Court of Appeal Supreme Court New South Wales Medium Neutral Citation: Wright v State of New South Wales [2024] NSWCA 77 Hearing dates: 20 March 2024 Date of orders: 11 April 2024 Decision date: 11 April 2024 Before: Gleeson JA [1]; Mitchelmore JA [2]; Stern JA [3]. Decision: (1) Leave to appeal is granted. (2) The appeal is dismissed. (3) In addition to the orders made by Basten AJ, the State of New South Wales' appeal against the decision of the Medical Assessor dated 16 August 2022 is remitted to the President of the Personal Injury Commission either: (a) For referral under s 329 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) ("Management Act") of Mr Wright's claim of permanent impairment arising out of his injury with a deemed date of 5 December 2018 for further medical assessment; or (b) For referral to a differently constituted appeal panel for hearing under s 328 of the Management Act of the State of New South Wales' appeal. In either case, any further consideration of Mr Wright's claim should be made consistently with the reasons of the Court. (4) Each party is to bear its own costs of the appeal. Catchwords: WORKERS COMPENSATION – Medical assessment – Degree of permanent impairment as a result of an injury – Where medical assessor assessed appellant as having whole person impairment of 19% – Where primary judge found medical assessor had exceeded his statutory jurisdiction having regard to an estoppel arising from the terms of a Certificate of Determination – Whether primary judge erred as to the proper construction of the Certificate of Determination Legislation Cited: Workers Compensation Act 1987 (NSW), ss 2A, 4, 9(1), 9A, 11A, 15(1), 33, 60, 65A(3), 66 Workers Compensation Regulation 2016 (NSW) Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 78, 288, 293, 294, 319, 321(1), 321A, 322, 325, 327, 328, 329 Cases Cited: Be Financial Pty Ltd as Trustee for Be Financial Operations Trust v Das [2012] NSWCA 164 Habib v Radio 2UE Sydney Pty Ltd [2009] NSWCA 231 Secretary, New South Wales Department of Education v Johnson [2019] NSWCA 321 State of New South Wales v Wright [2023] NSWSC 757 Scone Race Club Ltd v Cottom [2024] NSWCA 34 Skates v Hills Industries Ltd [2021] NSWCA 142 State Government Insurance Commission v Oakley (1990) 10 MVR 570; [1990] Aust Torts Reports 81-003 Category: Principal judgment Parties: Paul Wright (Appellant) State of New South Wales (Western Sydney Local Health District) (First Respondent) President of the Personal Injury Commission of New South Wales (Second Respondent) Mr Marshal Douglas, Dr Nicholas Glozier and Dr Douglas Andrews as an Appeal Panel constituted under s 328 of the Workplace Injury Management and Workers Compensation Act 1998 (Third Respondent) Representation: Counsel: D Hooke SC with B McManamey (Appellant) M Allars SC with P Perry (First Respondent) Solicitors: Carroll & O'Dea Lawyers (Appellant) Turks Legal (First Respondent) File Number(s): 2023/245099; 2023/346838 Publication restriction: Nil. Decision under appeal Court or tribunal: New South Wales Supreme Court Jurisdiction: Common Law Citation: [2023] NSWSC 757 Date of Decision: 4 July 2023 Before: Basten AJ File Number(s): 2023/33956 [Note: The Uniform Civil Procedure Rules 2005 provide (Rule 36.11) that unless the Court otherwise orders, a judgment or order is taken to be entered when it is recorded in the Court's computerised court record system. Setting aside and variation of judgments or orders is dealt with by Rules 36.15, 36.16, 36.17 and 36.18. Parties should in particular note the time limit of fourteen days in Rule 36.16.] HEADNOTE [This headnote is not to be read as part of the judgment] The appellant, Mr Wright, commenced employment with Western Sydney Local Health District in August 2012. During the course of that employment, Mr Wright experienced harassment, bullying and other forms of mistreatment, primarily inflicted by his supervisor. Following an incident on 5 December 2018, Mr Wright ceased work due to psychiatric injury. He made a claim against the State of New South Wales (the State) under the Workers Compensation Act 1987 (NSW) (Compensation Act). A dispute arose between Mr Wright and the State concerning the State's liability under the Compensation Act to make weekly payments and to pay medical and related expenses. He filed an Application to Resolve Dispute (ARD1), which was resolved by a Certificate of Determination – Consent Orders (Certificate of Determination) issued by the Workers Compensation Commission, now the Personal Injury Commission (the Commission) under s 294(1) of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) (Management Act) on 6 November 2020. Orders 1 and 5 of the Certificate of Determination agreed that there should be an award in favour of the State in respect of what was described as "the additional injury", being further aggravation and exacerbation of Mr Wright's psychological condition as a result of interactions at work and of his perceptions of his employment and that he was being bullied, subsequent to 5 December 2018 (Post 5 December 2018 Work-related Issues). A second dispute then arose as to the degree of permanent impairment suffered by Mr Wright. Mr Wright filed a second Application to Resolve Dispute (ARD2). The Commission referred the dispute to a Medical Assessor to assess the degree of Mr Wright's permanent impairment resulting from his injury of 5 December 2018. The Medical Assessor issued a Medical Assessment Certificate which assessed Mr Wright as having whole person impairment of 19%. The State appealed, contending that the Medical Assessor had erred as he had included in his assessment impairment which resulted from the "additional injury", as described in the Certificate of Determination, in respect of which the parties had agreed that there should be an award in favour of the State. The Appeal Panel affirmed the Medical Assessment Certificate. The State sought judicial review of the Appeal Panel's decision. The primary judge found the Medical Assessor had exceeded his statutory jurisdiction by taking into account matters that he was required not to take into account, and that the Appeal Panel erred in failing to identify this. Mr Wright appealed against this decision. Mr Wright's application for leave was heard together with the substantive appeal. The Court (Stern JA, Gleeson and Mitchelmore JJA agreeing) held, granting leave to appeal but dismissing the appeal: As to Mr Wright's application for leave to appeal: (1) The matters raised in the grounds of appeal involve issues of principle as to the proper construction of consent orders which impact upon Mr Wright's entitlement to compensation for permanent impairment. In these circumstances, leave to appeal should be granted: [7]. Be Financial Pty Ltd as Trustee for Be Financial Operations Trust v Das [2012] NSWCA 164, considered. As to issue (i) (per Stern JA, Gleeson and Mitchelmore JJA agreeing) (2) The natural meaning of the language the parties used in orders 1 and 5 is that Mr Wright and the State agreed that Mr Wright was not entitled to payments under the Compensation Act in respect of the claimed aggravation and exacerbation of his psychological injury by reason of Post 5 December 2018 Work-related Issues. That flows from the clear terms of order 5, agreeing that there should be an award for the State in respect of the additional injury as alleged and specified in order 1, being further aggravation and exacerbation of Mr Wright's psychological condition by reason of Post 5 December 2018 Work-related Issues. That construction of the orders is supported by the ambit of the dispute between the parties which was resolved by the Certificate of Determination: [76]-[77]. (3) Mr Wright's contention that the primary judge erred as to the proper construction of the Certificate of Determination should be rejected. It necessarily follows that the Appeal Panel erred in their construction of the Certificate of Determination and of the ambit of the estoppel arising therefrom: [80]-[81]. As to issue (ii) (per Stern JA, Gleeson and Mitchelmore JJA agreeing) (4) On what was found to be the proper construction of the Certificate of Determination, it would not have been open to the Medical Assessor to find that any aggravation and exacerbation of Mr Wright's injury, resulting from Post 5 December 2018 Work-related Issues, was itself caused or contributed to by his 5 December 2018 Injury. That issue was resolved by orders 1 and 5 of the Certificate of Determination. Thus, principles of causation had no further work to do. Mr Wright's contention that the primary judge erred in this regard should thus be rejected: [85]-[87]. As to issue (iii) (per Stern JA, Gleeson and Mitchelmore JJA agreeing) (5) It would have been open to the Medical Assessor to make an assessment of Mr Wright's permanent impairment having regard to aggravation and exacerbation of Mr Wright's injury of 5 December 2018 provided that he did not include in that assessment any aggravation and exacerbation which resulted from Post 5 December 2018 Work-related