New South Wales Supreme Court CITATION : Cameron v The Registrar of the Workers Compensation Commission of New South Wales [2008] NSWSC 704 HEARING DATE(S) : 19 February 2008 JUDGMENT DATE : 14 July 2008 JURISDICTION : Common Law JUDGMENT OF : Rothman J (i) The reconsideration of the matters arising under s 327(4) of the Workplace Injury Management and Workers Compensation Act 1998 by the delegate of the Registrar, Mr Wayne Wormald, issued on 5 February 2007 in matter number 6209-2005 between Plymold Seating Pty Ltd trading as Brookvale Tyres and Michael Cameron, be quashed. DECISION : (ii) The assessment of the Medical Appeal Panel dated 6 March 2007 in matter number 6209-2005, being an appeal by Plymold Seating Pty Ltd trading as Brookvale Tyres in relation to an application for assessment by Michael Cameron, be quashed. (iii) The application by the aforesaid Plymold Seating Pty Ltd trading as Brookvale Tyres, for reconsideration of the refusal of the Registrar to allow to proceed an appeal, by the aforesaid Plymold Seating Pty Ltd trading as Brookvale Tyres, against the medical assessment of 4 November 2005, be remitted to the Registrar to deal with in accordance with law. (iv) Liberty to apply in relation to costs and any consequential order. CATCHWORDS : ADMINISTRATIVE LAW – workers compensation – satisfaction of Registrar that ground of appeal exists or is made out – reconsideration of decisions under s 378 – assessment of whole person impairment – deductions for previous injury – role of Medical Appeal Panel - WORKERS COMPENSATION – appeal against medical assessment – role of Registrar in allowing appeal to proceed – reconsideration of decision – role of Medical Appeal Panel – not de novo hearing – requirement to find error. Supreme Court Act 1970 LEGISLATION CITED : Workers Compensation Act 1987 Workers Compensation Legislation Amendment (Miscellaneous Provisions) Act 2005 Workplace Injury Management and Workers Compensation Act 1998 CATEGORY : Principal judgment Australian National Industries Ltd v Spedley Securities Ltd (1992) 26 NSWLR 411 Builders Registration Board (QLD) v Rauber (1983) 57 ALJR 376 Campbelltown City Council v Vegan [2006] NSWCA 284; (2006) 67 NSWLR 372 Craig v South Australia [1995] HCA 58; (1995) 184 CLR 163 Crean v Burrangong Pet Food Pty Limited [2007] NSWSC 839 Ex parte Hebburn Ltd v Kearsley Shire Council (1947) 47 SR(NSW) 416; (1947) 64 WN(NSW) 107 Ex parte Northern Land Council [1981] HCA 74; (1981) 151 CLR 170 CASES CITED : Laws v Australian Broadcasting Tribunal [1990] HCA 31; (1990) 170 CLR 70 Maxwell v Murphy [1957] HCA 7; (1957) 96 CLR 261 Parisienne Basket Shoes Pty Ltd v Whyte [1938] HCA 7; (1938) 59 CLR 369 Public Service Association of South Australia v Federated Clerks' Union of Australia (SA) [1991] HCA 33; (1991) 173 CLR 132 Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission [2005] NSWSC 1260 Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission of NSW [2007] NSWCA 149 Smith v Liquip Services Pty Ltd [2007] NSWSC 687 Summerfield v Registrar of the Workers Compensation Commission [2006] NSWSC 515 Michael Cameron (Plaintiff) PARTIES : The Registrar of the Workers Compensation Commission of New South Wales (First Defendant) Plymold Seating Pty Ltd trading as Brookvale Tyres (Second Defendant) An Appeal Panel constituted pursuant to s 328 of the Workplace Injury Management and Workers Compensation Act 1998 (Third Defendant) FILE NUMBER(S) : SC 30071/2007 J Simpkins SC / L Morgan (Plaintiff) COUNSEL : Submitting appearance (First Defendant) D J Hooke (Second Defendant) Submitting appearance (Third Defendant) Leitch Hasson Dent Solicitors (Plaintiff) SOLICITORS : Crown Solicitor's Office (First Defendant) Edwards Michael Lawyers (Second Defendant) Crown Solicitor's Office (Third Defendant) LOWER COURT JURISDICTION : Workers Compensation Commission LOWER COURT FILE NUMBER(S) : 6209-2005 LOWER COURT JUDICIAL OFFICER : The Registrar and Medical Appeal Panel LOWER COURT DATE OF DECISION : 5 February 2007 and 6 March 2007 IN THE SUPREME COURT OF NEW SOUTH WALES COMMON LAW DIVISION ROTHMAN J 14 JULY 2008 30071/2007 Cameron v The Registrar of the Workers Compensation Commission of New South Wales & Ors JUDGMENT 1 HIS HONOUR: Mr Michael Cameron was injured at work on 14 April 2004. He had previously been injured. He now challenges in this Court the validity of a Medical Assessment Certificate issued by a Medical Appeal Panel ("the Appeal Certificate") under the Workplace Injury Management and Workers Compensation Act 1998. 2 One basis of the challenge is an error of law or jurisdiction in the decision of the delegate of the Registrar. The said delegate reconsidered an earlier decision to refuse to refer an appeal by Mr Cameron's employer, Plymold Seating Pty Limited trading as Brookvale Tyres ("Brookvale Tyres"). The appeal was against the Medical Assessment Certificate ("the Original Certificate" and/or "Original Assessment") issued by Dr Stuckey. The first and third defendants (the Registrar and the Medical Appeal Panel), as is appropriate, submit to any order of the Court save as to an order for costs. 3 Further, Mr Cameron challenges the Appeal Certificate and the reasons therefor as disclosing an error on the face of the record and/or being beyond jurisdiction, as a result of that allegedly invalid referral and on other grounds. It is necessary to deal with the background and procedural history before dealing with the legal issues to which the summons gives rise. Background and Procedural History 4 Mr Michael Cameron was, as a 19 year old, injured in a motorcycle accident resulting in fractures of the left leg. That accident occurred in 1982. In 1993 he underwent a laminectomy and spinal fusion for L5/S1 for symptomatic spondylolisthesis. The operation was successful with an extremely satisfactory outcome. Except for a short period (three months) during 1996 when Mr Cameron was off work due to back pain, he was able to work from 1994 through to 2004 without limitation. There were occasional "flare-ups" of back pain, for which Mr Cameron would seek and obtain medical attention, and he had regular x-rays to ensure that there was no worsening of the situation. 5 On 14 April 2004, while employed by Brookvale Tyres as a tyre fitter and/or mechanic, Mr Cameron was injured while dragging a compressor, which caught on the ground. He felt a pulling sensation in the left lower back and subsequent discomfort to the left buttock, hip region and back of thigh. Over a very short period symptoms worsened and Mr Cameron ceased work at the recommendation of his medical practitioner and was treated with anti-inflammatory medications and physiotherapy. 6 After almost two months, on 4 June 2004, he returned to full duties (having resumed after six weeks on light duties for reduced hours). On 9 June 2004, he resigned his work. He was unable to resume full-time work thereafter. He moved to the North Coast of New South Wales and commenced his own business as a boat mechanic working very limited hours because of his incapacity. 7 On 29 April 2005, application was made to the Workers Compensation Commission ("the Commission") to resolve a dispute, being the compensation for the workplace injury on 14 April 2004. The application was referred by an Arbitrator of the Commission to an Approved Medical Specialist ("AMS") for an assessment of whole person impairment ("WPI") under the Workplace Injury Management and Workers Compensation Act 1998 ("the Act"). 8 On 1 November 2005, an AMS (Dr Michael Stuckey) examined the plaintiff and, on 4 November 2005, issued the Original Certificate, which determined that Mr Cameron had a 24% WPI referable to his lumbar spine condition for the period on and after 14 April 2004. The assessment was based upon the categorisation of Mr Cameron's injury as falling within DRE Category IV. This had been adjusted to take account of interference with the daily activities of living and adjusted on account of the spinal fusion. The upward adjustment for the latter was 2%. Further, the Original Certificate assessed 8% WPI on account of the pre-existing injury (i.e. prior to 14 April 2004), including the surgery. The resultant 16% WPI ("the Original Assessment") was then, pursuant to the Act, to be the basis of the assessment of compensation. 9 On 8 December 2005, Brookvale Tyres appealed the Original Assessment on the basis of demonstrable error and incorrect criteria. There was no challenge to the categorisation of the injury as a DRE Category IV, but there was a submission that the categorisation of the pre-existing injury was inadequate in that the proper categorisation of Mr Cameron prior to the injury was also DRE Category IV. Issue was also taken with the adjustment of 2% on account of the surgery and the adjustment for the impact on activities of daily living because each, it was said, pre-dated the workplace injury. 10 On 27 January 2006, Ms Erin Stephens, delegate of the Registrar, determined that it did not appear to the Registrar that at least one of the grounds for appeal specified in subsection (3) existed: see Affidavit of Matthew Berenger p 148, s 327(4) of the Act, below. 11 On 23 March 2006, Brookvale Tyres applied to the Supreme Court, by Summons, challenging the decision of Ms Stephens. 12 On 1 November 2006, certain amendments to the Act became operative. Section 327 of the Act was amended and s 378 was inserted. Hereinafter, for convenience, and only where discrimination is necessary, the amended Act will be referred to as "the 2006 Act". As a consequence of the promulgation of the 2006 Act, Brookvale Tyres notified that it would discontinue the then Supreme Court proceedings and apply for reconsideration of the Registrar's decision of 27 January 2006. 13 These two steps were effected on 6 December 2006 and 11 December 2006 respectively. Brookvale Tyres and Mr Cameron filed submissions and, by decision dated 5 February 2007, Mr Wayne Wormald, another delegate of the Registrar, purported to reconsider the decision of Ms Stephens dated 27 January 2006, rescinded the decision and referred the appeal against the Original Assessment to a Medical Appeal Panel: Lee Affidavit, p 4 et seq. 14 The decision of 5 February 2007 purported to find that the "Employer's ground of appeal with respect to the Table 4.4 Modifiers is, on its face, valid and apparently credible, and cannot be dismissed as patently untenable or colourable". This was a reference to the judgments, or the reasons therefor, cited therein, being the reasons for judgment of Handley JA and Basten JA in Campbelltown City Council v Vegan [2006] NSWCA 284; (2006) 67 NSWLR 372. 