the regulations) to the assessment of an impairment dispute as if it were a medical dispute under that Part. (4) In this clause, impairment dispute means a dispute about whether a loss or impairment exists and, if so, the nature and extent of the loss or impairment. 78 As may be seen, that which is conclusively presumed to be correct under sub-cl 4(2) is significantly broader than the matters identified in s 326. Accordingly, if sub-cl 4(2) applies, the matters which can be the subject of an appeal would appear to be expanded for the purposes of s 327. On the other hand, if cl 4 is read as a coherent whole, it would seem only to apply to a "new claim", as identified in sub-cl (1). Clause 1 of Part 18C defines "new claim" as having the same meaning as in Chapter 7 of the Workplace Injury Act. For the reasons set out at [72] above the better view is that Mrs Vegan had an existing claim, and hence not a new claim, and hence cl 4 had no operation in this case. As no party sought to argue against this conclusion, it should be accepted and the scope of the appeal to the Appeal Panel should be determined in accordance with s 327. 79 The constitution of the Panel, the procedures before the Panel and its powers in dealing with an appeal are all set out in s 328, which reads as follows: 328 Procedure on appeal (1) An appeal against a medical assessment is to be heard by an Appeal Panel constituted by 2 approved medical specialists and 1 Arbitrator, chosen by the Registrar. (2) The appeal is to be by way of review of the original medical assessment. The WorkCover Guidelines may provide for the procedure on an appeal. (3) Evidence that is fresh evidence or evidence in addition to or in substitution for the evidence received in relation to the medical assessment appealed against may not be given on an appeal unless the evidence was not available to the appellant before that medical assessment or could not reasonably have been obtained by the appellant before that medical assessment. (4) When attending an Appeal Panel for the purposes of an assessment, an injured worker is entitled to be accompanied by a person (whether or not a legal adviser or agent) to act as the injured worker's advocate and assist him or her to present his or her case to the Appeal Panel. (5) The Appeal Panel may confirm the certificate of assessment given in connection with the medical assessment appealed against, or may revoke that certificate and issue a new certificate as to the matters concerned. Section 326 applies to any such new certificate. (6) The decision of a majority of the members of an Appeal Panel is the decision of the Appeal Panel. 80 As noted above, s 326 provides that certain "matters" will be conclusively presumed to be correct, as certified by the approved medical specialist. It is only those "matters" which can be the subject of an appeal under s 327. Further, the grounds of appeal are limited to those specified in s 327(3). 81 Where it is said that there has been a deterioration in the worker's condition, or additional relevant information is available, the Registrar has a power (though no obligation) to refer the matter for further assessment by an approved medical specialist: s 327(6) and s 329. 82 It is apparent that the Registrar must be satisfied that one of the grounds for appeal exists, before an appeal is allowed to proceed: s 327(4). Although the Council seeks to set aside the decision of the Appeal Panel, it does not complain as to the Registrar's exercise of power under s 327(4). Accordingly, no consideration was given to the correctness of any decision made by the Registrar, although it was suggested some limit might be placed on the power of the Court to review the decision of the Panel on the basis that it should be assumed that at least one of the grounds for appeal existed, because determination of that precondition to an appeal is reposed in the Registrar. 83 The argument that the Appeal Panel exceeded its powers required a consideration of the nature of the appeal. Relevant limitations were said to be expressed by, or implied from, the following points, based on statutory elements: (1) the limited grounds of appeal provided in s 327(3); (2) the fact that the appeal was described as being "by way of review of the original medical assessment" in s 328(2); (3) the restrictions on the use of evidence other than that not reasonably available to the appellant at the time of the medical assessment in s 328(3), and (4) the nature of the powers conferred on the Panel by s 328(5). 84 In relation to point (1), it is convenient to deal more fully with the grounds of appeal in considering below the application of the statutory provisions. However, it is clear that the grounds do not clearly reflect distinctions found in other areas of the law, such as a distinction between law and merits, or between errors of principle and the application of relevant principles, or between jurisdictional and other errors, although analogous categories could be formulated. One difficulty for the purposes of forming a clear picture of the nature of the appeal, based on the grounds, is the lack of clarity in ground (d), namely that the certificate contains "a demonstrable error". 85 The second point relied upon was the use of the term "review" in s 328(2). This, it was argued, precluded a hearing de novo. That was especially so when taken in combination with the limitation on additional evidence contained in s 328(3), being point (3). This approach tended to demonstrate the difficulty with too close a dissection of the statutory language. For example, where there had been a deterioration of the worker's condition (expressly identified as a ground of appeal), it would be likely that fresh evidence would be available and admissible so that the assessment might well be by way of a hearing de novo. Indeed, the power of the Registrar to refer such a case for a fresh assessment, as an alternative to an appeal, tends to confirm that conclusion. 