Issues. Had the Medical Assessor done so, there would be no demonstrable error in his decision: [88]. (6) There are several matters in support of the conclusion that the Medical Assessor did not exclude from consideration aggravation and exacerbation of Mr Wright's injury resulting from Post 5 December 2018 Work-related Issues. In these circumstances, as found by the primary judge, the Medical Assessment Certificate contains a demonstrable error. The declaratory relief ordered by the primary judge is appropriate: [91]-[96]. (7) In addition to the declaratory relief granted by the primary judge, an order should be made remitting the matter to the President of the Commission, either for referral of Mr Wright's claim of permanent impairment for further medical assessment under s 329 of the Management Act or for referral of the State's appeal against the decision of the Medical Assessor to a differently constituted appeal panel under s 328 of the Management Act. In either case, any further consideration of Mr Wright's claim should be made consistently with the reasons of the Court. In the latter case, it would be incumbent upon any freshly constituted appeal panel to revoke the Medical Assessor's certificate and then to conduct its own assessment of Mr Wright's permanent impairment and reflect that assessment in a new certificate of assessment: [99]. JUDGMENT 1. GLEESON JA: I agree with Stern JA. 2. MITCHELMORE JA: I agree with Stern JA. 3. STERN JA: In a medical assessment certificate dated 16 August 2022 (the "Medical Assessment Certificate"), given under s 325 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) ("Management Act"), a medical assessor (the "Medical Assessor") certified that the appellant, Mr Wright, suffered from a whole person impairment of 19% resulting from a psychiatric/psychological injury with a deemed date of 5 December 2018 (the "5 December 2018 Injury") arising from his employment by the State of New South Wales (the "State") as a courier driver for the Western Sydney Local Health District. The State sought to appeal that decision but on 7 November 2022, the Appeal Panel of the Personal Injury Commission (respectively the "Appeal Panel" and the "Commission") confirmed the Medical Assessment Certificate. The primary judge upheld the State's application for judicial review of the Appeal Panel's decision: State of New South Wales v Wright [2023] NSWSC 757. Mr Wright now seeks leave to appeal, and to appeal, from that decision. 4. The substantive issue raised by these proceedings is whether, as the State successfully contended before the primary judge, the Medical Assessor exceeded his statutory jurisdiction having regard to an estoppel arising from the terms of a Certificate of Determination – Consent Orders ("Certificate of Determination") of an arbitrator in the then Workers Compensation Commission (now the Commission) dated 6 November 2020. The Certificate of Determination resolved an earlier dispute between Mr Wright and the State as to the State's liability to make weekly compensation payments, and to pay for medical and related expenses, under the Workers Compensation Act 1987 (NSW) (the "Compensation Act"). The primary judge upheld the State's contention and found that the Medical Assessor had exceeded his jurisdiction and that the Appeal Panel was thus in error in confirming the Medical Assessment Certificate under s 328(5) of the Management Act. Neither the second or third respondents took part in the proceedings before the primary judge or on appeal. 5. The primary judge made the following orders: "(1) Set aside the decision of the Appeal Panel of the Personal Injury Commission dated 7 November 2022 and the Certificate of Determination issued by the Commission dated 2 December 2022. (2) Declare that the Appeal Panel erred in law in failing to find that the Personal Injury Commission exceeded its jurisdiction because the medical assessor did not give effect to the estoppel arising from the determination of the Workers Compensation Commission of 6 November 2020, Order 5." 1. Mr Wright's application for leave was heard together with the substantive appeal. 2. The question of leave can be dealt with briefly. The matters raised in the grounds of appeal involve issues of principle as to the proper construction of consent orders which impact upon Mr Wright's entitlement to compensation for permanent impairment. In these circumstances, leave to appeal should be granted: Be Financial Pty Ltd as Trustee for Be Financial Operations Trust v Das [2012] NSWCA 164 at [32]-[39] (Basten JA, Tobias AJA agreeing). 3. For the reasons set out below, however, the appeal should be dismissed. Further, as set out below at [98], in addition to the orders made by the primary judge, an order for remittal should be made in the terms set out at [99] below. Factual and procedural background Background 1. Mr Wright's employment with Western Sydney Local Health District commenced in August 2012. During the course of that employment, Mr Wright experienced harassment, bullying and other forms of mistreatment, primarily inflicted by his supervisor. Following an incident on 5 December 2018, Mr Wright ceased work due to psychiatric injury. After receiving treatment, Mr Wright returned to work on 11 February 2019. He worked reduced hours for a period of approximately six weeks but then, he claims, psychologically deteriorated following further negative interactions with his supervisor and other colleagues. 2. Mr Wright made a claim against the State under the Compensation Act. The first application to resolve a dispute between Mr Wright and the State 1. On 7 September 2020, Mr Wright filed an "Application to Resolve Dispute" ("ARD1"), which, under s 288(1) of the Management Act, referred a dispute to the Commission for determination. That involved completion of a standard form application. Against a list of check boxes under the heading "Matters in Dispute", the following matters were indicated as being in dispute: "Weekly benefits where liability in dispute" and "Medical expenses (where the amount is more than $9,468.10)". That reflects claims that Mr Wright had made for compensation under s 33, and for payment of medical expenses under s 60, of the Compensation Act. In the section of ARD1 headed "Injury Details" the date of injury was given as 9 August 2018 and the "Injury Description / Cause of Injury and Death" was described as: "Psychological injury The Applicant, during the course of his employment was bullied, harassed, subject to an exclusionary alliance and mobbing by his line manager and another co-worker and subject to victimising and unnecessary performance management review and was provided with no managerial support, thereby causing, aggravating, exacerbating and/or precipitating the injury described above. The Applicant initial adjustment disorder into a major depression which required him to be hospitalised twice, thereby exacerbating the state of the original injury described above." 1. Immediately following, in a box which was also identified as "Type of Injury", there was an entry "Aggravation, acceleration or exacerbation or deterioration of disease", also with a deemed date of 9 August 2018. 2. In Annexure A to its reply to ARD1, the State's insurer provided a list of issues in dispute. This stated: "In respect of the injury alleged on 9 August 2018, the respondent relies on the section 78 notice attached to the Application and the section 287A notice attached to the Reply. In respect of this injury, the respondent states that the following issues are in dispute: 1. That the injury arose out of or in the course of the applicant's employment with the respondent as required under section 4 of the Workers Compensation Act. 2. That the applicant's employment with the respondent was the main contributing factor to any disease injury under section 4(b)(i) of the Workers Compensation Act 1987. 3. That the applicant's employment was the main contributing factor to the aggravation, acceleration, exacerbation or deterioration of any disease injury under section 4(b)(ii) of the Workers Compensation Act 1987. 4. In the alternative, that the applicant's psychological injury was caused wholly or predominantly by reasonable action taken or proposed to be taken by or on behalf of the respondent with respect to performance appraisal and discipline and is therefore not compensable under section 11A of the Workers Compensation Act 1987 (WC Act). [There followed paragraphs dealing with the entitlement to weekly payments of compensation under s 33 and payment of medical expenses under s 60 of the Compensation Act.] The respondent notes that the documents attached to the Application suggest that the applicant aggravated his psychological injury on or about 29 February 2020. In respect of this allegation, the respondent states: 10. Prior to the filing of the Application to Resolve a Dispute ("ARD"), the respondent was not aware of any allegation that the applicant had aggravated his psychological injury due to the incident on 29 February 2020. 