15 The reference to the Table 4.4 Modifiers is a reference to the 2% adjustment on account of the surgery that predated the relevant workplace injury. Mr Wormald, as the delegate of the Registrar, determined that it was an error to include that adjustment because of the relevant date of the surgery. 16 It is conceded in these proceedings before the Court that it was both appropriate and legally correct to include the 2% adjustment on account of the pre-workplace injury surgery in the assessment of the WPI for the period after the workplace injury. However, it is submitted, before the Court in these proceedings, that the deduction to allow for the pre-existing injury would necessarily include the same 2% adjustment and was, otherwise, wholly inadequate and contrary to law and principle. As a matter of both principle and logic, if the effective WPI arising from any particular injury were required to be assessed by a calculation of current WPI and a deduction of WPI for the period immediately prior to the injury, then the surgery must be included in the post-injury WPI assessment. 17 On 5 March 2007, Mr Cameron's solicitor wrote to the Commission requesting a hearing for the purpose of making oral submissions to the Medical Appeal Panel. On 6 March 2007, the Medical Appeal Panel, Ms Eraine Grotte (Arbitrator), Dr William Lyons (AMS), and Dr Philippa Harvey-Sutton (AMS), determined the appeal. 18 The effect of the decision of the Appeal Panel was the issue of a Medical Assessment Certificate ("the Appeal Certificate" and/or "Appeal Assessment") of a WPI of 26% referable to the period after 14 April 2004 and a deduction of 20% WPI as a result of pre-existing injury, leaving an effective WPI of 6% resulting from the workplace injury. Legislation 19 The Parliament, as has already been noted, amended the Act in 2006 by, amongst other things, amending s 327 and inserting s 378. Otherwise, the legislative provisions remained, essentially and relevantly, unaltered. It is necessary to deal with the relevant legislative provisions in the Act (i.e. pre 1 November 2006) and the amended provisions in the 2006 Act. It is also necessary to examine some of the provisions of the Workers Compensation Act 1987. Those relevant provisions follow. The Act (pre 2006) 20 The long title of the Act is "an Act to provide for the effective management of work-related injuries and injury compensation for workers in respect of such injuries; and for other purposes". The other relevant sections are: " 3 System objectives The purpose of this Act is to establish a workplace injury management and workers compensation system with the following objectives: (a) to assist in securing the health, safety and welfare of workers and in particular preventing work-related injury, (b) to provide: • prompt treatment of injuries, and • effective and proactive management of injuries, and • necessary medical and vocational rehabilitation following injuries, in order to assist injured workers and to promote their return to work as soon as possible, (c) to provide injured workers and their dependants with income support during incapacity, payment for permanent impairment or death, and payment for reasonable treatment and other related expenses, (d) to be fair, affordable, and financially viable, (e) to ensure contributions by employers are commensurate with the risks faced, taking into account strategies and performance in injury prevention, injury management, and return to work, (f) to deliver the above objectives efficiently and effectively." " 4 Objectives (1) In this Act: 'incapacity' includes a disfigurement that is sufficient to affect the earning capacity of a worker or a worker's opportunities for employment. 'injury': (a) means a personal injury arising out of or in the course of employment, and (b) includes: (i) a disease contracted by a worker in the course of employment, where the employment was a contributing factor to the disease, or (ii) the aggravation, acceleration, exacerbation or deterioration of any disease, where the employment was a contributing factor to the aggravation, acceleration, exacerbation or deterioration …. 'permanent impairment compensation' means compensation for permanent impairment under section 66 of the 1987 Act. 'Registrar' means the Registrar of the Commission appointed under this Act. 'work injury' means an injury in respect of which compensation is payable." " 105 Jurisdiction of Commission and Compensation Court (1) Subject to this Act, the Commission has exclusive jurisdiction to examine, hear and determine all matters arising under this Act and the 1987 Act." " 322 Assessment of impairment (1) The assessment of the degree of permanent impairment of an injured worker for the purposes of the Workers Compensation Acts is to be made in accordance with WorkCover Guidelines (as in force at the time the assessment is made) issued for that purpose. (2) Impairments that result from the same injury are to be assessed together to assess the degree of permanent impairment of the injured worker. (3) Impairments that result from more than one injury arising out of the same incident are to be assessed together to assess the degree of permanent impairment of the injured worker. Note: Section 65A of the 1987 Act provides for impairment arising from psychological/psychiatric injuries to be assessed separately from impairment arising from physical injury. (4) An approved medical specialist may decline to make an assessment of the degree of permanent impairment of an injured worker until the approved medical specialist is satisfied that the impairment is permanent and that the degree of permanent impairment is fully ascertainable. Proceedings before a court or the Commission may be adjourned until the assessment is made." " 323 Deduction for previous injury or pre-existing condition or abnormality (1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality. (2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence. Note: So if the degree of permanent impairment is assessed as 30% and subsection (2) operates to require a 10% reduction in that impairment to be assumed, the degree of permanent impairment is reduced from 30% to 27% (a reduction of 10%). (3) The reference in subsection (2) to medical evidence is a reference to medical evidence accepted or preferred by the approved medical specialist in connection with the medical assessment of the matter. (4) The WorkCover Guidelines may make provision for or with respect to the determination of the deduction required by this section. Note: Section 68B of the 1987 Act makes provision for how this section applies for the purpose of calculating workers compensation lump sum benefits for permanent impairment and associated pain and suffering in cases to which section 15, 16, 17 or 22 of the 1987 Act applies. " " 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." " 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) The Registrar may refer a medical assessment for further assessment or reconsideration under section 329 as an alternative to an appeal against the assessment." " 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. … (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." " 331 Guidelines Medical assessments, appeals and further assessments under this Part are subject to relevant provisions of the WorkCover Guidelines relating to the procedures for the referral of matters for assessment or appeal, the procedure on appeals and the procedure for assessments." " 350 Decisions of Commission (1) Except as otherwise provided by this Act, a decision of the Commission under the Workers Compensation Acts is final and binding on the parties and is not subject to appeal or review. (2) A decision of or proceeding before the Commission is not: (a) to be vitiated because of any informality or want of form, or (b) liable to be challenged, appealed against, reviewed, quashed or called into question by any court. (3) The Commission may reconsider any matter that has been dealt with by the Commission and rescind, alter or amend any decision previously made or given by the Commission." " 366 Establishment of Commission (1) The Workers Compensation Commission of New South Wales is established by this Act. (2) The Commission has and may exercise such functions as are conferred or imposed on it by or under the Workers Compensation Acts or any other Act." " 368 Members of Commission (1) The Commission consists of the following members: (a) a President, (b) two Deputy Presidents, (c) a Registrar, (d) Arbitrators." " 371 Functions of Registrar (1) The Registrar has and may exercise all the functions of an Arbitrator. (2) The Registrar can delegate to any member or member of staff of the Commission any of the Registrar's functions under the Workers Compensation Acts, except this power of delegation. (3) The Registrar may exercise any of the functions of the Commission constituted by an Arbitrator to dismiss proceedings before the Commission." 2006 Act Amendments The relevant amendments to the Act are: " 327 Appeal against medical assessment … (4) An appeal is to be made by application to the Registrar. The appeal is not to proceed unless the Registrar is satisfied that, on the face of the application and any submissions made to the Registrar, at least one of the grounds for appeal specified in subsection (3) has been made out." " 378 Reconsideration of decisions (1) The Registrar, an approved medical specialist or an Appeal Panel may reconsider any matter that has been dealt with by the Registrar, the approved medical specialist or the Appeal Panel, respectively, and rescind, alter or amend any decision previously made or given. (2) Without limiting subsection (1), if the Registrar, an approved medical specialist or an Appeal Panel is satisfied there is an obvious error in the text of a decision, the Registrar, approved medical specialist or Appeal Panel may alter the text of the decision to correct the error. (3) The Registrar, an approved medical specialist or an Appeal Panel must reconsider any matter referred to it for reconsideration not later than 2 months after the referral is made. (4) An altered or amended decision is taken to be the decision of the Registrar, approved medical specialist or Appeal Panel. (5) Nothing in this section affects any other power under this Act or the 1987 Act to review or amend a decision. (6) In this section, 'decision' includes an assessment or further assessment by an approved medical specialist or an Appeal Panel." Workers Compensation Act 1987 The parts of the Workers Compensation Act that require reciting are: " 2A Relationship to Workplace Injury Management and Workers Compensation Act 1998 (1) The Workplace Injury Management and Workers Compensation Act 1998 is referred to in this Act as 'the 1998 Act'. (2) This Act is to be construed with, and as if it formed part of, the 1998 Act. Accordingly, a reference in this Act