86 Similarly, the scope of the powers of the Appeal Panel noted in point (4), to "confirm" the existing certificate, or to revoke it and issue a new certificate, provides little assistance as to the nature of the appeal. 87 The relevance of this analysis from the point of view of the current proceedings was to determine whether the Appeal Panel was entitled to carry out its functions, whether or not satisfied as to the existence of a valid ground of appeal; and whether, if there were a valid ground or grounds of appeal, its functions were limited to correcting so much of the certificate as might be affected by the established error or errors. These are matters which will need to be considered below in addressing the arguments presented by the parties. Grounds relied on before Panel: additional material 88 As noted above, the grounds of appeal did not rely upon deterioration in the condition of Mrs Vegan, but did rely upon the other three matters specified in s 327(3). 89 The first ground alleged the availability of additional information. This ground sought to identify medical reports of Dr Manohar, copies of which were said not to be available at the time of referral to the approved medical specialist. The application to resolve a medical dispute was received by the Commission on 10 December 2002. It appears to have been accompanied by reports of Dr Manohar dated 5 October 2001, 4 January 2002, and 22 March 2002 and a report of Dr Neil Berry, dated 25 July 2002. The additional material identified in the Appeal Panel's reasons were a report from Dr Manohar dated 2 September 2003 and a further report from Cabramatta Nuclear Medicine by Dr Kaushik, of 4 August 2003. The significance of the further report from Dr Manohar (which summarised his earlier reports, with some elaboration and which extended to 17 pages, together with a table of permanent impairment), was the express reference to 10% impairment in both the left and right arms, at and above the elbow. The grounds of appeal stated: "These reports particularly relate to complaints of pain and tenderness on the left hand side of the body and left arm. This is particularly relevant in light of the Approved Medical Specialist's comments in paragraph 9, points 3 and 4 on page 10." These passages in Dr Adler's certificate and reasons refer to his express finding that there was no impairment on the left side. 90 The report of Cabramatta Nuclear Medicine, dated 4 August 2003, also referred to bilateral clinical features. In describing Mrs Vegan's general history, Dr Adler had stated (report, p 3) that the day after the incident, Mrs Vegan: "… first noted right shoulder pain such that she had difficulty elevating her right arm at all. She agrees that it was only the right shoulder. She consulted a general practitioner who recommended she cease work, and then referred her to Dr Manohar, Rehabilitation Specialist, who assessed her on the 5th October 2001. He noted her description of right shoulder and neck pain." 91 In fact, Dr Manohar's report of 30 November 2001 had noted: "On examination today, there is some tension over the latissimus dorsi and over the left shoulder." On 4 January 2004 Dr Manohar reported that Mrs Vegan still had "cervico-thoracic junction ache extending to the shoulder tips". That language also appeared in a report of 22 March 2002. 92 The further report of Cabramatta Nuclear Medicine, dated 4 August 2003 concluded: "In view of the localised tenderness in the upper thoracic spinous processes and in the medial scapular margins bilaterally, the scan findings are consistent with clinical assessment of the bilateral trapezius and rhomboid enthesopathy." 93 The Appeal Panel concluded that Dr Manohar's new report did not satisfy the requirements of s 328(3) and hence could not be relied upon. As will appear below, the Appeal Panel did rely upon the new nuclear medicine report, but no significance was attached to that matter in the course of argument in this Court and it need not be addressed further. Other grounds relied on before Panel 94 The second complaint made in the statement of grounds of appeal to the Appeal Panel was that the approved medical specialist made factual errors in his statement of the general and clinical history set out in his certificate. Broadly speaking, these complaints fell into three categories, namely: (a) errors as to objective facts, such as Mrs Vegan's period of full-time work and work on light duties; (b) errors, according to Mrs Vegan, in the recording of her complaints, and (c) errors in the conclusions drawn from things she said or did not say. 95 These complaints were all said to demonstrate that the assessment was made on the basis of "incorrect criteria". It is arguable that factual errors made by an approved medical specialist, as recorded in the certificate, may be "demonstrable errors", but they would not usually satisfy the "incorrect criteria" ground. That must refer to such matters as the tests set out in the Guidelines, where they are applicable. The transcription error contained in the certificate was relied upon as a "demonstrable error". It was also an "obvious error" which was capable of correction by the Registrar and was conceded by the Council to be an error which required correction. 96 The Council did not submit that the determination of the Panel was reviewable because there was a labelling error in the grounds of appeal: in other words, the matters identified as incorrect criteria could be relied upon to establish demonstrable error and there was no relevant flaw in the decision of the Appeal Panel, arising from miscategorization. The principal question in relation to these grounds for relief therefore resolved itself into whether there were "demonstrable errors". 