11. That it objects to any allegation of injury on or around 29 February 2020, in the manner described by the applicant, being relied on by the applicant in the current proceedings on the basis that the allegation has not previously been put to the respondent. 12. That, in the alternative, if the applicant is allowed to rely on injury on or about 29 February 2020, leave will be sought to put in issue section 4(b)(ii) of the Workers Compensation Act 1987. 13. That any incapacity for work from 29 February 2020 is attributable to the alleged aggravation of the applicant's injury on 29 February 2020, and not as a result of the injury on 9 August 2018." (Emphasis in original). 1. On 6 November 2020, under s 294(1) of the Management Act, the Commission issued the Certificate of Determination: "Certificate of Determination – Consent Orders … 1. Amended ARD as follows: under the heading Injury Details by deleting the date of injury appearing there and replacing it with 5/12/18, by placing a tick in the box for "deemed", and adding the following to the words appearing after injury description/cause of injury In addition, in the course of employment subsequent to 5 December 2018, as a result of the applicant's interactions with his supervisors, fellow employees and officers of the defendant, and as a result of his perceptions that his employment was at risk and that he was being bullied, he suffered further aggravation and exacerbation of a psychological condition ("the additional injury"). 2. Award in favour of the applicant for the injury of 5 December 2018 (deemed date, section 4(b) (ii) of the Workers Compensation Act 1987 (the 1987 Act) for the period 6 December 2018 to 6 March 2019, agreed to be thirteen weeks at the rate of $968.91 per week, and for the period 7 March 2019 to 7 November 2019, agreed to be thirty five weeks at the rate of $786.93 3. Award in favour of the respondent in respect of any allegation of incapacity beyond 7 November 2019. 4. Award in favour of the respondent in respect of any entitlement to medical and hospital expenses, subject to notation 2 below. 5. Award for the respondent in respect of the additional injury alleged and specified in Order 1 above. 6. Award for the respondent in respect of any allegation of frank injury, that is injury as defined in section 4(a) of the 1987 Act. Notations: 1. The applicant agrees and acknowledges that beyond 7 November 2019, he has and has had the capacity to earn, in suitable employment (section 32A of the 1987 act) not less than that which he would be earning but for injury. 2. The respondent agrees to pay, upon production of accounts, receipts, or Medicare notice of charge, medical and hospital expenses for treatment of the applicant's psychiatric condition up to the sum of $10,000. 3. The respondent waives any entitlement to recoup payments of sick leave or annual leave paid during the period of the award. 4. The applicant agrees that on receipt of the payments referred to above, he will have received all entitlements to weekly benefits and medical expenses to date in respect of work injury." (Emphasis in original) 1. It is orders 1 and 5 of the Certificate of Determination that are said to give rise to the estoppel, which in turn founds the alleged excess of jurisdiction on the part of the Medical Assessor. 2. Senior Counsel for each of Mr Wright and the State on appeal submitted that Annexure A, extracted at [13] above, applied as regards ARD1, as amended by the Certificate of Determination, to include the "additional injury" defined in order 1 of the Certificate of Determination. It necessarily follows that each of the issues identified in Annexure A were in dispute as regards the 5 December 2018 Injury, and as regards the claimed aggravation and exacerbation of that injury described in order 1 of the Certificate of Determination as the "additional injury". The second application to resolve a dispute between Mr Wright and the State 1. On 20 May 2021, Mr Wright's solicitors wrote to the State's insurer, advising that Mr Wright was claiming compensation under s 66 of the Compensation Act of $48,670 in respect of a psychiatric injury which occurred on 5 December 2018. By letter of 8 September 2021, the State's insurer disputed that Mr Wright's permanent impairment exceeded 15% and thus that he was entitled to compensation having regard to s 65A(3) of the Compensation Act. 2. On 7 April 2022 Mr Wright filed a further "Application to Resolve a Dispute" with the Commission ("ARD2"). Again this involved completion of a standard form. In ARD2 the matter in dispute was identified as: "Lump sum compensation where degree of permanent impairment is in dispute". 1. The "deemed" date of injury was said to be 20 May 2021, the type of injury was said to be "Disease", the place of injury was said to be "Within the environs of the respondent's premises" and the "Injury Description / Cause of Injury and Death" was: "The Applicant has sustained a psychological injury as a result of interpersonal conflict in the course of his employment with the respondent." 1. Mr Wright claimed a total whole person impairment percentage of 19% and a total whole person impairment lump sum of $50,260. 2. In its reply to ARD2, the State's insurer contended: "The ARD pleads the Applicant's injury as occurring on 20 May 2021 (deemed) and describes the injury as follows: The Applicant has sustained a psychological injury as a result of interpersonal conflict in the course of employment with the respondent. In matter number 5068/20, the Applicant and Respondent agreed to an award in respect of any allegation of injury relating to interactions subsequent to 5 December 2018. This is outlined in the Certificate of Determination dated 6 November 2020. The Respondent accepts that the date of injury can be 20 May 2021 for the purposes of the lump sum compensation claim, however, a teleconference is sought to have the allegation of injury in the ARD amended to the following: The Applicant has sustained a psychological injury as a result of interpersonal conflict in the course of employment with the respondent between 20 August 2012 and 5 December 2018. If the Applicant consents to the amended, a teleconference is not required." 1. On 3 May 2022, in response to an email from an employee of the Commission, Mr Wright, through his solicitor, consented to amend the allegation of injury as requested by the State's insurer. Thus, the Commission used the deemed date of injury of "5 December 2018 – deemed (for the period 20 August 2012 to 5 December 2018)" and Mr Wright agreed to this. Referral for medical assessment 1. On 21 June 2022, the dispute was referred by the Commission to the Medical Assessor in the following terms: "1. MEDICAL DISPUTE REFERRED FOR ASSESSMENT (s319 WIM Act) the degree of permanent impairment as a result of an injury (s319(c)) whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality, and the extent of that proportion (s319(d)) whether impairment is permanent (s319(f)) whether the degree of permanent impairment of the injured worker is fully ascertainable (s319(g)) Date of injury: 5 December 2022 – deemed (for the period 20 August 2012 to 5 December 2018 Body part/s referred: Psychiatric/psychological disorder Method of assessment: Whole person impairment 2. BRIEF The brief provided to the medical Assessor includes: 1. the Application and attached documents 2. the Reply and attached documents …". (Emphasis in original). 1. It is common ground that the Referral contained an error in that the date of injury ought to have read 5 December 2018 but that nothing turns on this. Medical Assessment Certificate 1. On 16 August 2022, the Medical Assessor issued the Medical Assessment Certificate under s 325(1) of the Management Act. He identified the details of the matters referred for assessment as: "• Date of injury: 5 December 2018 – deemed (for the period 20 August 2012 to 5 December 2018 • Body parts/systems referred: Psychiatric/Psychological disorder • Method of assessment: Whole Person Impairment". (Emphasis in original). 