to this Act includes a reference to the 1998 Act. (3) In the event of an inconsistency between this Act and the 1998 Act, the 1998 Act prevails to the extent of the inconsistency. " 22 Compensation to be apportioned where more than one injury (1) If: (a) the death or incapacity of a worker, or (b) a permanent impairment suffered by a worker as referred to in Division 4 of Part 3, or (c) a liability under Division 3 of Part 3 to a worker, results from more than one injury to the worker, liability to pay compensation under this Act is to be apportioned in such manner as the Commission determines. (1A) Death, incapacity, loss or liability that results partly from one injury and partly from one or more other injuries is taken to have resulted from more than one injury. (2) Liability to pay compensation under this Act includes: (a) the liability of an employer (including an employer who is a self-insurer), and (b) the liability of an insurer under a policy of insurance in respect of the payment of that compensation (including a direct liability to the worker), and (c) a liability in respect of a claim under Division 6 of Part 4, and (d) in the case of a worker who is partially incapacitated for work, a liability that arises because the worker is entitled to be compensated under this Act as if totally incapacitated. (3) Liability to pay compensation under this Act is not to be apportioned by the Commission if the parties to whom the liability relates have agreed on the apportionment. (4) Liability to pay compensation under this Act may be apportioned by the Commission even though it is the liability of a single insurer in respect of different periods of insurance, but only if the employer or the Authority applies for such an apportionment. (5) The Commission may, on the application of any insurer or employer concerned or of the Authority, determine a dispute as to whether: (a) liability to pay compensation under this Act should be apportioned under this section, or (b) any such liability should be apportioned under this section in respect of different injuries. The determination of the Commission has effect despite any agreement on apportionment if the application for determination was made by an employer (in the employer's own right) or the Authority. … (7) A person who is liable to pay compensation under this Act is not entitled in any proceedings under this Act to a reduction in that liability by apportionment on account of the existence of any other person who is also liable to pay any part of that compensation unless that other person is a party to the proceedings. (8) This section applies to any liability arising before or after the commencement of this Act." " 48 Compensation payable despite existing incapacity (1) Compensation is payable under this Division in respect of an injury which, but for existing incapacity, would have resulted in total or partial incapacity for work of the worker. (2) Any such compensation is payable as if total or partial incapacity for work had in fact resulted from the injury. (3) In this section: 'existing incapacity' means total incapacity for work by disease or other cause: (a) not entitling the worker to compensation under this Act, and (b) existing at the time when the total or partial incapacity for work would otherwise have resulted from the injury." " 66 Entitlement to compensation for permanent impairment (1) A worker who receives an injury that results in permanent impairment is entitled to receive from the worker's employer compensation for that permanent impairment as provided by this section. Permanent impairment compensation is in addition to any other compensation under this Act. (2) The amount of permanent impairment compensation is to be calculated as follows: (a) if the degree of permanent impairment is not greater than 10%, the amount of permanent impairment compensation is to be calculated as follows: (b) if the degree of permanent impairment is greater than 10% but not greater than 20%, the amount of permanent impairment compensation is to be calculated as follows: (c) if the degree of permanent impairment is greater than 20% but not greater than 40%, the amount of permanent impairment compensation is to be calculated as follows: (d) if the degree of permanent impairment is greater than 40% but not greater than 75%, the amount of permanent impairment compensation is to be calculated as follows: (e) if the degree of permanent impairment is greater than 75%, the amount of permanent impairment compensation is $220,000, where 'D' is the number derived by expressing the degree of permanent impairment as D%. (2A) To the extent to which the injury results in permanent impairment of the back, the amount of permanent impairment compensation calculated in accordance with subsection (2) is to be increased by 5%. Note: A person suffers 10% permanent impairment. Under subsection (2), the amount of permanent impairment compensation to which he or she is entitled is $13,750 (10 × $1,375). If the whole of the impairment is to the back, the compensation payable in relation to the back will be the whole $13,750. Under this subsection, that $13,750 will be increased by 5%, yielding $14,437.50. Note: A person suffers 50% permanent impairment. Under subsection (2), the amount of permanent impairment compensation to which he or she is entitled is $123,750 ($85,250 + (10 × $3,850)). If two-thirds of the impairment is to the back, the compensation payable in relation to the back will be two-thirds of $123,750, or $82,500. Under this subsection, that $82,500 will be increased by 5%, yielding $86,625. The total compensation payable for the impairment will therefore be $127,875. (3) The amount of permanent impairment compensation is to be calculated under this section as it was in force at the date the injury was received." " 66B No proceedings to enter up award on agreement for compensation (1) When a worker agrees to receive an amount of permanent impairment compensation or pain and suffering compensation, the Commission is not to entertain proceedings for entry of an award to give effect to the agreement unless the proceedings also relate to some dispute in connection with the worker's claim for compensation under this Act. (2) The regulations may prescribe exceptions to this section. (3) The regulations may make provision for or with respect to: (a) requiring an application referring a matter to the Commission to be accompanied by evidence (in the form of a certificate or other information provided for by the regulations) that the proceedings are not prevented by this section from being entertained by the Commission, and (b) preventing the acceptance for lodgment [sic] of an application not accompanied by any evidence required by the regulations to accompany it." " 68B Deductions for previous injuries and pre-existing conditions-operation of sections 15, 16, 17 and 22 (1) When determining the compensation payable in respect of permanent impairment for the purposes of the apportionment of liability under section 22, there is to be no deduction under section 323 of the 1998 Act for any proportion of the impairment that is due to an injury in respect of which liability is to be apportioned (but without affecting any deduction under that section for any proportion of the impairment that is due to any other injury or that is due to any pre-existing condition or abnormality). (2) When determining the compensation payable by an employer in a case in which section 15 applies (disease of such a nature as to be contracted by a gradual process), section 323 of the 1998 Act applies to that compensation subject to the following: (a) there is to be no deduction under section 323 of the 1998 Act for any proportion of the permanent impairment that is due to the worker's employment in previous relevant employment (as defined in paragraph (b)) except any such proportion for which compensation under this Division (as in force at any time) or section 16 of the former Act has been paid or is payable, (b) for the purposes of paragraph (a), 'previous relevant employment' is employment to the nature of which the disease was due by a previous employer who is liable under section 15 to contribute in respect of the compensation being determined (or who would be so liable if the requirement to contribute were not limited to employers who employed the worker during a particular period), (c) in the case of permanent impairment of the back, neck or pelvis, a reference in this subsection to previous relevant employment is limited to employment after the commencement of this Act. (3) When determining the compensation payable by an employer in a case in which section 16 applies (an injury that consists in the aggravation, acceleration, exacerbation or deterioration of a disease), section 323 of the 1998 Act applies to that compensation subject to the following: (a) there is to be no deduction under section 323 of the 1998 Act for any proportion of the impairment that is due to the worker's employment in previous relevant employment (as defined in paragraph (b)) except any such proportion for which compensation under this Division (as in force at any time) or section 16 of the former Act has been paid or is payable, (b) for the purposes of paragraph (a), 'previous relevant employment' is employment that was a substantial contributing factor to the aggravation, acceleration, exacerbation or deterioration by a previous employer who is liable under section 16 to contribute in respect of the compensation being determined (or who would be so liable if the requirement to contribute were not limited to employers who employed the worker during a particular period), (c) in the case of permanent impairment of the back, neck or pelvis, a reference in this subsection to previous relevant employment is limited to employment after the commencement of this Act. (4) When determining the compensation payable by an employer in a case in which section 17 applies (loss or further loss of hearing), section 323 of the 1998 Act applies to that compensation subject to the following: (a) there is to be no deduction under section 323 of the 1998 Act for any proportion of the impairment that is due to the worker's employment in previous relevant employment (as defined in paragraph (b)) except any such proportion for which compensation under this Division (as in force at any time) or section 16 of the former Act has been paid or is payable, (b) for the purposes of paragraph (a), 'previous relevant employment' is employment to the nature of which the disease was due by a previous employer who is liable under section 17 to contribute in respect of the compensation being determined (or who would be so liable if the requirement to contribute were not limited to employers who employed the worker during a particular period)." The Guidelines 21 Section 376 of the Act (including as amended in 2006) authorises the Authority (a reference to the WorkCover Authority of NSW) ("WorkCover") to issue guidelines with respect to the assessment of the degree of permanent impairment of an injured worker as a result of an injury. Pursuant to that power, WorkCover issued guidelines referred to as "WorkCover Guides for the Evaluation of Permanent Impairment" (hereinafter "WorkCover Guides"), the first edition of which was issued in December 2001. The WorkCover Guides are, expressly, based on the American Medical Association's Guides to the Evaluation of Permanent Impairment, 5th Ed ("AMA5"), which are described in the WorkCover Guides as "the most authoritative and widely used source for the purpose of evaluating permanent impairment". 