97 Whether the Panel erred in law in relation to this aspect of the case will depend upon a consideration of the reasons given by the Panel for its determinations. However, because there is a challenge to the adequacy of those reasons, it is convenient to defer consideration of these matters until the adequacy of the reasons has been addressed. The duty to give reasons 98 As a further and separate contention, the Council argued that the certificate given by the Appeal Panel was invalid because it was not accompanied by adequate reasons. This contention involved two elements. The first was whether there was a statutory obligation to give reasons. Such a requirement appears in s 325(2) in relation to a "medical assessment certificate". As appears from a reading of s 325 as a whole, the context in which that obligation is imposed is concerned with a certificate given by the approval medical specialist, to whom the medical dispute is referred. The section reads: 325 Medical assessment certificate (1) The approved medical specialist to whom a medical dispute is referred is to give a certificate (a medical assessment certificate ) as to the matters referred for assessment. (2) A medical assessment certificate is to be in a form approved by the Registrar and is to: (a) set out details of the matters referred for assessment, and (b) certify as to the approved medical specialist's assessment with respect to those matters, and (c) set out the approved medical specialist's reasons for that assessment, and (d) set out the facts on which that assessment is based. (3) If the Registrar is satisfied that a medical assessment certificate contains an obvious error, the Registrar may issue, or approve of the approved medical specialist issuing, a replacement medical assessment certificate to correct the error. (4) An approved medical specialist is competent to give evidence as to matters in a certificate given by the specialist under this section, but may not be compelled to give evidence. 99 There is no equivalent provision in relation to the Appeal Panel, the obligations of which are largely contained in s 328, set out at [79] above. At s 328(5), there is provision for the Appeal Panel to "confirm the certificate of assessment" or, in the alternative, there is power to revoke that certificate "and issue a new certificate as to the matters concerned". The provision then expressly provides that s 326 applies to any such new certificate: there is no express picking up of s 325(2). 100 Although the certificate given by an approved medical specialist is identified as a "medical assessment certificate" in s 325(1), that terminology is only used in s 325(2) and (3) and in s 326(1) and s327(2). However, it may be doubted that any different meaning is intended in s 328(5). Nevertheless, if the Appeal Panel confirms the certificate given by the approved medical specialist, it is a little awkward to treat s 325(2) as applying to that certificate, so that the reasons for the confirmation are to be set out in the certificate being confirmed. On the other hand, if the certificate is revoked and a new certificate issued, s 325(2), in its terms, could apply to that certificate. Nor does the express reference to s 326, as having application to a certificate given by the Appeal Panel, demonstrate a clear intention to exclude the operation of other provisions. For example, it is doubtful that it is intended to exclude the operation of s 329, which permits referral for further assessment by the Registrar or a court or the Commission. The resulting certificate is said to prevail over "any previous certificate", and there is no reason to suppose that does not include a certificate given by an Appeal Panel. 101 There are some internal indications that s 325 is intended to apply only in relation to the process before an approved medical specialist. Thus s 325(3), which permits the Registrar to correct a certificate which contains an obvious error, provides that the Registrar may issue "or approve of the approved medical specialist issuing, a replacement medical assessment certificate". On balance the better view is that there is no express statutory obligation to give reasons. 102 The second basis upon which the Council submitted that there was an obligation on the Appeal Panel to give reasons was an obligation arising from the general law. In response, it was suggested that any such conclusion would run contrary to the reasoning of the High Court in Public Service Board of New South Wales v Osmond (1986) 159 CLR 656. 103 Mr Osmond was an officer employed under the Public Service Act 1979 (NSW), who had unsuccessfully applied for promotion to a senior position. The question was whether, absent a statutory obligation, the Public Service Board, through the relevant department head, was required to give reasons for the decision to appoint another applicant over Mr Osmond. The High Court held that it was not so required, there being no general law obligation requiring reasons to be given for administrative decisions. Gibbs CJ, in the course of a judgment with which Brennan, Wilson and Dawson JJ agreed, referred to the statement of this Court in Pettitt v Dunkley [1971] 1 NSWLR 376 at 388, stating the obligation of a court to give reasons: 159 CLR at 666. However, his Honour continued at 667: "That does not mean that the requirement is an incident of a process which is not judicial but administrative; there is no justification for regarding rules which govern the exercise of judicial functions as necessarily applicable to administrative functions, which are different in kind." His Honour continued, referring to the rationale for the distinction in the following terms: "Moreover, the principle that judges and magistrates ought to give reasons in any case in which an appeal lies from the decision provides a quite inadequate basis for the suggested further principle that a body exercising discretionary administrative powers must give reasons to enable persons affected by the exercise of the power to bring proceedings for judicial review." 