1. In a section headed "History relating to the injury", the Medical Assessor provided a "Brief history of the incident/onset of symptoms and of subsequent related events" as follows: "The issue at work predominantly related to Mr Wright's manager. He has known her personally because they belonged to the same rugby club. He explained that he used to play and coached in the club, and had been a member for about 20 years. He does not understand why she would pick on him, and described that he was subject to mobbing behaviour, excluded by people because of her, and also repeated passive aggressive behaviour. He reported that he became sick of the constant harassment and had thought about making a complaint in 2015, but then said that it was against his moral belief to do it, especially as they were both belonged [sic] to the same football club. The most significant incident happened in December 2018 and that was when Mr Wright first stopped working. He received treatment and returned to work, but then psychologically deteriorated. He explained there were further problems when he went back to work. He recalled there were changes being made at work, and the drivers were being transferred to Liverpool and he was looking forward to it because it meant he would not be reporting to the same manager. Suddenly management called him and said that his job was gone, he needed to apply for the Liverpool position but the application closed the next Monday. He then discovered that all the other drivers knew they needed to apply in advance, and that again he was the only person being singled out. Mr Wright had two psychiatric admissions, both in early 2020 in St John of God Hospital. He has also been attending a day program in SJOG hospital in the last two years, usually once a week. The program finished about four weeks ago. He said the return-to-work coordinator advised him he should change department [sic] to get away from the manager, he just needed to have a psychiatrist report in support. However, even though he did all that was required, a return to work never happened. He said he was stood down and was told there was no job available for him anymore." 1. In a subsection headed "Subsequent psychological injury", it was noted: "His father passed away in Blacktown Hospital in December 2020. He had prostate cancer. Mr Wright found it difficult to attend for longer than 1 hour, as being in NSW Health makes him anxious due to his workplace experience. This has not produced a new psychological injury." 1. The following was included under a bullet point "Work history including previous work history if relevant": "Mr Wright had been working at Westmead Hospital as a full-time courier and started in 2012. After his injury, he tried to go back to work around April 2019, three hours a day, three days a week. He said it lasted about six weeks. He recalled he had a meeting with a higher manager before returning to work and was told that he would not be reporting to the same manager who bullied him, that he would report to another worker and the higher manager. However, when he started work, the higher manager did not turn up and the other worker did not know anything about the arrangement. The manager who bullied him returned to work, and he said that she continued to bully him through the other workers, for example they claimed he has not done the mandatory training online module. He explained to them that he did it, but later discovered that he needed 95% to pass, so even though he did the module he did not pass it. He said there was still ongoing problem [sic]. She was still harassing him through other people, and eventually he had to stop work." 1. By way of "summary of injuries and diagnoses", the Medical Assessor wrote: "Mr Wright described having developed persisting anxiety and depression, as a result of his employment and interaction with his manager. He described difficulties in returning to work. Since he ceased work with Westmead Hospital, he has not been able to attempt other employment and described chronic functional impairment. Overall, my view is that he developed a Major depressive disorder and his impairment has stabilized. Regarding pre-existing injury, I have not applied a pre-existing impairment deduction on the basis that he has suffered depression and anxiety many years ago. All treatment had been ceased, he returned to full psychological functioning and there is no evidence that the previous history contributed to his current impairment." 1. Under the heading "Evaluation of permanent impairment", when asked to indicate "whether there has been any further injury subsequent to the subject work injury", the Medical Assessor indicated: "No further injury." 1. In the section headed "Reasons for assessment", the Medical Assessor referred to the PIRS table annexed to the Medical Assessment Certificate. This included, against a heading "Employability and Adaptation", that: "Mr Wright has not worked since the subject injury and his anxieties have a major impact on his capacity to work in any environment." 1. Mr Wright was assessed as having whole person impairment of 19%. In making this assessment, the Medical Assessor took into account "The provided reports, Mr Wright's reported history, and mental state examination." The section headed "Reasons for assessment" also included reference to the following: 1. The discussion in Mr Wright's statement of the "return-to-work" problems; 2. Associate Professor Robertson, IME psychiatrist, having diagnosed a chronic adjustment disorder in a report dated 28 May 2019; 3. A further report dated 22 July 2020 from Associate Professor Robertson noting Mr Wright's progress and the major depression diagnosis from the hospital. Associate Professor Robertson's whole person impairment rating in respect of Mr Wright was the same as Dr Hong's; 4. A report dated 19 March 2019 from Ms Raj, psychologist, noting adjustment disorder, depression and anxiety and noting the return-to-work problems; 5. A report dated 18 January 2019 from Dr Smith, IME psychiatrist, stating that Mr Wright had symptoms of a "normal emotion [sic] reaction", that there was no psychiatric diagnosis and that Mr Wright could return to work; 6. Subsequent reports on 18 March and 16 June 2020 from Dr Smith advising that Mr Wright developed an adjustment disorder in 2019 "because he was stuck at home obsessing over what happened at work" and an aggravation of an adjustment disorder during 2019, especially December 2019, "due to decision to relocate position in Liverpool, which required him to reapply for his position and he felt ambushed." Dr Smith then, on 12 July 2021, provided a whole person impairment of 8%; and 7. The Medical Assessor's opinion that Mr Wright's impairment was permanent and fully ascertainable. Proceedings before the Appeal Panel of the Personal Injury Commission 1. As set out above, the State appealed against the decision of the Medical Assessor on the ground that the Medical Assessment Certificate contained a demonstrable error pursuant to s 327(3)(d) of the Management Act. On 5 October 2022, a delegate of the Commission referred the State's application to the Appeal Panel. 2. The key contention of the State on that appeal was that the Medical Assessor assessed Mr Wright's permanent impairment without regard to the fact that the Certificate of Determination dated 6 November 2020 was a determination of the Commission, by consent, that Mr Wright's alleged psychological injury arising from events at work after 5 December 2018 was not compensable. More particularly, the State contended that there was demonstrable error as the Medical Assessor attributed impairment to Mr Wright's injury on 5 December 2018 that had actually resulted from the "non-compensable" injury subsequent to that date. 3. Mr Wright's key contention before the Appeal Panel was that the Medical Assessor had not erred as he assessed the impairment arising from the injury as referred, being the injury with a deemed date of 5 December 2018 for the period 20 August 2012 to 5 December 2018, and did not assess impairment by reference to the "additional injury". 4. By decision of 7 November 2022, the Appeal Panel, constituted by one member and two medical assessors, determined that there was no demonstrable error in the Medical Assessment Certificate and dismissed the State's application. The Appeal Panel had before it all of the documents that were sent to the Medical Assessor and took those into account in making its determination. 5. The Appeal Panel identified (at [10]) that the key issue before it was: "… whether Medical Assessor Hong included in his assessment of the respondent's WPI resulting from the respondent's compensable injury that the parties agree was deemed to have happened on 5 December 2018, any impairment resulting from what occurred in the respondent's employment after he returned to work on 11 February 2019 and if so whether the Medical Assessor erred by doing so." 1. Ultimately, as was accepted by Senior Counsel for Mr Wright on appeal, the Appeal Panel answered the second, but not the first, of the two questions identified in this paragraph. 2. The Appeal Panel found (at [37]) that the Medical Assessor had "correctly assessed the respondent's permanent impairment resulting from the injury the respondent suffered from the events to which he was subject in his employment with the appellant prior to 5 December 2018". As to the effect of the Certificate of Determination, the Appeal Panel found (at [39]) that there were two available constructions of the consent orders: 1. That the circumstances that Mr Wright alleged to have occurred after 5 December 2018 did not occur; or 2. Those circumstances did occur but they did not give rise to any injury separate to what the respondent suffered on 5 December 2018. 1. The Appeal Panel found (at [39]) that the latter construction should be preferred given that the award was given with respect to the "additional injury alleged" (Appeal Panel's emphasis) not an award with respect to any claim for compensation which might have been made as a consequence of such alleged injury. 