22 The introduction to the WorkCover Guides includes the following: "Assessing permanent impairment involves determining · whether the claimant's condition has resulted in impairment, · whether the condition has reached Maximum Medical Improvement (MMI), · whether the resultant impairment is permanent, · the degree of permanent impairment that results from the injury, and · the proportion of permanent impairment due to any previous injury, pre-existing condition or abnormality, if any." (Exhibit C, p 6.) 23 Assessments are only to be conducted when the Medical Assessor considers that the degree of permanent impairment of the injured worker is fully ascertainable, which necessarily means that the person has obtained Maximum Medical Improvement. 24 The WorkCover Guides also deal with the necessity to deduct, from the assessment of permanent impairment, the amount due to any pre-existing condition or injury. The WorkCover Guides are in the following terms: "(AMA5 section 1-6 p 11) In assessing the degree of permanent impairment resulting from the injury, the assessor is to indicate the proportion of WPI due to any previous injury, pre-existing condition or abnormality. This proportion is known as 'the deductible proportion'. If this amount is difficult or costly to determine, the assessor should indicate this in the report. In this case, for the injury now being assessed, the deduction is 10% of the impairment, unless this is at odds with the available evidence…." (Exhibit C, p 11.) 25 The spine (excluding spinal cord injury) is dealt with in chapter 4 of the 1st edition of the WorkCover Guides (Exhibit C). The WorkCover Guides describe the AMA5 chapter 15 approach as two methods of assessment: the diagnosis-related estimates method; and the range of motion method. The WorkCover Guides require utilisation of the diagnosis-related estimates (DREs), which method relies especially on evidence of neurological deficits and less commonly on adverse structural changes. "Using this method, DREs are differentiated according to clinical findings that can be verified by standard medical procedures…. If surgery has been performed, the outcome of the surgery as well as structural inclusions must be taken into consideration when making the assessment." (Exhibit C, p 24.) 26 The WorkCover Guides make clear that the range of motion method in AMA5 should not be used. The WorkCover Guides set out a table (Table 4.1), which summarises the diagnosis-related estimate category (referrable to AMA5) for all areas of the spine. 27 The WorkCover Guides stress the need for a comprehensive, accurate history; a review of all pertinent records available at the assessment; a comprehensive description of the individual's current symptoms and their relationship to daily activity; a careful and thorough physical examination; and all findings of relevant laboratory, imaging, diagnostic and ancillary tests available at the assessment. "Imaging findings that are used to support the impairment rating should be concordant with symptoms and findings on examination. Table 4.2 of the WorkCover Guides, 1st edition, sets out a pro-forma history of spinal complaint that may be used for the purposes of obtaining an accurate and comprehensive history." 28 Lastly, in terms of relevance to these proceedings, the 1st edition of the WorkCover Guides expresses the view that the AMA5 tables do not adequately account for the effect of surgery upon the impairment rating for certain disorders of the spine. The WorkCover Guides then prescribe (Table 4.4) additional ratings which should be combined with the rating determined using the DRE method where an operation for an intervertebral disc prolapse or spinal stenosis has been performed and where there is a residual radiculopathy following surgery. (Radiculopathy is a condition or disease involving the spinal nerve root.) 29 In October 2006, the 2nd edition of the WorkCover Guides was published, also pursuant to s 376 of the Act. This edition was effective on and from 1 November 2006. As one would expect, there were few, if any, changes to the approach outlined in the 1st edition. The 2nd edition of the WorkCover Guides repeats a paragraph (in the 2nd edition numbered paragraph 1.12) in the following terms: "The WorkCover Guides are meant to assist suitably qualified and experienced medical specialists to assess levels of permanent impairment. They are not meant to provide a 'recipe approach' to the assessment of permanent impairment . Medical specialists are required to exercise their clinical judgement in determining diagnosis, whether the original condition has resulted in an impairment and whether the impairment is permanent. The degree of permanent impairment that results from the injury must be determined using the tables, graphs and methodology given in the WorkCover Guides and AMA5.…" (Emphasis added.) 30 The chapter dealing with injuries to the spine is in or to the same effect as the 1st edition, although there are additional matters of detail expressed. There are paragraphs in the 2nd edition dealing with the specific interpretation of AMA5 and reinforcing the requirement not to use the range of motion method, but to use only the DRE method. Those definitions, too, are expanded and there are paragraphs dealing with the application of the DRE method and the definition and treatment of loss of sexual function, radiculopathy, multi-level structural compromise and the effect of surgery. The effect of surgery is in or to the same effect as the matters repeated above in the 1st edition. 31 It is therefore necessary to examine the relevant parts of AMA5, the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th edition. Page 11 of AMA5 deals with causation and apportionment analysis. After stating that most jurisdictions have their own methods for calculating apportionment and/or defining it, it states that generally "the most recent permanent impairment rating is calculated, and then the prior impairment rating is calculated and deducted. The remaining impairment rating would be attributed or apportioned to the current injury or condition." It states further: "For example, in apportioning a spine impairment rating in an individual with a history of a spine condition, one should calculate the current spine impairment. Then calculate the impairment from any preexisting spine problem. The preexisting impairment rating is then subtracted from the present impairment rating to account for the effects of the former. This approach requires accurate and comparable data for both impairments." 32 At p 374 of AMA5 (an extract of which is Exhibit B in the proceedings), the principles of assessment are discussed. One of the important elements of the assessment principles is the obtaining of a comprehensive, accurate medical history and a comprehensive description of the individual's current symptoms and their relationship to daily activities. The document is in the following terms: "The history must describe in detail the chief complaint and the quality, severity, anatomic location, frequency and duration of symptoms, including pain, numbness, paresthesias, and weakness. Document exacerbating and elevating factors and the way in which the condition interferes with daily activities. The physician should elicit the history of when and how the conditions started, any precipitating events or factors, and the relationship to any previous spine problems. The history should include the individual's description, in his or her own words, of how the symptoms developed and the assumed cause. In addition, the response to treatment and the results of special studies that have been performed should be described. The physician should either review available roentgenograms and other imaging studies personally or report the findings as being those of another reviewer (based on reports). A review of organ systems and of the general medical history can provide potentially helpful information, including complicating medical problems that can affect the diagnosis, treatment plan, prognosis, disability, etc." 33 Table 15-3, at p 384 of AMA5, is a table setting out the "Criteria for Rating Impairment Due to Lumbar Spine Injury". Table 15-3 Criteria for Rating Impairment Due to Lumbar Spine Injury DRE Lumbar Category I DRE Lumbar Category II DRE Lumbar Category III DRE Lumbar Category IV DRE Lumbar Category V 0% Impairment of the Whole Person 5%-8% Impairment of the Whole Person 10%-13% Impairment of the Whole Person 20%-23% Impairment of the Whole Person 25%-28% Impairment of the Whole Person Clinical history and examination findings are compatible with a specific injury; findings may include significant muscle guarding or spasm observed at the time of the examination, asymmetric loss of range of motion, or nonverifiable radicular complaints, defined as complaints of radicular pain without objective findings; no alteration of the structural integrity and no significant radiculopathy Significant sign of radiculopathy, such as dermatomal pain and/or in a dermatomal distribution, sensory loss, loss of relevant reflex(es), loss of muscle strength or measured unilateral atrophy above or below the knee compared to measurements on the contralateral side at the same location; impairment may be verified by electrodiagnostic findings or or Loss of motion segment integrity defined from flexion and extension radiographs as at least 4.5 mm of translation of one vertebra on another or angular motion greater than 15° at L1-2, L2-3, and L3-4, greater than 20° at L4-5, and greater than 25° at L5-S1 (Figure 15-3); may have complete or near complete loss of motion of a motion segment due to developmental fusion, or successful or unsuccessful attempt at surgical arthrodesis Meets the criteria of DRE lumbosacral categories III and IV; that is, both radiculopathy and alteration of motion segment integrity are present; significant lower extremity