104 The differential treatment of the exercise of judicial, as opposed to administrative, power (like the constrained bases for judicial review of administrative action) reflects the separation of powers, even within the State constitutional system. If the efficacy of subsequent legal processes were the test of the need for reasons, the distinction between a right of appeal and a right of judicial review might not be decisive. Indeed, at least if the appeal is by way of rehearing, a different logic might apply. Thus in Osmond v Public Service Board of New South Wales [1984] 3 NSWLR 447, in this Court, Priestley JA, who accepted an obligation to provide reasons, distinguished the earlier decision of the Court in Taylor v Public Service Board [1975] 2 NSWLR 278; (1976) 137 CLR 208 on the basis that Mr Taylor had a right of appeal by rehearing, whereas Mr Osmond did not: at 485. His Honour stated: "It is the fact that this is the only (and limited) way of testing the administrative decision made against him that is one of the necessary factors in my coming to the conclusion that natural justice requires the furnishing of reasons to him. Where a right of appeal exists as in Taylor's case it may well be that natural justice, as the law has so far developed, does not require reasons to be given as the officer concerned is not debarred from a further hearing of his case in which the absence of reasons will be immaterial." 105 Nevertheless, the current position, often restated, is that the justification for an obligation to give reasons is derived from the right of appeal granted in relation to an exercise of judicial power: see Pettitt v Dunkley, supra at [22]. Reliance is sometimes also placed on the principle "that justice must not only be done but it must be seen to be done": Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247 at 278E (McHugh JA), and also Housing Commission of NSW v Tatmar Pastoral Co Pty Ltd [1983] 3 NSWLR 378 at 386C (Mahoney JA). Why a breach of this obligation constitutes an appellable error, rather than (in appropriate cases) permitting an order in the nature of mandamus has not been fully explored, but it may be analogous to a breach of procedural fairness in an administrative law context. In any event, this principle gives only limited assistance with respect to the distinction between judicial and administrative decision-making. There are well-known policy reasons in favour of reasoned administrative decisions: see, eg, Osmond v Public Service Board [1984] 3 NSWLR 447 at 463 (Kirby P); and see Re Minister for Immigration and Multicultural and Indigenous Affairs; Ex parte Palme (2003) 216 CLR 212 at [105] (Kirby J). 106 It is clear that the High Court in Osmond treated the general law principle as covering not merely administrative officers, but also administrative tribunals: 159 CLR, 662-663. Although the authorities upon which Gibbs CJ relied in Osmond may no longer be as definitive as they once were (see, eg, R v Secretary of State for the Home Department; Ex parte Doody [1994] 1 AC 531), Osmond remains the law in this country. The difficulties which arise when pursuing judicial review in the absence of reasons, articulated by Dixon J in Avon Downs Pty Ltd v Federal Commissioner of Taxation (1949) 78 CLR 353 at 360, cannot, by themselves, provide a justification for implying an obligation to give reasons. The classification of the functions of the tribunal as administrative or judicial therefore remains an important element in the exercise. 107 The Workers Compensation Commission was held not to be a "court of a State" for the purposes of the conferral of judicial power pursuant to s 39(2) of the Judiciary Act 1903 (Cth) in Orellana-Fuentes v Standard Knitting Mills Pty Ltd (2003) 57 NSWLR 282, [111]-[114] (Ipp JA, Spigelman CJ and Handley JA agreeing). 108 To similar effect, in Trust Company of Australia Ltd v Skiwing Pty Ltd [2006] NSWCA 185, this Court held that the Administrative Decisions Tribunal was not a "court of the State" for the purposes of a conferral of Commonwealth judicial power pursuant to s 86(2) of the Trade Practices Act 1974 (Cth). However, the Chief Justice noted that a different categorisation may be appropriate in different contexts. In Skiwing the context required attention to the scope of Commonwealth judicial power under Chapter III of the Constitution: Spigelman CJ at [17]. For the purposes of State law, a blurring of the edges and the possibility of different categorizations for different purposes may be accepted. Thus, a number of State tribunals have been held to be "courts" for the purposes of the Suitors' Fund Act 1951 (NSW): see, eg, Australian Postal Commission v Dao (No. 2) (1986) 6 NSWLR 497. Ultimately the question must be approached as one of statutory construction, always acknowledging that the principle of Osmond has not been abandoned or diminished. 109 There are two reasons for thinking that Osmond does not apply in the present circumstances. First, Osmond concerned administrative decision-making and not to the exercise of judicial power. As will be noted further below, the assessment of permanent impairment undertaken by the Appeal Panel involves the application of a statutory test, by which legal rights as between an employee and employer are determined. Accordingly, it is an exercise in the nature of a judicial function, whatever the precise name or status of the Appeal Panel itself: see e.g., in a constitutional context, the indicia of judicial power discussed in Brandy v Human Rights and Equal Opportunity Commission (1995) 183 CLR 245 at 256-259 (Mason CJ, Brennan and Toohey JJ) and 267-269 (Deane, Dawson, Gaudron and McHugh JJ); and see Luton v Lessels (2002) 210 CLR 333 at [21]-[24] (Gleeson CJ, McHugh J agreeing), [63]-[76] (Gaudron and Hayne JJ), [123]-[131] (Kirby J) and [189] (Callinan J); and in this Court, Trust Company of Australia Ltd v Skiwing Pty Ltd [2006] NSWCA 185 at [18]-[29] (Spigelman CJ, Hodgson and Bryson JJA agreeing). 