2. The Appeal Panel's reasons for dismissing the State's appeal included the following: "[41] In arguendo, if the estoppel arising from the consent award in the prior proceedings did not relate to the alleged occurrence of events subsequent to 5 December 2018 or to an alleged injury resulting from those subsequent events, but related to incapacity from an "additional injury" and the need for medical treatment resulting from an "additional injury" or whether an "additional injury" from such events was wholly or predominantly caused by reasonable action taken by the respondent with respect to the matters specified in s 11A of the 1987 Act, in other words the respondent can contend in these proceedings that there was a subsequent "additional injury", then necessarily that "additional injury" did not arise from the same incidents as the incidents from which the injury on 5 December 2018 occurred. In such circumstance, and again this is a hypothetical given what the Appeal Panel has said about the estoppel that did arise from the prior award, s 65(2) of the 1987 Act and s 323(3) of the 1998 Act could not be engaged. However, in such a circumstance, the authority of Johnson and Ozcan would apply such that the Medical Assessor would have been required to apply common law principles of causation to determine the degree of permanent impairment the respondent had from his injury of 5 December 2018. The situation would have been, in such circumstance, that the respondent's condition as a result of his injury on 5 December 2018 was worsened by the "additional injury" and that no part of the worsening of the respondent's condition would have been occasioned if the injury of 5 December 2018 had not occurred. In other words, the worsening of the respondent's symptoms and function consequent to what occurred after 5 December 2018 was causally connected to the injury the respondent suffered on 5 December 2018. [42] Moreover, it is trite that an impairment of a worker can have multiple causes. If the estoppel arising from the consent award in the prior proceedings did not relate to the occurrence of events as alleged by the respondent subsequent to 5 December 2018 or to an alleged injury due to those events, then the situation would be that both injuries, that is the injury of 5 December 2018 and the "additional injury", would have materially contributed to the respondent's impairment, with the predominant contributor, in the Appeal Panel's view, having been the injury of 5 December 2018. In such a hypothetical scenario, the Medical Assessor would have been right to attribute the respondent's 19% WPI from the 5 December 2018 injury. [43] In short, the Appeal Panel considers that the Medical Assessor has not made an error with respect to his assessment of the respondent's permanent impairment from his injury on 5 December 2018. The Medical Assessor has assessed the medical dispute that was referred to him for assessment, being the respondent's permanent impairment from the injury of 5 December 2012 [sic]. But whichever way the matter is analysed, that is if there was "an additional injury" or if subsequent events contributed to the respondent's impairment, the result would be the same." (Footnotes omitted). 1. It is thus apparent that the Appeal Panel dismissed the appeal for two separate and independent reasons: 1. The ambit of the estoppel arising from the Certificate of Determination was limited to precluding Mr Wright from contending that he sustained an injury "separate to what [he] suffered on 5 December 2018" by reason of events subsequent to that date; and 2. Even if an estoppel precluded Mr Wright from contending that there was any incapacity from an additional injury, whether an additional injury was caused by his employment or that the additional injury was not caused by reasonable action taken by or on behalf of the employer (as provided in s 11A of the Compensation Act): 1. Mr Wright could still rely upon common law causation and contend that the aggravation and exacerbation was caused by the injury of 5 December 2018; and 2. Moreover, both injuries would have materially contributed to Mr Wright's impairment and the Appeal Panel considered that the injury of 5 December 2018 was the predominant contributor. Primary judge's key findings 1. There was no dispute before the primary judge that the Certificate of Determination could give rise to an estoppel. The issue was as to the ambit of the estoppel, and as to whether the Medical Assessor had exceeded jurisdiction having regard to the estoppel such that the Appeal Panel's decision suffered from legal error. 2. As submitted by Senior Counsel for Mr Wright on appeal, the primary judge expressed the ambit of the estoppel arising from the Certificate of Determination in slightly different terms at different places in his Honour's judgment: see eg at [22], [40], [45], [51]. However, the key finding in this regard is encapsulated in the primary judge's reasons (at [40]) as follows: "… It followed [from the Certificate of Determination] that a complaint that the conduct of the employer had resulted in further aggravation and exacerbation of a psychological condition arising before 5 December 2018, could not be pursued. It further followed that the medical assessor should have identified and excluded any such aggravation or exacerbation from his assessment of the injury caused by the conduct preceding 5 December 2018." 1. After setting out the Appeal Panel's reasons (at [40]), his Honour said of that paragraph: "[42] Each of these sentences is correct as a matter of fact, but they do not address the employer's contention. The employer submitted that the medical assessor's rejection of the proposition that the worker had suffered any further injury (at par 8g) was in fact a conclusion supported by his earlier finding that the worker's reaction to the death of his father did not cause psychiatric injury. The real issue was how the medical assessor had dealt with a history (which he clearly accepted) that included the worker's response to the employer's conduct when he sought to return to work in February/March 2019. The issue for the Appeal Panel was whether, despite the absence of any discussion by the assessor of that issue, it could be inferred that he had rejected the possibility that the applicant's condition was aggravated or exacerbated by that conduct of the employer." 1. As to this question, the primary judge said: "[51] The effect of orders 1 and 5 in the determination of 6 November 2020 was that the worker did not suffer any further aggravation and exacerbation of his psychological condition as a result of conduct of the employer after 5 December 2018. The history recorded by the medical assessor in his reasons for determination included repeated references to the worker's claims of ongoing bullying and harassment in 2019. There was no suggestion that the medical assessor disregarded those claims, nor that he determined that they had no effect in aggravating or exacerbating the worker's psychological condition. … [55] The remaining submissions of the worker relied on the proposition that the medical assessor did not make a finding that there had been any further injury in the period after 5 December 2018. That the assessor did not make such a finding in terms may be accepted. However, that submission did not come to grips with the employer's complaint that the worker gave evidence, plainly accepted by the medical assessor, that his existing psychological condition was aggravated by further bullying and harassment in the workplace in February/March 2019. By relying on that aggravation, caused by work-related conduct, the assessor ignored the limitation on the terms of the dispute which he was required to resolve." 1. It followed that the primary judge found the Medical Assessor had exceeded his statutory jurisdiction by taking into account matters that he was required not to take into account, and the Appeal Panel erred in failing to identify this. Notice of appeal 1. Whilst Mr Wright's notice of appeal advances six appeal grounds, as submitted by Senior Counsel for Mr Wright during oral submissions, these contentions resolve into two substantive grounds: 1. The primary judge erred in failing to consider that the effect of orders 1 and 5 in the Certificate of Determination could not amount to any more than that interactions with his supervisors, fellow employees and officers of the State, and the perception that his employment was at risk and that he was being bullied, did not give rise to a separate compensable injury by way of aggravation and exacerbation of a psychological condition (ground 2 in the notice of appeal); and 2. The primary judge erred in failing to apply the settled law of causation in workers compensation to exclude an assessment that considered all of the impairment resulting from the accepted injury (ground 5 in the notice of appeal). 1. I propose to approach the issues on appeal by reference to these two substantive complaints. 