impairment is present as indicated by atrophy or loss of reflex(es), pain, and/or sensory changes within an anatomic distribution (dermatomal), or electromyographic findings as stated in lumbosacral category III and alteration of spine motion segment integrity as defined in lumbosacral category IV No significant clinical findings, no observed muscle guarding or spasm, no documentable neurologic impairment, no documented alteration in structural integrity, and no other indication of impairment related to injury or illness; no fractures individual had a clinically significant radiculopathy and has an imaging study that demonstrates a herniated disk at the level and on the side that would be expected based on the previous radiculopathy, but no longer has the radiculopathy following conservative treatment history of a herniated disk at the level and on the side that would be expected from objective clinical findings, associated with radiculopathy, or individuals who had surgery for radiculopathy but are now asymptomatic or or or or fractures: (1) greater than 50% compression of one vertebral body without residual neurologic compromise fractures: (1) greater than 50% compression of one vertebral body with unilateral neurologic compromise fractures: (1) less than 25% compression of one vertebral body; (2) posterior element fracture without dislocation (not developmental spondylolysis) that has healed without alteration of motion segment integrity; (3) a spinous or transverse process fracture with displacement without a vertebral body fracture, which does not disrupt the spinal canal fractures: (1) 25% to 50% compression of one vertebral body; (2) posterior element fracture with displacement disrupting the spinal canal; in both cases, the fracture has healed without alteration of structural integrity 34 From pp 385 and following, AMA5 sets out the methods by which one applies Table 15-3 by use of examples. 35 The Guidelines have been repeated in the above detail, because it is the submission of the defendants (and the approach of the Medical Appeal Panel) that the assessment of the WPI is "objective". As it is used in the submission, the term "objective" means the categorisation (and consequential assessment) is performed without regard, or without significant regard, to the effect of the injury on the daily activities of the person being assessed. 36 Adapting the situation currently before the Court, on the above submission, a person, who suffers an injury of a kind suffered by Mr Cameron up to and including 1993, who, after a laminectomy and spinal fusion, is able to perform all normal daily activities would be classified as DRE Lumbar Category IV or DRE Lumbar Category V (assuming radiculopathy). On that submission, one, who was able to perform full-time duties (or full-time duties with some care and/or restriction) would be entitled to a whole person impairment of between 20 and 28%. The above, of course, assumes that the injury occurred as a workplace injury. Subject to the operation of s 68B of the Workers Compensation Act, any subsequent incapacitating injury to the same area would receive no, or no significant, WPI assessment. 37 In the current circumstances, it is the submission of the defendant (accepted by the Medical Appeal Panel) that the pre-existing injuries of Mr Cameron (i.e. prior to the workplace injury of 14 April 2004) are required to be categorised as either DRE Lumbar Category IV or DRE Lumbar Category V, even though full-time work was performed thereafter. As a consequence of which, the workplace injury, which aggravated the pre-existing injury and caused an incapacity for work, could result in a whole person impairment of a maximum of 8% (i.e. the difference between 20%, the lowest percentage in DRE Category IV, and 28%, the highest percentage in DRE Category V). In this Appeal Assessment, the difference resulted in a 6% WPI from the later injury. Yet neither AMA5 nor the WorkCover Guides deal expressly with the method of calculation of pre-existing injury, and, unlike the requirement in relation to the assessment of WPI for workplace injuries (s 322), there is no statutory requirement to have or follow WorkCover Guides in assessing pre-existing injuries (s 323 of the Act and s 68B of the Workers Compensation Act). The Reconsideration Decision 38 There is no challenge, in these proceedings, to the decision of Ms Stephens of 27 January 2006. There is a challenge to the decision of Mr Wormald of 5 February 2007. The reconsideration decision has an effect in two quite different ways. First, it is a decision to reconsider the decision of 27 January 2006. Secondly, having granted the application for reconsideration, the delegate of the Registrar grants leave to appeal. (Leave to appeal is used here to refer to the satisfaction of the "gateway" required before the appeal may proceed.) 39 The rationale for the grant of reconsideration is, in turn, on two bases. In [7] of the decision of 5 February 2007 (the Second Registrar's Decision), the delegate of the Registrar notes that the Registrar who made the determination of 27 January 2006 (the First Registrar's Decision) has resigned her position and is not able to deal with the reconsideration application and proceeds to determine the application for reconsideration. There is no analysis in relation to that aspect. Secondly, the Second Registrar's Decision takes the view, notwithstanding its own injunction not to act as a review of the First Registrar's Decision, that there was error in the First Registrar's Decision, based upon a failure by the Registrar to understand that the Original Assessment was flawed in that it modified the post-workplace injury WPI assessment to take account of the surgical procedure. 40 As has been noted already, it is conceded in these proceedings before the Court, that the inclusion in the WPI assessment of 2% to take account of the surgical procedure was not an error in the Original Assessment. The Second Registrar's Decision that, in that regard, error existed in the Original Assessment was manifestly wrong. 41 As to the grant of leave to appeal, the Second Registrar's Decision dealt with the proper interpretation of s 327(4) of the Act and a submission of or on behalf of Mr Cameron based upon the judgment of the Supreme Court in Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission [2005] NSWSC 1260 at [24]. The Registrar cited Summerfield v Registrar of the Workers Compensation Commission [2006] NSWSC 515 (per Johnson J) and then extracted the following two passages from the judgment of the Court of Appeal in Campbelltown City Council v Vegan & Ors [2006] NSWCA 284. They were: "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." (Per Handley JA at [8].) And "… 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." (Per Basten JA at [133].) 42 The Second Registrar's Decision expresses the view that the appeal by Brookvale Tyres, which the delegate of the Registrar was then purportedly considering, was, "on its face, valid and apparently credible, and cannot be dismissed as patently untenable or colourable." (Second Registrar's Decision at [43].) 43 The Second Registrar's Decision does not discuss whether the provisions of s 327(4) of the Act, as amended in 2006, were applicable. The Power to Reconsider 44 The effect of s 378 of the Act, as inserted in the amendments in 2006, is arguably retrospective. It operates to allow reconsideration of an assessment for which the appeal period has already expired (the period for which, in present circumstances, would be 28 days after the medical assessment). Nevertheless, s 378 is procedural and, by express provision, applies to decisions made before the commencement of the section: see Maxwell v Murphy [1957] HCA 7; (1957) 96 CLR 261; clause 6 of schedule 4 of the Workers Compensation Legislation Amendment (Miscellaneous Provisions) Act 2005. The section allows a reconsideration of the First Registrar's Decision. 45 The Second Registrar's Decision implicitly refers to the difficulty in the construction of the provisions of s 378 but does not deal with its resolution. Subsection 378(1) allows the Registrar, an approved medical specialist or an Appeal Panel to reconsider any matter that has been dealt with by the Registrar, the approved medical specialist or the Appeal Panel. The use of the definite article to qualify approved medical specialist and Appeal Panel, where second occurring, requires a reconsideration by the same AMS or Appeal Panel as made the original decision. While the definite article is used to qualify "Registrar" each time the term is used in the subsection, it seems that the preferable construction is that the same person is to exercise the powers, under s 378 of the Act, as exercised the powers originally. 46 The difficulty with such a construction is that the definite article qualifies the Registrar each occasion that the word occurs. This, however, is because there is only one Registrar. That it is the same person that is required to reconsider it as made the original decision is supported by the ordinary meaning of the term "reconsider". The Macquarie Dictionary defines the term as "1. To consider again. 2. To consider again with a view to a change of decision or action." The Oxford English Dictionary defines the term "reconsider" in the following way: "1. To consider (a matter or thing) again. … b. To consider (a decision, etc.) a second time, with a view to changing or amending it if now disapproved of; to rescind, alter." 47 The Second Reading Speech adds little to the wording of the section, but seems to confirm the requirement that it be reconsidered by the same person as issued the original decision. It says: "To lessen the need for formal appeal or review and to expedite resolution of matters the registrar, approved medical specialists and medical appeal panel are each given an additional power to reconsider their decisions provided that such reconsideration takes place within two months of a referral. Such a reconsideration power will allow, for example, an approved medical specialist to reconsider his or her decision, taking into account documentation that was available at the time but was inadvertently overlooked or was not referred on by the registrar. (Emphasis added.) 48 The Second Registrar's Decision (at [7]) seems to acknowledge the necessity to have the original decision-maker consider the issues again and then, it seems, relies upon the doctrine of necessity on the basis that the original decision-maker has retired. 