110 Secondly, the principle in Osmond, being concerned with the general law, is always subject to statutory modification. The areas in which administrative decision-makers are required to give reasons for the exercise of statutory power are growing steadily, sometimes by way of specific legislation and sometimes by way of more general provision, such as pursuant to s 13 of the Administrative Decisions (Judicial Review) Act 1977 (Cth). In relation to Commonwealth legislation, there is an express provision in the Acts Interpretation Act 1901 (Cth) identifying the requirements of an obligation to give written reasons: see s 25D, inserted in 1984. 111 Between 1984 and 2004 disputes under the Workers Compensation Act could be resolved in the Compensation Court. The obligation of judges in that Court to give reasons was clearly identified as an attribute of the judicial process in which they were engaged: see, eg, Soulemezis v Dudley (Holdings) Pty Ltd (1987) 10 NSWLR 247 at 257D-F (Kirby P), 268-269 (Mahoney JA) and 278-279 (McHugh JA); and see Mifsud v Campbell (1991) 21 NSWLR 725 at 728, affirming the principle, but in relation to the District Court. 112 The Compensation Court was abolished on 1 January 2004: see Compensation Court Repeal Act 2002 (NSW), s 4. Proceedings instituted in the Compensation Court concerning a matter arising under the Workers Compensation Acts, were transferred to the Workers Compensation Commission. The new legislative regime gives rise to three questions: (a) Is the Commission under the same obligation to give reasons as had been established in relation to the Compensation Court? (b) Did that obligation extend to the assessment of medical disputes by an Appeal Panel? (c) If there is such a duty, does its content vary from that imposed on the Compensation Court? 113 None of these issues was squarely addressed in argument in this matter. The answers to these questions are by no means obvious and require attention to the legislative history which is complex, as indicated, without reference to the 2001 Amendment Acts, by Kirby J in Vetter v Lake Macquarie City Council (2001) 202 CLR 439 at [67]-[68]. For example, in Chapter 4, Part 2, Div 6 of the Workplace Injury Act, various provisions relating to proceedings before the Commission and the Compensation Court were dealt with concurrently suggesting that, although their respective jurisdictions differed, they exercised similar functions, prior to the abolition of the Compensation Court. In any event, s 294(2) of the Workplace Injury Act provides: "(2) A brief statement is to be attached to the certificate setting out the Commission's reasons for the determination." 114 If the dispute before the Commission concerned a degree of permanent impairment of an injured worker, that aspect must be referred for medical assessment under Part 7, with the result that a certificate issued by an approved medical specialist will be conclusive in relation to the prescribed matters. One effect of the obligation imposed on the medical specialist to give reasons for his or her assessment will be that the determination of the Commission will be accompanied by reasons dealing both with the medical dispute and the remainder of the issues in dispute before the Commission. The obligation of the Commission to give reasons is imposed, it should be noted, despite the privative clause protecting the decisions of the Commission from review: s 350 of the Workplace Injury Act permits an appeal limited to decisions of the presidential member "in point of law": s 353(1). Thus it may be seen that the obligation imposed on the Commission to give reasons is not for the broad purpose of facilitating an appeal. 115 Because the determination of a medical dispute becomes, in effect, part of the decision of the Commission, and indeed may be the principal part of the Commission's determination, it would be anomalous if the resolution of a medical dispute were to be the subject of reasons only when undertaken by an approved medical specialist, and not when undertaken by an Appeal Panel. In Soulemezis, McHugh JA stated at 278D-E: "… [I]t is no longer correct to say that a judge has no duty to give reasons unless there is a right of appeal against his decision. If it was, an ultimate court of appeal would have no duty to give reasons. In my opinion, the duty rests on a wider basis: its foundation is the principle that justice must not only be done but it must be seen to be done." 116 Further, there is provision for a matter to be referred for assessment more than once (s 329), including by a court or the Commission. The fair operation of these powers would be hampered if the Registrar, a court or the Commission were not assisted with available reasons for a certificate given by an Appeal Panel, particularly in circumstances where the Panel had differed from the approved medical specialist. 117 In the absence of challenge to the principles established in Soulemezis, it should be accepted that the Appeal Panel was subject to an implied statutory obligation to give reasons. That conclusion follows from the foregoing analysis of the statutory context and from an understanding of the nature of the functions imposed on the Appeal Panel. Those functions might not constitute an exercise of judicial power for the purposes of the federal Constitution, but they are functions properly characterised as judicial in nature, for the purposes of determining their incidents. 