2. A third issue was also the subject of oral submissions, namely whether it could be inferred that the Medical Assessor assessed permanent impairment without taking any account of any aggravation and exacerbation of Mr Wright's injury by reason of work-related issues after 5 December 2018. As this issue may influence the orders made on appeal, notwithstanding that this was not raised in the grounds of appeal, it is considered below. Legislative Scheme Statutory framework 1. The relevant legislative scheme for the purposes of this appeal includes the Compensation Act, the Management Act and the Workers Compensation Regulation 2016 (NSW) (the "2016 Regulation"). Under s 2A of the Compensation Act, the Compensation Act and the Management Act are to be construed together, with the Management Act prevailing in the event of any inconsistency. Injury giving rise to an entitlement to payment under the Compensation Act 1. Injury is defined in s 4(a) of the Compensation Act to mean "personal injury arising out of or in the course of employment", and in s 4(b) of the Compensation Act to include a "disease injury" which means: (i) a disease that is contracted by a worker in the course of employment but only if the employment was the main contributing factor to contracting the disease, and (ii) the aggravation, acceleration, exacerbation or deterioration in the course of employment of any disease, but only if the employment was the main contributing factor to the aggravation, acceleration, exacerbation or deterioration of the disease. 1. It is immediately apparent that the definition of injury incorporates a requirement that the injury arise out of or in the course of employment. All references to "injury" in the Compensation Act thus incorporate that requirement. 2. The centrality of this definition of "injury" is apparent from s 9 of the Compensation Act: (1) A worker who has received an injury (and, in the case of the death of the worker, his or her dependents) shall receive compensation from the worker's employer in accordance with this Act. (2) Compensation is payable whether the injury was received by the worker at or away from the worker's place of employment. 1. Section 9A(1) of the Compensation Act then imposes a specific causation requirement: No compensation is payable under this Act in respect of an injury (other than disease injury) unless the employment concerned was a substantial contributing factor to the injury. 1. Section 11A(1) of the Compensation Act provides: No compensation is payable under this Act in respect of an injury that is a psychological injury if the injury was wholly or predominantly caused by reasonable action taken or proposed to be taken by or on behalf of the employer with respect to transfer, demotion, promotion, performance appraisal, discipline, retrenchment or dismissal of workers or provision of employment benefits to workers. 1. Section 15(1) of the Compensation Act provides: (1) If an injury is a disease which is of such a nature as to be contracted by a gradual process— (a) the injury shall, for the purposes of this Act, be deemed to have happened— (i) at the time of the worker's death or incapacity, or (ii) if death or incapacity has not resulted from the injury—at the time the worker makes a claim for compensation with respect to the injury, and (b) compensation is payable by the employer who last employed the worker in employment to the nature of which the disease was due. Payments for injury under the Compensation Act 1. Section 33 of the Compensation Act provides for payment of weekly compensation where "total or partial incapacity for work results from an injury". 2. Section 60 of the Compensation Act provides that an employer is liable to pay for certain medical and other expenses where they are reasonably necessary "as a result of an injury received by a worker". 3. Section 65A(3) of the Compensation Act relevantly provides that no compensation is payable in respect of permanent impairment that results from a primary psychological injury unless the degree of permanent impairment resulting from the psychological injury is at least 15%. The note to s 65A(3) provides that "If more than one psychological injury arises out of the same incident, section 322 of the [Management Act] requires the injuries to be assessed together as one injury to determine the degree of permanent impairment." Disputes and assessments as to claims for compensation 1. Division 3 of Pt 4 of the Management Act sets out the process for the determination of disputes about workers compensation claims. Section 288 relevantly provides: 288 Referral of disputes to Commission (1) Any party to a dispute about a claim may refer the dispute to the President for determination by the Commission. However, if the dispute is about lump sum compensation, only the claimant can refer the dispute. Note— A medical dispute concerning the claim can also be referred for assessment under Part 7 (Medical assessment). (2) The President may not accept a dispute for referral for determination to the Commission if the dispute is a dispute that, under this Part, cannot be referred for determination by the Commission. 1. If a dispute is determined by the Commission, s 294 of the Management Act provides that the Commission must, as soon as practicable after the determination of the dispute, issue the parties to the dispute with a certificate as to the determination, attaching a brief statement setting out the Commission's reasons for the determination. 2. Part 7 of the Management Act provides a framework for the referral of medical disputes for medical assessment. Section 321(1) of the Management Act provides: A medical dispute (other than a dispute concerning permanent impairment of an injured worker) may be referred for assessment under this Part by a court, the Commission or the President, either of their own motion or at the request of a party to the dispute. The President is to give the parties notice of the referral. 1. "Medical dispute" is defined in s 319 of the Management Act as meaning a dispute between a claimant and the person on whom a claim is made about any of the following matters: the worker's condition: s 319(a), the worker's fitness for employment: s 319(b), the degree of permanent impairment of the worker as a result of an injury: s 319(c), whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality and the extent of that proportion: s 319(d), the nature and extent of loss of hearing suffered by a worker: s 319(e), whether impairment is permanent: s 319(f), and whether the degree of permanent impairment of the injured worker is fully ascertainable: s 319(g). As held in Skates v Hills Industries Ltd [2021] NSWCA 142 at [30] (Basten JA, Leeming JA agreeing) and [47] (Leeming JA), it is the medical dispute between the parties that is referred for assessment. The jurisdiction of the medical assessor is thus constrained by the ambit of the medical dispute referred for assessment: Scone Race Club Ltd v Cottom [2024] NSWCA 34 at [53] (Basten AJA, Gleeson and Mitchelmore JJA agreeing). 2. Section 321A of the Management Act concerns the referral of a medical dispute concerning permanent impairment. It relevantly provides: 321A Referral of medical dispute concerning permanent impairment (1) The regulations may make provision for or with respect to— (a) the circumstances in which a medical dispute concerning permanent impairment of an injured worker is authorised, required or not permitted to be referred for assessment under this Part, and (b) the giving of notice of a referral to the parties to the dispute. (2) Without limiting subsection (1), the regulations may provide that a medical dispute may not be referred for assessment under this Part if the dispute concerns permanent impairment of an injured worker where liability is in issue and has not been determined by the Commission. (3) A medical dispute concerning permanent impairment of an injured worker that is authorised or required by the regulations to be referred for assessment under this Part may be referred by a court, the Commission or the President, either of their own motion or at the request of a party to the dispute. 1. There are no regulations of relevance to the issues on appeal. 2. Section 322 of the Management Act relevantly provides: 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 Workers Compensation 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) A medical assessor may decline to make an assessment of the degree of permanent impairment of an injured worker until the medical assessor 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. 1. Section 325(1) of the Management Act provides that the medical assessor to whom a dispute is referred is to give a medical assessment certificate as to the matters referred for assessment. Section 325(2) of the Management Act sets out the form and contents of a medical assessment certificate as follows: (2) A medical assessment certificate is to be in a form approved by the President and is to— (a) set out details of the matters referred for assessment, and (b) certify as to the medical assessor's assessment with respect to those matters, and (c) set out the medical assessor's reasons for that assessment, and (d) set out the facts on which that assessment is based. 