49 The doctrine of necessity, usually utilised in circumstances of an application relating to the bias of a tribunal or decision maker, has very restricted capacity. It applies to allow a decision maker, who would otherwise be disqualified, to hear and decide a case because no other person has the capacity so to do. Its usage is very restricted: see Builders Registration Board (QLD) v Rauber (1983) 57 ALJR 376 at 386; Australian National Industries Ltd v Spedley Securities Ltd (1992) 26 NSWLR 411 at 421 et seq and at 433 et seq (per Kirby P and Mahoney JA respectively); Laws v Australian Broadcasting Tribunal [1990] HCA 31; (1990) 170 CLR 70 at 88-89 (per Mason CJ and Brennan J). 50 The difficulty with the operation of the doctrine of necessity is that it assumes that the decision maker, other than for the reason for which it is alleged the decision maker is disqualified, is otherwise authorised to make the decision in question. If the reference to "Registrar", with the definite article, were to be construed in the same way as seems to be the intention in relation to the reference to both AMS and the Appeal Panel, then it is only the person who made the original decision that is authorised to reconsider it. 51 The alternative construction is that the Registrar is entitled to reconsider it. On that construction, every decision of a delegate of the Registrar is a decision of the Registrar. However, the construction does not sit comfortably with the use of the definite article, insofar as it applies to an AMS and an Appeal Panel. It would mean that the provisions of s 378 operated differently in relation to the Registrar than it did in relation to the other two classes of decisions. Given that there is only one Registrar, it may be that the Registrar is taken to have made every decision of a delegate thereof and that therefore the Registrar is capable of "reconsidering" such a decision. It is unnecessary to determine this question finally. Nevertheless, it is at least strongly arguable that another delegate of the Registrar does not have the authority to reconsider the earlier-made decision of the Registrar or an earlier delegate. 52 No party has raised the issue of whether the satisfaction of the Registrar, pursuant to s 327(4) of the Act, is a "decision" of the Registrar for the purpose of s 378 of the Act: see s 378(6) and cf ss 122(4), 284, 290(6)(c), 297, 304B, 317, 329 and 357. 53 The more fundamental question that arises from the Second Registrar's Decision is the application by the Registrar's delegate of the unamended terms of s 327(4) of the Act. Assuming, without deciding, that the Registrar had authority to reconsider the refusal to grant leave, the second Registrar's grant of leave was predicated on the basis that, as stated, the delegate applied a test which was whether a ground of appeal exists for the purpose of s 327(4) of the 1998 Act: see [39] of the Second Registrar's Decision and the reference in paragraphs [41], [42] and [43] to the tests adumbrated in Campbelltown City Council v Vegan, supra. 54 Having determined that it was appropriate to reconsider the refusal of leave earlier made, the delegate of the Registrar was required to determine whether the appeal should proceed. The provisions that applied at the time that determination was required were the provisions of s 327(4), inserted by the amendments in 2006. The alternative is arguable, but was not argued by any party. 55 The amendment to s 327(4) of the Act was inserted at the same time as s 378. The amendments to s 327(4) were inserted by clause [22] of schedule 1 to the Workers Compensation Legislation Amendment (Miscellaneous Provisions) Act 2005 No 113. Schedule 4 to the aforesaid Amending Act provides for savings and transitional amendments and, while certain provisions are given express transitional application (e.g. s 378 applies in respect of decisions made before the commencement of the section), no express saving or transitional provision is made in relation to the amendment to s 327(4) of the Act, which is contained in Part 7 of Chapter 7 of the Act. Not only was s 378 given specific retrospective effect (i.e. as applying to decisions made before the commencement of the section), but the amendments made to s 329 relating to a reconsideration of a matter for medical assessment were also given identical retrospective operation. 56 The amendments made to s 327(4) of the Act are procedural in effect. Ordinarily, the amended provision would apply immediately to any application or appeal, whether the application was made before or after the promulgation of the amendment to the section. The complication that arises with this amendment is that the Second Registrar's Decision is not an initial determination of whether the appeal should proceed, but a reconsideration of the function earlier performed. 57 Notwithstanding the doubts arising from that circumstance, counsel for Mr Cameron submits, and Brookvale Tyres admits, that, at the time of the reconsideration, the question before the Registrar's delegate was the question posed by s 327(4), as amended in 2006. The submission of Brookvale Tyres was: "[15] On 5 February 2007 the first defendant's delegate decided that reconsideration of the first defendant's earlier decision was appropriate and gave detailed reasons…. At that time s 327(4) required the first defendant to be 'satisfied that, on the face of the application and any submissions made to the registrar, at least one of the grounds for appeal specified in sub-section (3) has been made out.' The first defendant was so satisfied for the reasons given and the matter was referred to an MAP." 58 Manifestly, the delegate of the Registrar, in the determination of 5 February 2007, did not address the question as to whether or not he was satisfied that on the face of the application and any submission made, at least one of the grounds had been made out. The Registrar's delegate addressed only the question of whether or not the ground "existed". In so doing, the Registrar addressed and answered the wrong question. 59 The provisions of s 327(4) do not require the actual existence of a state of facts, namely the making out of a ground of appeal, but require only the satisfaction of the Registrar of that fact. "It cannot be denied that, if the legislature see fit to do it, any event or fact or circumstance whatever may be made a condition upon the occurrence or existence of which the jurisdiction of a court shall depend. But, if the legislature does make the jurisdiction of a court contingent upon the actual existence of a state of facts, as distinguished from the court's opinion or determination that the facts do exist, then the validity of the proceedings and orders must always remain an outstanding question until some other court or tribunal, possessing power to determine that question, decides that the requisite state of facts in truth existed and the proceedings of the court were valid. Conceding the abstract possibility of the legislature adopting such a course, nevertheless it produces so inconvenient a result that no enactment dealing with proceedings in any of the ordinary courts of justice should receive such an interpretation unless the intention is clearly expressed. In the past a tendency may have appeared in the superior courts of common law to adopt constructions of statutes conferring powers on magistrates and others which would result in the withdrawal from their exclusive or conclusive determination matters which we should now think were intended for their decision. But, even then, it must not be forgotten, that this tendency was manifested in proceedings by certiorari and not in prohibition. When prohibition is based upon want of jurisdiction it means that the proceedings are coram non judice , that a judgment or order, when given or made, would be void." ( Parisienne Basket Shoes Pty Ltd v Whyte [1938] HCA 7; (1938) 59 CLR 369 at 391-392, per Dixon J.) 60 Section 327(4) does not make the arguability, existence or success of the ground of appeal, objectively determined, the criterion for the appeal to proceed. It makes the satisfaction of the Registrar the criterion. The satisfaction of the Registrar is that at least one of the grounds of appeal has been made out. 61 In Riverina Wines Pty Ltd v Registrar of the Workers Compensation Commission of NSW [2007] NSWCA 149, Campbell JA, discussing the reasons for judgment of Handley JA and Basten JA in Campbelltown City Council v Vegan, supra, said: "Even so, both the formulation of Handley JA and of Basten JA require the Registrar to form an opinion that does not go as far as deciding that the ground is actually made out. In my view, both formulations are correct in that respect. To decide that a ground of appeal ' exists ' is not the same as deciding that the ground of appeal has actually been made out. A ground of appeal is a statement of a contention one wishes to make in the course of an appeal, as a reason why the appeal should succeed. A ground of appeal can ' exist ' if it is a contention of that type, made in circumstances where there is a sufficiently realistic prospect of the ground being made out. And in deciding whether the prospect of the ground being made out is ' sufficiently ' realistic, one turns to the context in which, and purpose for which, the question is being asked. In the context of this particular piece of legislation, deciding that the ground exists involves the Registrar forming a view that the ground of appeal has enough substance to warrant the appeal proceeding." ( Riverina Wines , supra, per Campbell JA at [76].) 62 As earlier stated, the satisfaction of the Registrar does not determine the ground of appeal. The Registrar determines whether an appeal should proceed. But as is made clear by Campbell JA in Riverina Wines, supra, the satisfaction that "the ground is made out" is significantly different from (and certainly not the same as) a satisfaction that "the ground of appeal exists". Further, the test "made out" is a more onerous one than the test "exists", and a satisfaction as to the latter would not include the former. 63 As stated by Jordan CJ: "I quite agree that the mere fact that a tribunal has made a mistake of law, even as to the proper construction of a statute, does not necessarily constitute a constructive failure to exercise jurisdiction: R v Minister of Health [1939] 1 KB 232 at 245-246. But there are mistakes and mistakes; and if a mistake of law as to the proper construction of the statute investing a tribunal with jurisdiction leaves it to misunderstand the nature of the jurisdiction which it is to exercise, and to apply 'a wrong and inadmissible test': Estate and Trust Agencies (1927) Ltd v Singapore Improvement Trust [1937] AC 898 at 917; or to 'misconceive its duty', or 'not to apply itself to the question which the law prescribes': R v War Pensions Entitlement Appeal Tribunal (1933) 50 CLR 228 at 242-243; or 'to misunderstand the nature of the opinion which it is to form': R v Connell (1944) 69 CLR 407 at 432; in giving a decision in exercise of its jurisdiction or authority, a decision so given will be regarded as given in a purported and not a real exercise of jurisdiction, leaving the jurisdiction in law constructively unexercised, and the tribunal liable to issue of a prerogative writ of mandamus to hear and determine the matter according to law: R v Board of Education [1910] 2 KB 165." ( Ex parte Hebburn Ltd v Kearsley Shire Council (1947) 47 SR(NSW) 416 at 420; (1947) 64 WN(NSW) 107 at 108, per Jordan CJ with whom Davidson and Street JJ concurred.) 64 The judgment of Jordan CJ recited above was cited with approval by Aickin J in R v Toohey; Ex parte Northern Land Council [1981] HCA 74; (1981) 151 CLR 170 at 268 and by Brennan J (as he then was) in Public Service Association of South Australia v Federated Clerks' Union of Australia (SA) [1991] HCA 33; (1991) 173 CLR 132 at 143-144. 65 As a consequence of the application of the foregoing (together with the conclusion that the delegate of the Registrar misconceived his duty, did not apply himself to the question which the law prescribes, applied a wrong and inadmissible test and misunderstood the nature of the opinion that he was to form), the "satisfaction" under s 327(4) of the Act was only a purported satisfaction and the jurisdiction required to be exercised by s 327(4) of the Act remains constructively unexercised. There is an error of law and an error of jurisdiction. Prerogative writ, or orders in the nature of prerogative writ, will issue. "If such an administrative tribunal falls into an error of law which causes it to identify a wrong issue, to ask itself a wrong question, to ignore relevant material, to rely on irrelevant material or, at least in circumstances, to make an erroneous finding or to reach a mistaken conclusion and the tribunal's exercise or purported exercise of power is thereby affected, it exceeds its authority or powers. Such an error of law is jurisdictional error which would invalidate any order or decision of the tribunal which reflects it." ( Craig v South Australia [1995] HCA 58; (1995) 184 CLR 163 at 179.) 66 Further, the above principle relates to jurisdictional error. Because of the provisions of s 69 of the Supreme Court Act 1970 (including the broadening of the definition of error on the face of the record in s 69(4) thereof), certiorari will issue out of the Supreme Court for error of law on the face of the record, including the reasons for decision. Such an error should be an error upon which the judgment is based and it must be an error of a kind that affects the task undertaken by the tribunal. 67 In the current proceedings, the application of the wrong test and the satisfaction of the Registrar at a lower standard than that required by the provisions as they existed at the time of the exercise, necessarily involves the proposition that the wrong exercise of the jurisdiction conferred by s 327(4) of the Act has affected the task undertaken by the Registrar through his delegate. 68 Further, the Registrar lacks the authority to determine questions of law authoritatively, or bindingly, or to make an order or decision otherwise than in accordance with the law. As earlier stated, the determination that, as a matter of law, the WPI could not include an adjustment for the surgery undertaken prior to the workplace injury, was an error. It was an error of principle and law in the proper construction of the Act and the function of the AMS under the Act. The Challenge to the Appeal Certificate 69 Given the conclusion reached by the Court that the Registrar, through the delegate, has not, pursuant to the terms of s 327(4) of the Act, satisfied himself that at least one of the grounds for appeal has been made out, the appeal could not have proceeded and the Medical Appeal Panel had no jurisdiction to proceed with the appeal. 70 Further, Mr Cameron submits that the Appeal Certificate is vitiated by two independent errors of law. First, the Medical Appeal Panel was confined in its jurisdiction to the correction of an error identified in the Original Certificate and/or the reasons therefor. Secondly, the Medical Appeal Panel was wrong, in law, in the method that it adopted for the ascertainment of the pre-workplace injury impairment. 71 The AMS came to a conclusion, already outlined, that there was a 16% whole person impairment. The reasons for that assessment were expressed at p 6 (p 35 of the Affidavit of Matthew Berringer of 5 July 2007), which, after stating the basis of the initial assessment of 22% WPI (post-injury) plus an additional 2% to take account of the effect of the surgery, says: "His condition since the subject injury has evidently been similar to what I would regard as that which follows 'unsuccessful' surgery. I believe it would be appropriate to deduct 33 1/3% (one-third) of his current impairment figure on the basis that before the subject injury this man would already have fallen into DRE Category IV by virtue of his previous surgery (although prior to 14 April 2004 the result was evidently 'successful')." 72 Essentially, the Medical Appeal Panel saw its task as one "to conduct a review de novo of the Original Assessment. The Panel is free to conduct a review on the basis of the material properly before it, without the need to make a finding as to the existence of an error falling within an available ground of appeal and without being confined to the correction of that error." (Reasons of Appeal Panel [33] Affidavit of Berringer p 195.) 73 Section 328(2) provides that an appeal to the Medical Appeal Panel is "to be by way of review of the original medical assessment". Section 327(3) provides that the grounds of appeal, relevantly, are that the Original Assessment was made on the basis of incorrect criteria or that the medical assessment certificate contains a demonstrable error. 74 The Medical Appeal Panel, in this matter, considered itself bound by the reasons for judgment of the trial judge in Campbelltown City Council v Vegan and not by the comments of Basten JA on appeal, the Panel taking the view that the comments of Basten JA, confining the appeal to demonstrable error, were obiter. In the reasons for judgment of Handley JA in Campbelltown City Council v Vegan, supra, his Honour came to a concluded view the effect of which, it has been said, is inconsistent with the view of Basten JA to which reference has already been made. 75 The starting point for any consideration is the terms of the legislation. The legislation prescribes that the appeal is by way of review of the initial medical assessment. Further, the grounds of appeal require, leaving aside fresh evidence provisions, the demonstration of error. With great respect, I agree with Campbell JA that there is no substantive difference between the reasons of Handley JA and Basten JA, except on a question that was not being decided. On that issue, the onus is on the party seeking to satisfy the Registrar that the ground, under the former test, is not untenable or colourable and I do not understand anything said by Basten JA to be to the contrary. 76 In my respectful view, the approach of McClellan CJ at CL in Crean v Burrangong Pet Food Pty Limited [2007] NSWSC 839 is correct. It accords with the view expressed by Hoeben J in Smith v Liquip Services Pty Ltd [2007] NSWSC 687. As expressed by McClellan CJ at CL: "[26] The tentative view expressed by Basten JA has caused some difficulties and this Court has been urged in a number of cases to follow it. In Smith v Liquip Services Pty Ltd & Ors [2007] NSWSC 687 Hoeben J expressed the view that trial judges should follow the tentative approach suggested by Basten JA. (see to the contrary Harrison AssJ in Lukacic v Vickarini Pty Limited & Anor [2007] NSWSC 530). Malpass AssJ in Skillen v MKT Removals Pty Ltd [2007] NSWSC 608 expressed the approach which he believed this Court should take in the following terms: (at ([20]-[25]) 'It would seem to be intended that what is described as a 'review' conferred by the sections (like that which is conferred by the Rules) is, at least in part, in the nature of an appeal. The statutory regime not only limits the grounds of appeal to four categories, but also requires an identification of those that are relied on. The statutory regime does not require the Registrar to address all of the grounds for appeal. It suffices for the Registrar to be satisfied that at least one of them has been made out. If that happens, only then does the appeal proceed to a Panel (which can address and correct error). In this statutory context, it does not seem to me that it was intended that the review be a hearing de novo (a completely fresh hearing at large in which the power of the Appeal Panel may be exercised regardless of error). See, inter alia, Allesch v Maunz [2000] HCA 40; (2000) 203 CLR 172 at 180-181 . I observe also that there may not be a hearing as such (as in this case, it may be determined on the papers) and the Appeal Panel has restricted powers. I prefer the view that the grounds for appeal impose a restraint on the scope of the review that is to be conducted by the Appeal Panel pursuant to s 328. I further take the view that the matters in issue may be further narrowed by that which may arise from submissions made in respect of the grounds for appeal. Even if a different view were to be taken in respect of any of those matters, it seems to me that it would be a denial of natural justice for the Appeal Panel to deal with matters falling either outside the scope of the grounds of appeal or the submissions without first giving the parties the opportunity to be heard concerning them.' [27] As I understand his Honour the approach to the task of the Appeal Panel taken by Malpass AssJ is generally consistent with the approach described by Handley JA. It requires the Appeal Panel to address the elements of any certificate challenged in an appeal and, if it is satisfied that an error has occurred, review the matter and exercise the power in s 328(5) to confirm the certificate or revoke it and issue a new one. In exercising its powers the Panel is required to examine for itself the medical evidence and may receive fresh evidence pursuant to s 328(3). As 328(4) contemplates the Appeal Panel is to undertake its own medical assessment. [28] In the present case although the Appeal Panel cited the judgment of Wood CJ at CL the process it followed was consistent with that described by Handley JA in the Vegan appeal. It proceeded to consider the grounds of appeal, satisfy itself that an error had occurred and then conducted its own assessment having regard to the medical reports before it. … [30] ... I do not understand Basten JA's view to be that all forms of merit review were excluded by the Act. Such a