118 It is not necessary to rely upon the exception permitted by Gibbs CJ in Osmond (at p 670) that "in special circumstances natural justice may require reasons to be given". An implied statutory obligation is no doubt informed by requirements of procedural fairness, but more directly depends upon the judicial nature of the function and the specific statutory context, as recognised by Handley JA in Attorney-General (NSW) v Kennedy Miller Television Pty Ltd (1998) 43 NSWLR 729 at 739, a case dealing with the obligation of a costs assessor to give reasons. That is not, of course, to deny the significance of general principles of procedural fairness, as a basis underlying the obligation of a judicial officer to give reasons for decisions. 119 A similar approach has been adopted to the decisions of a referee – see Xuereb v Viola (1989) 18 NSWLR 453 at 469 (Cole J) – and in relation to the Strata Titles Board – see Anderson Stuart v Treleaven (2000) 49 NSWLR 88 at [182]-[185]. 120 A contrary decision relied on by the WorkCover Authority was the decision of the Queensland Court of Appeal in York v General Medical Assessment Tribunal (2003) 2 Qd R 104. That was a case which turned upon the principle of procedural fairness that a person likely to be affected by an adverse conclusion, which is not obviously open on the known material, should be given notice of the possibility that the tribunal will reach such a conclusion, so that he or she can seek to answer it: at [23] (Jerrard JA, McMurdo P and Davies JA agreeing). His Honour referred, in support of that principle, to Commissioner for ACT Revenue v Alphaone Pty Ltd (1994) 49 FCR 576 at 591-592. The principle is well-established in relation to administrative decisions: see Re Minister for Immigration and Multicultural Affairs; Ex parte Miah (2001) 206 CLR 57 at [142] (McHugh J) and at [99] (Gaudron J) and [194] (Kirby J) to similar effect; the judgment of McHugh J is further explained by his Honour in Muin v Refugee Review Tribunal (2002) 76 ALJR 966 at [128]-[135]. While in York, the Court of Appeal rejected an obligation to give reasons (at [31]), there was only perfunctory consideration of the statutory context and the nature of the function being exercised. That was because the point was conceded. The test applied was the "special or exceptional circumstances" identified in Osmond. The conclusion is thus of limited assistance for present purposes. Adequacy of reasons 121 Where it is necessary for the Panel to make findings of primary fact, in order to reach a particular conclusion as to the existence, nature and extent of any physical impairment, it may be expected that the findings of material facts will be set out in its reasons. Where facts are in dispute, it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. More importantly, where more than one conclusion is open, it will be necessary for the Panel to give some explanation of its preference for one conclusion over another. That aspect may have particular significance in circumstances where the medical members of a Panel have made their own assessment of the applicant's condition and have come to a different conclusion from that reached by other medical practitioners, as set out in reports provided to the Panel. 122 On the other hand, to fulfil a minimum legal standard, the reasons need not be extensive or provide detailed explanation of the criteria applied by medical specialists in reaching a professional judgment: see Soulemezis at 273-274 (Mahoney JA) and 281-282 (McHugh JA). At least, that will be so where the medical science is not controversial: if it is, a more expansive explanation may be required. 123 The major changes made by the Appeal Panel were to double the percentage impairment in relation to the neck and add an 8% impairment in relation to the left arm at or above the elbow. Less significant changes were made to the assessment of the back, which was increased from 2% to 5% (and the typographical error corrected) and an increase in relation to the right arm at or above the elbow, from 8% to 10%. 124 The first matter identified by the Panel, by reference to the respective submissions of the Appellant and the Respondent involved the availability of the further comprehensive report of Dr Manohar, dated 2 September 2003. Although there appears also to have been a challenge to the admission of the report from Cabramatta Nuclear Medicine, the submissions for the Respondent did not identify any particular reason why that report should not be before the Panel. The Panel rejected the report of Dr Manohar, but concluded that the nuclear medicine report was not available prior to the AMS assessment, and could therefore be relied upon. The Panel declined to require the applicant to undergo a further clinical examination. The remaining findings and reasons provided by the Panel were succinctly stated (so far as relevant) in the following terms: "30. The Panel found that the Report of Cabramatta Nuclear Medicine could be included in panel deliberations and was particularly helpful in consideration of this matter. 31. The Panel found that anomalies concerning the history of this matter were sufficient to establish that incorrect criteria had been demonstrated. 32. That the error in relation to the impairment of the back was conceded by the respondent and should be rectified. 33. Evidence from the available Reports and MAC persuaded the Medical Assessment Panel that changes to the assessment were appropriate." The decision was to revoke the original certificate and issue a new certificate. 125 Three criticisms were made of these reasons, each of which should be accepted. The first was that the possible inaccuracies in the history of the matter did not establish "incorrect criteria" in the sense intended in s 327(3)(c): see [95] above. Secondly, there was no indication as to which of the errors were made out or as to the history which the Panel accepted as correct. Thirdly, there was no indication as to how the corrected history, or the report from Cabramatta Nuclear Medicine, resulted in the changes contained in the certificate, from that revoked. 