1. Section 327(1) of the Management Act provides that a party to a medical dispute may appeal against a medical assessment under Pt 7, but only in respect of a ground of appeal provided for under s 327(3) of the Management Act, which relevantly includes: (d) the medical assessment certificate contains a demonstrable error. 1. Section 328 of the Management Act sets out the procedure on appeal. Section 328(1) provides that an appeal against a medical assessment is to be heard by an appeal panel constituted by two medical assessors and one member of the Workers Compensation Division of the Commission. Section 328(2) provides that an appeal is to be by way of review of the original medical assessment, but the review is limited to the grounds of appeal on which the appeal is made. Pursuant to s 328(5) of the Management Act, the appeal panel may confirm the certificate of assessment or may revoke that certificate and issue a new certificate as to the matters concerned. Consideration Did the primary judge err as regards the construction of the Certificate of Determination? 1. The first of the substantive issues on appeal is whether the primary judge erred as to the proper construction of the Certificate of Determination, and thus as to the ambit of the estoppel. 2. The essence of Mr Wright's contention can be simply stated. He contends that, on their proper construction, orders 1 and 5 of the Certificate of Determination precluded Mr Wright contending that after 5 December 2018 he suffered aggravation and exacerbation of his psychological or psychiatric injury by reason of the claimed conduct of his employer and his perceptions thereof ("Post 5 December 2018 Work-related Issues") so as to constitute an injury within s 9(1) of the Compensation Act. However, it did not preclude Mr Wright from contending: 1. That after 5 December 2018, he suffered from aggravation and exacerbation of his injury by reason of Post 5 December 2018 Work-related Issues; and 2. That that aggravation and exacerbation resulted from, or was materially contributed to by, the psychological or psychiatric injury that he suffered in the period up to 5 December 2018 and thus could be taken into account in assessing the permanent impairment resulting from that injury. 1. Mr Wright contends that this necessarily flows from the following passage from the judgment of McColl JA (Giles and Campbell JJA agreeing) in Habib v Radio 2UE Sydney Pty Ltd [2009] NSWCA 231 at [186]: "Orders made by consent may create an estoppel as between parties, (and, no doubt may be considered for the purpose of determining whether subsequent proceedings would lead to conflicting judgments), however they do so "only as to those matters which are necessarily decided", to ascertain which "the court will closely examine all such evidence, if any, as is available and admissible, and, by the aid of such materials, will ascertain whether any and what adjudication of matters in dispute was expressed, or necessarily involved, in the actual decision assented to": Isaacs v Ocean Accident and Guarantee Corporation Ltd (1957) 58 SR (NSW) 69 (at 75), per Street CJ and Roper CJ in Eq; see generally the helpful discussion of the issue by Barrett J in Land Enviro Corp Pty Ltd v HTT Huntley Heritage Pty Ltd [2008] NSWSC 185; (2008) 72 NSWLR 160 (at [63] – [65]); Abigroup Contractors Pty Ltd (at [146])." 1. Mr Wright submits that the matter "necessarily decided" by the Certificate of Determination was whether the aggravation and exacerbation of his psychological or psychiatric injury as a result of Post 5 December 2018 Work-related Issues itself constituted injury for which compensation was payable under the Compensation Act. Mr Wright contends that the Certificate of Determination did not necessarily decide whether he suffered from an aggravation and exacerbation of his psychological or psychiatric injury by reason of Post 5 December 2018 Work-related Issues, nor did it necessarily decide whether any such aggravation and exacerbation itself resulted from, or was materially contributed to by, the 5 December 2018 Injury. 2. Thus, Mr Wright contends the primary judge erred in his Honour's conclusion as to the ambit of the estoppel arising from the Certificate of Determination. 3. In considering these contentions, the starting point is the language of the Certificate of Determination. The natural meaning of the language the parties used in orders 1 and 5 is that Mr Wright and the State agreed that Mr Wright was not entitled to payments under the Compensation Act in respect of his claimed aggravation and exacerbation of his psychological injury by reason of Post 5 December 2018 Work-related Issues. That flows from the clear terms of order 5, agreeing that there should be an award for the State in respect of the additional injury as alleged and specified in order 1. The "additional injury" alleged and specified in order 1 was a further aggravation and exacerbation of Mr Wright's psychological condition by reason of Post 5 December 2018 Work-related Issues. On their face, those two paragraphs indicate that Mr Wright and the State agreed that Mr Wright was not entitled to compensation under the Compensation Act in respect of the claimed aggravation and exacerbation of his psychological condition by reason of Post 5 December 2018 Work-related Issues. 4. That construction of the orders is supported by the ambit of the dispute between the parties which was resolved by the Certificate of Determination. As is apparent from consideration of ARD1 and Annexure A to the State's reply to ARD1, the dispute, at that time, was as to Mr Wright's entitlement to weekly compensation and payment of medical and related expenses under the Compensation Act in respect of his claimed injury or injuries, including as regards what fell within the description of what was alleged and specified as the "additional injury" (as set out at [11]-[12] above). Resolution of this dispute required an assessment of, or agreement as to, whether or not Mr Wright was entitled to compensation under the Compensation Act in respect of those matters. 5. As regards Mr Wright's claim for weekly compensation, that, in turn, directed attention to s 33 of the Compensation Act. The question under s 33 is as to whether total or partial incapacity for work "results from an injury" as defined in the Compensation Act. That test would be satisfied as regards the aggravation and exacerbation of his psychological injury, alleged and specified as the "additional injury" in order 1 of the Certificate of Determination, if the alleged incapacity for work was, as a matter of causation, incapacity that resulted from the 5 December 2018 Injury on the principles that Mr Wright relies upon on appeal derived from State Government Insurance Commission v Oakley (1990) 10 MVR 570; [1990] Aust Torts Reports 81-003 ("Oakley") and Secretary, New South Wales Department of Education v Johnson [2019] NSWCA 321 ("Johnson"). 6. Thus, the agreement as reflected in the Certificate of Determination as a whole, including the specific agreement as to weekly compensation in order 2, the agreement that there should be an award in favour of the State in respect of any allegation of incapacity beyond 7 November 2019 in order 3, the agreement in respect of medical and hospital expenses in order 4 and the agreement in order 5 that there should be an award for the State in respect of the "additional injury alleged and specified in Order 1", should be construed as reflecting agreement between the parties that Mr Wright could not claim under the Compensation Act in respect of the claimed aggravation and exacerbation of his psychological condition resulting from Post 5 December 2018 Work-related Issues. 7. I would thus reject Mr Wright's contention as to the proper construction of the Certificate of Determination, and of the estoppel arising therefrom. As the primary judge found (at [40]): "… The phrase ["additional injury"] was simply a shorthand term to identify a claim by the worker that "in the course of employment subsequent to 5 December 2018, as a result of [his] interactions with his supervisors, fellow employees and officers of the [employer] … he suffered further aggravation and exacerbation of a psychological condition." The effect of order 5 was to reject that claim." 1. Mr Wright's contention that the primary judge erred as to the proper construction of the Certificate of Determination should be rejected. It necessarily follows that the Appeal Panel erred in their construction of the Certificate of Determination, and of the ambit of the estoppel arising therefrom. 2. Grounds 1, 2 and 3 of the notice of appeal should be dismissed. Did the primary judge err in failing to apply the settled law of causation in workers compensation? 1. Mr Wright contends that the primary judge erred in finding that, by reason of the estoppel arising from the Certificate of Determination, the Medical Assessor was not entitled to have regard to aggravation and exacerbation of his psychological or psychiatric injury alleged to have been caused by Post 5 December 2018 Work-related Issues. Rather, Mr Wright contends, relying on well-established principles of causation deriving from Oakley and Johnson, that such aggravation and exacerbation can be taken into account in considering the extent of his impairment resulting from the 5 December 2018 Injury if the aggravation and exacerbation itself was caused, or contributed to, by that earlier injury. 2. Senior Counsel for Mr Wright submitted, during the hearing of the appeal, that his grounds of appeal relying upon causation could succeed even if his contention as to construction of the Certificate of Determination failed. 3. Ultimately, however, on what I have found to be the proper construction of the Certificate of Determination, it would not have been open to the Medical Assessor to find that any aggravation and exacerbation of Mr Wright's injury, resulting from Post 5 December 2018 Work-related Issues, was itself caused or contributed to by his 5 December 2018 Injury. That issue was resolved by orders 1 and 5 of the Certificate of Determination. Thus, principles of causation simply had no further work to do. 4. It necessarily follows that the Appeal Panel erred in finding that, irrespective of the breadth of the estoppel arising from the Certificate of Determination, the Medical Assessor would have been required to apply common law principles of causation to determine whether any aggravation and exacerbation of Mr Wright's psychological condition arising from Post 5 December 2018 Work-related Issues was caused or contributed to by the 5 December 2018 Injury. Having regard to the agreement reached in the Certificate of Determination, the issue whether that aggravation and exacerbation was caused or contributed to by the 5 December 2018 Injury was no longer in dispute between Mr Wright and the State. 5. Mr Wright's contention that the primary judge erred in this regard should thus be rejected. Grounds 4, 5 and 6 of the notice of appeal should be dismissed. Would it have been open to the Appeal Panel to infer that the Medical Assessor had rejected the possibility that Mr Wright's condition was aggravated and exacerbated by the conduct of the employer? 1. Notwithstanding my conclusions as set out above, it would have been open to the Medical Assessor to make an assessment of Mr Wright's permanent impairment having regard to aggravation and exacerbation of Mr Wright's injury after 5 December 2018 provided that he did not include in that assessment any aggravation and exacerbation which resulted from Post 5 December 2018 Work-related Issues. Had the Medical Assessor done so, there would be no demonstrable error in his decision. That may go to the relief that should be ordered, and whether declaration (2), as made by the primary judge, should be upheld, irrespective of the legal errors which I have found affected the analysis of the Appeal Panel. 2. As set out above, the Appeal Panel did not in fact address this issue. 3. The primary judge did address this issue and found (at [55]) that the Medical Assessor accepted Mr Wright's evidence that his psychological condition was aggravated by Post 5 December 2018 Work-related Issues (see above at [46]). Thus, his Honour found that it was not open to the Appeal Panel to find that the Medical Assessor had given effect to the estoppel arising from the Certificate of Determination: at [60]. 4. I have separately considered whether the Medical Assessor in fact excluded from consideration aggravation and exacerbation of Mr Wright's injury resulting from Post 5 December 2018 Work-related Issues. The following matters support the conclusion that he did not. 5. First, the Medical Assessor never suggested that he excluded such matters from his assessment. Rather, on the face of the Medical Assessment Certificate, he has approached his task as being to assess all impairment flowing from the 5 December 2018 Injury. Were it not for the Certificate of Determination, that would necessarily have been the correct approach for the Medical Assessor to take. 6. Second, it would not naturally be expected that a medical assessor would be alive to the principles going to construction of consent orders, and estoppel, which were ventilated before the Appeal Panel and the primary judge and which have been fully ventilated on appeal. Without some clear guidance as to such matters, it would not be expected that the Medical Assessor would have appreciated the parameters of his task having regard to the terms of the Certificate of Determination. 7. Third, the exchange of emails leading to agreement as to the deemed date of injury would not have alerted the Medical Assessor to the parameters of his task. Those emails focussed upon the date of injury, but did not identify the proper construction of the Certificate of Determination or the ambit of the estoppel arising therefrom. 8. Fourth, and most importantly, the Medical Assessment Certificate includes reference, in a number of places, to Mr Wright's Post 5 December 2018 Work-related Issues. The Medical Assessor identified, for example, that after Mr Wright's return to work in 2019 he "psychologically deteriorated" and that there were "further problems when he went back to work." The Medical Assessor also found that on account of ongoing harassment by Mr Wright's manager "eventually he had to stop work." These passages strongly suggest that the Medical Assessor assessed Mr Wright's permanent impairment including having regard to the impact that those Post 5 December 2018 Work-related Issues had on Mr Wright's psychiatric and psychological condition. 9. In these circumstances, I agree with the primary judge that the Medical Assessment Certificate contains a demonstrable error. The declaratory relief ordered by the primary judge is appropriate. Conclusion 1. It follows that this appeal must be dismissed. 2. Before the primary judge it was common ground that the appropriate relief, if the State's claim was successful, was to set aside the decision of the Appeal Panel and remit the matter to the President of the Commission for referral to an appeal panel differently constituted: at [5] and [59]. His Honour did not, however, make an order remitting the matter to the President of the Commission for referral to a differently constituted appeal panel. 3. In my judgment, in addition to the declaratory relief granted by the primary judge, an order should be made remitting the matter to the President of the Commission, either for referral of Mr Wright's claim of permanent impairment arising out of the 5 December 2018 Injury for further medical assessment under s 329 of the Management Act (see s 327(6) of the Management Act), or for referral of the State's appeal against the decision of the Medical Assessor to a differently constituted appeal panel for hearing under s 328 of the Management Act (noting that the powers of the Appeal Panel, in subs (5), are to confirm the certificate of assessment or revoke that certificate and issue a new certificate as to the degree of Mr Wright's permanent impairment resulting from the 5 December 2018 Injury). In the latter case, having regard to the terms of declaration (2) made by the primary judge, it would be incumbent upon any freshly constituted appeal panel to revoke the Medical Assessor's certificate and then to conduct its own assessment of Mr Wright's permanent impairment and reflect that assessment in a new certificate of assessment. 4. In both instances any further consideration of Mr Wright's claim should be made consistently with the reasons of the Court. 5. If no order as to remittal is made, as Senior Counsel for the State agreed during oral submissions, Mr Wright has not had his claim for permanent impairment assessed in the way in which it should be under the Management Act. 6. The State submitted that if it were successful in resisting Mr Wright's appeal there should be an order that each party bear its own costs. That order should be made. 7. Thus, the orders I propose are: 1. Leave to appeal is granted. 2. The appeal is dismissed. 3. In addition to the orders made by Basten AJ, the State of New South Wales' appeal against the decision of the Medical Assessor dated 16 August 2022 is remitted to the President of the Personal Injury Commission either: 1. For referral under s 329 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) ("Management Act") of Mr Wright's claim of permanent impairment arising out of his injury with a deemed date of 5 December 2018 for further medical assessment; or 2. For referral to a differently constituted appeal panel for hearing under s 328 of the Management Act of the State of New South Wales' appeal. 3. In either case, any further consideration of Mr Wright's claim should be made consistently with the reasons of the Court. 1. Each party is to bear its own costs of the appeal. ********** DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 11 April 2024