view would not be consistent with s 328(2) which gives a power to 'review', s 328(3) which provides a power to admit fresh evidence and the power to issue a fresh certificate pursuant to s 328(5). By providing that the appeal Panel may conduct its own assessment and issue a new certificate the process contemplated by the section requires the Appeal Panel to arrive at the correct decision on the merits. [31] I accept that Basten JA's 'tentative view' may confine the Appeal Panel's function to reviewing a medical assessment and correcting errors in relation to matters raised by the appellant. However, in so doing it may review the available evidence, including any fresh evidence provided to it in accordance with s 328(2). Understood in this manner Basten JA's view would be consistent with that expressed by Handley JA. The Act provides for merits review, but, of the matters raised by the appellant. This is the approach taken by Malpass AssJ. If I have misunderstood Basten JA's view it seems to me I should follow the approach favoured by Handley JA, and agreed in by McColl JA rather than the tentative view of Basten JA." 77 The comments of Hoeben J in Smith, supra, are in or to the same effect. He said: "[23] The sections dealing with appeals from approved medical specialist are ss 327 and 328: At the time these applications for appeal were brought those sections were in the following form: [His Honour then recites the legislative provisions.] [24] The first defendant made an application to appeal to the Registrar against the assessment of Dr Blake. It made no application in relation to the assessment by Dr Taylor. It relied upon grounds of appeal 327(3)(c) and (d) that the assessment of the AMS was made on the basis of incorrect criteria and that the medical assessment certificate contained a demonstrable error. The plaintiff made an application to appeal to the Registrar in relation to the assessments of both Doctor Blake and Doctor Taylor. He relied upon all four grounds of appeal provided for in s 327(3). [25] The Registrar was apparently satisfied that, on the face of the applications and any submissions made, at least one of the grounds of appeal had been made out. Unfortunately the document recording the Registrar's referral to the Appeal Panel has been lost or no longer exists. The parties were unable to provide a copy to the Court. Accordingly, it is not known in respect of what grounds the matter was referred to the Appeal Panel and on what basis. It is not even clear which appeals were referred to the Appeal Panel. … [52] Quite clearly on the hearing de novo approach advocated by Wood CJ at CL in Vegan at first instance the plaintiff's ground of appeal 3 must fail. A final decision as to which approach is correct must await further consideration by the Court of Appeal. That having been said, it seems to me that it is a bold step for a first instance judge to entirely disregard obiter remarks by a Judge of Appeal, particularly where that judgment has been agreed to by another Judge of Appeal. This is the case even where those remarks are but 'a tentative view' [53] It seems to me that the approach suggested by Malpass As J has considerable force. I agree that the grounds of appeal impose a restraint on the scope of the review to be conducted by the Appeal Panel. Nevertheless, the task of the Appeal Panel as set out in s 328(2) is to conduct the appeal 'by way of review of the original medical assessment'. It is also of significance that the appeal panel is a specialist panel made up of an arbitrator and two medical specialists. Taking that into account and the concept of 'review' in s 328(2) it would be unduly restrictive to constrain the functions of an Appeal Panel in the way described by Kirby J in Vetter v Lake Macquarie City Council . It seems to me that once error of the necessary kind has been identified that the Appeal Panel can exercise its particular expertise to correct that error which may involve fact finding depending on the nature of the error identified." 78 On the basis of these comments, the approach to be undertaken by a Medical Appeal Panel is to identify an error raised by the appellant, determine whether the error existed, and if so, to assess, on all of the material before the Panel, the whole person impairment without the error it has found. On any analysis, it is not, as stated in the reasons of the Panel, to decline to consider whether an error exists. Further, it is required to make a positive finding as to the existence of an error. The Registrar is the "gatekeeper" but does not finally determine, or objectively determine, the existence of error. Further, the appeal is not a hearing de novo of the Original Assessment without regard to whether an error has occurred or without regard to the Original Assessment. In that regard, the Medical Appeal Panel misunderstood its task, asked itself the wrong question and misconstrued its power. 79 It is submitted that an understanding of the entirety of the reasons of the Medical Appeal Panel discloses that, however it approached the task before it, it took the view that the method of calculation of WPI in the Original Assessment was an assessment on the basis of incorrect criteria or an assessment which contained a demonstrable error. 80 Jurisdictional error of the kind referred to in the previous discussion of the Second Registrar's Decision (which discussion is applicable to the misunderstanding by the Medical Appeal Panel of the task before it) is not saved by a proviso suggesting that, notwithstanding jurisdictional error, no substantial injustice has occurred. Embarking on a task, which is not the task authorised by the Act, vitiates the task. While discretionary considerations may arise as to whether the Court would, in such a scenario, issue orders, the question does not here arise because, for the reasons already adumbrated relating to the task of the Registrar, orders will issue. 81 Notwithstanding that approach, it is necessary to examine the last matter raised by Mr Cameron. The commencement point for any such analysis is the terms of the Act. The Act requires the medical assessment to measure "permanent impairment", which is not a term defined by the Act. As recited, "incapacity" is defined to include a disfigurement "sufficient to affect the earning capacity of a worker or a worker's opportunities for employment". Further, the purpose of the Act is to provide injured workers and their dependants with income support during incapacity and payment for permanent impairment. "Impairment" in this context normally refers to a disorder in structural function resulting from anatomical, physiological or psychological abnormalities that interfere with normal activities. 82 The difference in approach between the AMS and the Medical Appeal Panel is that the Medical Appeal Panel categorises the impairment without regard to whether it interferes with normal daily activities, whereas the AMS estimates the pre-workplace injury impairment having regard to its interference with normal daily activities. 83 Either approach can, hypothetically, give rise to unfairness. The approach of taking no account of interference with normal daily activities, in circumstances where the Act requires the measurement of permanent impairment, would lead to results that are inconsistent with the purpose of the Act, namely, to compensate for that impairment. An injury that does not affect normal daily activities would not, ordinarily, be an impairment or require the need for compensation. Alternatively, it is when, and only when, an injury, objectively assessed, interferes with daily activities that there is any relevant impairment. 84 That does not mean that, in appropriate circumstances, the approach of the Medical Appeal Panel would not be correct. For example, if the circumstances of Mr Cameron were that his pre-workplace injury situation was that he was significantly impaired (i.e. his normal daily activities were interfered with) then the proper measurement would be (or could be) the approach of the Medical Appeal Panel. However, in circumstances such as this, the assessment of the expert appointed initially as the AMS to allocate one-third of his post-workplace injury impairment to the pre-existing injury does not necessarily disclose error. 85 In the circumstances of Mr Cameron, where, on the accepted evidence before the AMS and Medical Appeal Panel, there was no, or no significant, interference with normal daily activities prior to April 2004, an assessment which deducted a whole person impairment in the manner suggested by the Medical Appeal Panel would not be, in fact, an assessment of the "impairment" of Mr Cameron arising from the workplace injury. It would be a wholly hypothetical assessment relating to an injury that has not significantly impaired the person in question. 86 In other words, the method of calculating the pre-injury WPI is a matter for expert assessment. In some circumstances, the logical approach to the assessment is that taken by the AMS. On other occasions, the logical approach is that taken by the Medical Appeal Panel. Neither approach is an error of law. In some circumstances, one or other approach may be an error of fact. In other circumstances, neither approach will be an error of fact. In this case, while not a matter for the Court, the approach of the AMS does not seem to be an error, even of fact. It suffices, for the purpose of dealing with this ground, to reiterate that the approach of the Medical Appeal Panel to the calculation method does not disclose an error of law. Conclusion 87 For all of the above reasons, the Court makes the following orders: (i) The reconsideration of the matters arising under s 327(4) of the Workplace Injury Management and Workers Compensation Act 1998 by the delegate of the Registrar, Mr Wayne Wormald, issued on 5 February 2007 in matter number 6209-2005 between Plymold Seating Pty Ltd trading as Brookvale Tyres and Michael Cameron, be quashed. (ii) The assessment of the Medical Appeal Panel dated 6 March 2007 in matter number 6209-2005, being an appeal by Plymold Seating Pty Ltd trading as Brookvale Tyres in relation to an application for assessment by Michael Cameron, be quashed. (iii) The application by the aforesaid Plymold Seating Pty Ltd trading as Brookvale Tyres, for reconsideration of the refusal of the Registrar to allow to proceed an appeal, by the aforesaid Plymold Seating Pty Ltd trading as Brookvale Tyres, against the medical assessment of 4 November 2005, be remitted to the Registrar to deal with in accordance with law. (iv) Liberty to apply in relation to costs and any consequential order. ********** DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. 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