126 It may be inferred that, once the report of Dr Manohar was put aside, the findings with respect to impairment of the left arm must have been based upon the nuclear medicine report of 4 August 2003, the references in the earlier reports of Dr Manohar dated 30 November 2001 (referring to "some tension over the latissimus dorsi and over the left shoulder") and of 4 January 2002, referring to an ache "extending to the shoulder tips". Dr Adler had arguably been wrong in stating that Dr Manohar made no findings in relation to the left side in part 9 of his reasons, where he explained discrepancies between his findings and the earlier reports. The Panel may also have relied upon (although it made no reference to) the report of Dr Berry which expressly referred to "bilateral shoulder pain". 127 Even if the Panel's reference to the nuclear medicine report and the reference to the errors in the history, may be seen as a basis for finding impairment of the left arm, that is largely a matter of speculation and does not explain any particular level of impairment of that arm. Nor does it explain the increases in the percentage impairment in each of the other areas. No explanation is given for any of the departures from the findings of Dr Adler. 128 No doubt the assessment of physical impairment involves matters of evaluation and judgment by medical specialists. Such matters are often not reducible to precise explanations, and the choice of a particular figure will only be a point within a legitimate range. The content of reasons must be assessed with those factors in mind. Nevertheless, the present reasons demonstrate no attempt to explain significant departures from the assessment made by Dr Adler, nor any attempt to explain the errors which were said to exist in his reasons and findings, other than the bald statement of the preferred levels of impairment. 129 The Panel being under an obligation to supply reasons, it is clear that these were manifestly deficient and did not constitute compliance with the minimum requirements of that obligation. The next question is to identify the consequence which flows from this failing. Consequences of failure to provide reasons 130 There is extensive authority for the proposition that a failure, on the part of a tribunal exercising judicial functions, to give reasons for its decision will constitute an error of law which will permit the decision to be set aside on appeal, where the right of appeal is limited to errors of law: see, eg, Soulemezis (supra). Whether it also constitutes jurisdictional error is not a matter which needs to be determined, in relation to the statutory mandate of the Appeal Panel. It is sufficient for the purposes of relief under s 69 of the Supreme Court Act that an error of law has been identified, which appears on the face of the record. Because the record includes the reasons of the Panel, inadequacy of reasons will inevitably be such an error. As a result, the decision of the Panel may be set aside. Other errors 131 The other challenges to the decision of the Appeal Panel give rise to matters of some difficulty which do not require resolution. For example, a question was raised as to the power of the Appeal Panel to review the whole of the matter on the merits, once invested with jurisdiction. In other words, assuming that jurisdiction was attracted by a "demonstrable error" in one aspect of the decision of the medical specialist, which did not itself infect other parts of the certificate given by him, was the Appeal Panel limited to correcting the aspect of the certificate the subject of the error, or was it entitled (and required) to reconsider all aspects of the certificate? A related question was whether it was necessary for the Appeal Panel itself to identify relevant error, or whether it was sufficient that the Registrar had, pursuant to an unchallenged decision, found that it appeared to her that "at least one of the grounds for appeal specified in subsection (3) exists": s 327(4). 132 These questions are clearly not unrelated. Thus, if several grounds are identified in a notice of appeal, is it only those of which the Registrar is satisfied that the ground "exists" that can be dealt with by the Panel? Or if one is found to exist by the Registrar, can the Appeal Panel deal with all grounds which are in their view sustainable? If the Appeal Panel is limited to the ground or grounds found by the Registrar, must she specify the ground and can she specify more than one ground? 133 On first impression, it would seem that the Registrar is not required to determine the scope of the appeal because her role is merely to determine whether the appeal is to "proceed", the appeal itself being by way of review by the Appeal Panel. If only one ground for appeal exists, in the opinion of the Registrar, it would appear that the whole of the appeal may proceed and that, being satisfied as to one ground, the Registrar is not required to address other grounds. Similarly, to say that a ground of appeal "exists", as it "appears" to the Registrar, is to say no more than that the application before the Registrar satisfies the minimum requirements of s 327(3). There is no suggestion that the Registrar is required to consider whether the ground should succeed or to do more than satisfy herself that a ground, in conformity with s 327(3), is alleged and (perhaps) cannot be dismissed as patently untenable or colourable. 134 Whether this is entirely consistent with the approach accepted by the primary judge at [74]-[75] and apparently applied by Hislop J in Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission of NSW [2005] NSWSC 1260 at [24] is not entirely clear. In the present case, Wood CJ at CL adopted a particular view of the role of the Registrar not because (as in Riverina Wines) there had been a challenge to the decision of the Registrar, but because his Honour needed to determine whether the review undertaken by the Appeal Panel was "other than a review de novo": see at [77]. By that his Honour meant, adopting the categorisation in Allesch v Maunz (2000) 203 CLR 172 at [23], a completely fresh rehearing "in which the power of the appellate body to re-exercise the power must be exercised 'regardless of error'." His Honour concluded at [81]: "It would follow, in the present case, that once the Registrar as gatekeeper was satisfied, of the existence of the 2% error appearing on the face of the table, or of any other error, then it was appropriate for the matter to be referred to the Appeal Panel. It was then free to conduct a review upon the basis of the material properly available before it, without any need to make a formal finding itself as to the existence of an error falling within an available ground of appeal, and without being confined to the correction of that error." 135 The tendency of the legislature to identify the available grounds for an appeal, without separately determining the scope of the appellate tribunal, has given rise to difficulties in other situations. That is particularly so where the appellate tribunal has broad powers and many sources of jurisdiction. For example, in Vetter v Lake Macquarie City Council (2001) 202 CLR 439 at [38] the joint judgment of Gleeson CJ, Gummow and Callinan JJ (in which Hayne J relevantly agreed) noted that where an appeal to this Court was available where a party was aggrieved "in point of law or on a question as to the admission or rejection of evidence", this Court's powers might be limited to correction of the error, or might encompass the powers exercisable by the Compensation Court, as on a rehearing. The majority did not express an opinion on this question (at [38]) but Kirby J, who found it necessary to do so, concluded that the powers of this Court were limited to correcting errors of law. Thus his Honour stated [69]: "In the context of this legislative history, and despite the ungainly language, there can be little doubt that the purpose of Parliament was to limit both the jurisdiction and powers of the Court of Appeal to the determination of appeals on a point of law (or in relation to the admission or rejection of evidence). The alternative construction would be capricious, involving the need for jurisdiction to establish, relevantly, an error in point of law but thereafter allowing, and probably requiring, the Court of Appeal to exercise its powers to decide purely factual disputes." 136 A similar conclusion had been reached by this Court in North Broken Hill Ltd v Tumes (1999) 18 NSWCCR 412 at [22]-[24] (Beazley JA, Giles JA and Davies AJA agreeing), because the legislature had conferred exclusive jurisdiction on the Compensation Court to determine such matters. 137 Two factors suggest that such an approach would also be appropriate in relation to the powers of the Appeal Panel. First, if the Appeal Panel's powers were at large, the need to specify grounds of appeal limited to particular categories, would be rendered largely otiose. Secondly, the Appeal Panel is not a tribunal which has any powers other than those necessary to deal with the appeals in question. Thus, unlike this Court, it is not necessary to consider whether broad existing powers are exercisable in a particular case or not. On a tentative view, the approach adopted by the primary judge in the present case may have been in error and the powers of the Appeal Panel may be limited to addressing, and if thought necessary, correcting, errors identified in the certificate granted by the approved medical specialist, as specified by the appellant. However, it is not necessary to reach a final conclusion in relation to this aspect of the matter because the certificate must be set aside on other grounds and the matter remitted to the Appeal Panel for it to exercise its powers according to law. Costs 138 By its notice of appeal, the Appellant sought costs both in relation to the appeal and the proceedings below. Given the condition imposed on the grant of leave, an order for the costs of the appeal should not have been sought. 139 No condition was imposed on the grant of leave that there be no interference with the order for costs made below. That may have been because the judgment appealed from reserved the question of costs and it was not clear at that stage that any order had been made. The Court was not told the precise nature of the order for costs made below, nor was any submission made as to whether, if the Respondent was ordered to pay those costs, she would be entitled to a Suitors' Fund Certificate. Nor were submissions received as to what order as to costs would be appropriate in respect of the proceedings before the primary judge, if the appeal were allowed. Accordingly, the appropriate course is for this Court not to interfere with any costs order made below. Conclusions 140 I would propose the following orders: (1) Appeal allowed. (2) Subject to any objection being taken by the Registrar within 14 days, join the Registrar, Workers Compensation Commission, as a respondent to the appeal; (3) Set aside the order made in the Common Law Division dismissing the proceedings and in lieu thereof: (a) set aside the certificate issued by the Appeal Panel in matter number WCC 5067-2002, and (b) remit the matter to the Registrar for referral to an Appeal Panel constituted under s 328 of the Workplace Injury Act for determination according to law. (4) Pursuant to the condition imposed on the grant of leave to appeal, order the Appellant to pay Mrs Vegan's costs of the appeal. (5) Direct the Authority within 2 days to provide the Registrar with a copy of these orders and reasons for judgment. ********** 25/10/2006 - Amending initials of counsel - Paragraph(s) Coversheet 21/06/2007 - Spelling error in case cited - Paragraph(s) Headnote DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated.