New South Wales Court of Appeal CITATION: STRASBURGER ENTERPRISES PTY LTD trading as QUIX FOOD STORES v SERNA [2008] NSWCA 354 HEARING DATE(S): 8 December 2008 JUDGMENT DATE: 18 December 2008 JUDGMENT OF: Basten JA at 1; Gyles AJA at 65; Hoeben J at 66 (1) Grant the appellant an extension of time within which to file its summons for leave to appeal up to and including 11 December 2007. (2) Grant the appellant leave to appeal against the decision in the District Court made on 28 August 2007 to extend the time within which Ms Serna could commence proceedings. DECISION: (3) Dismiss the appeal. (4) Order the appellant to pay the respondent's costs of the proceedings in this Court. CATCHWORDS: APPEALS – validity of administrative act required for purpose of civil proceedings – whether open to challenge in civil proceedings – collateral challenge to medical assessment certificate – Workplace Injury Management and Workers Compensation Act 1998 (NSW) s 327 - LIMITATION OF ACTIONS – extension of time – limitation period for work injury damages claim – whether prejudice to defendant precluded extension of limitation period – limits of court's discretion – Workers Compensation Act 1987 (NSW), s 151D - PRACTICE AND PROCEDURE – pre-filing statement – contents of pre-filing statement – objective test required to answer statutory description – whether failure to respond to pre-filing statement within prescribed time – Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 315(1), 316, 318 - WORKERS' COMPENSATION – medical assessment certificate – validity – whether holding valid medical certificate precondition to commencing work injury damages proceedings – validity of certificate showing two injuries not separately assessed – whether there can be one injury, resulting from two events – need for plaintiff to establish 15% permanent impairment – Workers Compensation Act 1987 (NSW), ss 4, 151H – Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 322, 323, 325, 327 – Safety, Rehabilitation and Compensation Act 1988 (Cth), ss 4(1), 5A - WORDS & PHRASES – "disease" – "impairment" – "injury" – "pre-filing statement" Anti-Discrimination Act 1977 (NSW), s 4 Safety, Rehabilitation and Compensation Act 1988 (Cth), ss 4, 5A LEGISLATION CITED: Supreme Court Act 1970 (NSW), s 75A Workers Compensation Act 1987 (NSW), ss 4, 15, 151, 151A, 151D, 151G, 151H Workmen's Compensation Act 1916 (NSW), s 5 Workplace Injury Management and Workers Compensation Act 1998 (NSW), ss 281, 313, 315, 316, 318, 322, 323, 325, 326, 327, 328, 350, 368; Ch 7, Pt 3, Div 4; Pt 6. Div 3 CATEGORY: Principal judgment Brisbane South Regional Health Authority v Taylor [1996] HCA 25; 186 CLR 541 Campbelltown City Council v Vegan [2006] NSWCA 284; 67 NSWLR 372 Canute v Comcare [2006] HCA 47; 226 CLR 535 Favelle Mort Ltd v Murray [1976] HCA 13; 133 CLR 580 JC Equipment Hire Pty Ltd v Registrar, Workers Compensation Commission (NSW) [2008] NSWCA 43; 5 DDCR 403 Itek Graphix Pty Ltd v Elliott [2002] NSWCA 104; 54 NSWLR 207 Leppington Pastoral Co Pty Ltd v Juweinat [2002] NSWCA 228 Madden v Kingston Industries Pty Ltd [2005] NSWCA 440 CASES CITED: Minister for Immigration and Multicultural Affairs v Bhardwaj [2002] HCA 11; 209 CLR 597 Ousley v The Queen [1997] HCA 49; 192 CLR 69 Rail Services Australia v Dimovski [2004] NSWCA 267; 1 DDCR 648 Salido v Nominal Defendant (1993) 32 NSWLR 524 The Salvation Army (South Australia Property Trust) v Rundle [2008] NSWCA 347 Tan v National Australia Bank Ltd [2008] NSWCA 198 Wattyl Australia Pty Ltd v McArthur [2008] NSWCA 326 Woolage v State of New South Wales [2001] NSWCA 256 Zickar v MGH Plastic Industries Pty Ltd [1996] HCA 31; 187 CLR 310 PARTIES: Strasburger Enterprises Pty Ltd trading as Quix Food Stores (Applicant) Kristy Ann Serna (Respondent) FILE NUMBER(S): CA 40863/07 COUNSEL: L King SC/T J Willis (Applicant) B G McManamey (Respondent) SOLICITORS: Sparke Helmore (Applicant) Stacks/Goudkamp (Respondent) LOWER COURT JURISDICTION: District Court LOWER COURT FILE NUMBER(S): DC 3890/07 LOWER COURT JUDICIAL OFFICER: District Court LOWER COURT DATE OF DECISION: 28 August 2007 IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 40863/07 DC 3890/07 BASTEN JA GYLES AJA HOEBEN J 18 December 2008 STRASBURGER ENTERPRISES PTY LTD T/as QUIX FOOD STORES v Kristy Ann SERNA Headnote Ms Serna ("the plaintiff") was employed by Strasburger Enterprises Pty Ltd ("the appellant") at a service station, with a small convenience store, in Edensor Park. In May and July 1999, the premises were robbed, as a result of which the plaintiff suffered distress amounting to a psychological injury. From shortly after the incidents until 23 December 2003, she received workers' compensation payments. In mid-January 2004, she sought legal advice. Thereafter, her solicitors made arrangements for her to see medical practitioners to ascertain whether she had suffered a 15% permanent impairment and thus satisfied the precondition to receipt of work injury damages, pursuant to s 151H of the Workers Compensation Act 1987 (NSW). Section 151D(2) of the Workers Compensation Act imposes a limitation period of three years with respect to a claim for work injury damages, the period running from "the date on which the injury was received". If the injury was received on the date of the second incident, the three year period would have expired on 1 July 2002. On 21 March 2006, the plaintiff sought leave from the District Court to commence proceedings out of time. On 28 August 2007, Hughes DCJ granted the plaintiff leave. On 15 July 2008, the appellant sought an extension of time to obtain leave to appeal. The Court granted the extension of time and leave to appeal. The issues for determination on appeal were: (i) whether the medical assessment certificate, relied on by the plaintiff, was valid; (ii) whether the appellant was precluded from defending proceedings on liability because it had failed to respond to a "pre-filing statement" within the time prescribed by s 316 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW); and (iii) whether, because of prejudice to the appellant, an extension of time to commence proceedings should have been granted. The Court held, dismissing the appeal (Basten JA, Gyles AJA and Hoeben J agreeing): In relation to (i) 1. The statutory scheme is consistent with both an injury and an impairment having multiple causes and an injury being the result of a course of conduct. No principle of general law or statutory provision suggests that a certificate identifying an injury resulting from more than one event or incident was, for that reason, invalid: [29]. Canute v Comcare [2006] HCA 47; 226 CLR 535; Favelle Mort Ltd v Murray [1976] HCA 13; 133 CLR 580; Zickar v MGH Plastic Industries Pty Ltd [1996] HCA 31; 187 CLR 310; Leppington Pastoral Co Pty Ltd v Juweinat [2002] NSWCA 228; Madden v Kingston Industries Pty Ltd [2005] NSWCA 440; Woolage v State of New South Wales [2001] NSWCA 256, considered. Rail Services Australia v Dimovski [2004] NSWCA 267; 1 DDCR 648 , referred to. 2. It is not necessary to determine whether it was open to a District Court judge to reject the certificate as legally invalid because the basis for such rejection has not been made out. At the very least, for the purposes of an application for extension of time, it has not been demonstrated that the plaintiff did not have a reasonably arguable case that she satisfied the statutory precondition with respect to the degree of permanent impairment: [34]. Minister for Immigration and Multicultural Affairs v Bhardwaj [2002] HCA 11; 209 CLR 597; Ousley v The Queen [1997] HCA 49; 192 CLR 69; Campbelltown City Council v Vegan [2006] NSWCA 284; 67 NSWLR 372, referred to. In relation to (ii) 3. The inflexible statutory timetable imposed on a prospective defendant requires that the defendant must be able to identify with a degree of confidence the date on which a pre-filing statement has been served upon it, under s 315(1) of the Workplace Injury Management Act. In the pre-filing statement, the plaintiff must include a statement and the evidence on which he or she seeks to rely: [44]. 4. A letter of 10 February 2006 neither annexed nor identified material which might have constituted evidence on which the plaintiff sought to rely. Despite a statement in the letter to the contrary, it did not constitute a pre-filing statement. A letter of 31 March 2006 clearly satisfied the requirements of a pre-filing statement, enclosing the particulars of the claim, copies of various medical reports and other documents intended to be relied upon: [44]–[45]. 5. The appellant responded to the pre-filing statement within 42 days of being served with the second letter; therefore, the appellant is not precluded by s 318(1)(c) from defending on the question of liability: [47]. In relation to (iii) 6. With respect to s 151D(2) and similar provisions, which contain no express indication of the matters to be considered in relation to an application to extend time, the limits of the court's discretion are to be found in the subject matter, scope and purpose of the statute: [52]. Brisbane South Regional Health Authority v Taylor [1996] HCA 25; 186 CLR 541; Itek Graphix Pty Ltd v Elliott [2002] NSWCA 104; 54 NSWLR 207 ; Salido v Nominal Defendant (1993) 32 NSWLR 524; The Salvation Army (South Australia Property Trust) v Rundle [2008] NSWCA 347, considered. 7. The totality of the evidence of prejudice relied upon by the appellant did not demonstrate any significant level of actual prejudice caused by the delay. There was no attempt made to relate the evidence to the particulars of negligence. Despite the somewhat elliptical nature of the trial judge's reasons, the appellant has not demonstrated that the trial judge's decision – that the complaint of actual prejudice had not been made out – was erroneous: [59], [63]. IN THE SUPREME COURT OF NEW SOUTH WALES COURT OF APPEAL CA 40863/07 DC 3890/07 BASTEN JA GYLES AJA HOEBEN J 18 December 2008 STRASBURGER ENTERPRISES PTY LTD T/as QUIX FOOD STORES v Kristy Ann SERNA Judgment 1 BASTEN JA: In May and July 1999 Ms Serna ("the plaintiff") was employed by Strasburger Enterprises Pty Ltd ("the appellant") at premises at Edensor Park in western Sydney. She operated the cash register at the premises which constituted a service station with a small convenience store. On two occasions, in May and July 1999 respectively, the premises were robbed, as a result of which the plaintiff suffered distress amounting to a psychological injury. From shortly after the incidents until 23 December 2003 she received workers' compensation payments. When those payments were terminated, she sought legal advice. 2 According to an affidavit filed in the District Court, she first received advice that she may be entitled to claim work injury damages in mid-January 2004. Thereafter, her solicitors made various arrangements for her to see medical practitioners, in order to ascertain whether she had suffered a 15% permanent impairment and thus satisfied the precondition to receipt of work injury damages, pursuant to s 151H of the Workers Compensation Act 1987 (NSW). 3 The Workers Compensation Act imposes a limitation period of three years with respect to a claim for work injury damages, the period running from "the date on which the injury was received": s 151D(2). If the injury was received on the date of the second incident, the three year period would have expired on 1 July 2002. The plaintiff required leave to commence proceedings in the District Court out of time. This she sought by notice of motion served on 21 March 2006. After a number of adjournments, the motion was heard by Hughes DCJ, who delivered judgment granting the plaintiff leave on 28 August 2007. 4 The application for leave to appeal against his Honour's order first came before this Court on 15 July 2008. That application (somewhat ironically) was out of time. The matter was not ready to proceed on 15 July, the appellant having sought on the same day to adduce further evidence, such evidence being relevant not merely to an extension of time within which to seek leave to appeal, but also to the substantive issue as to whether the plaintiff should have been given leave to institute proceedings. 5 When the matter came back before the Court on 8 December 2008, further evidence had been filed. Although the explanation given by the solicitor for the appellant in relation to the delay in seeking leave to appeal was less than satisfactory, it was not apparent that any prejudice had been caused to the plaintiff and she did not seek to be heard in opposition to the extension of time. That extension should be granted. 6 The plaintiff did not seek to cross-examine any person with respect to the further evidence adduced in support of the proposed appeal, but she did object to the tender of that material. Although tendered under cover of a solicitor's affidavit, the material was almost entirely a collection of letters, reports and other documents created in the course of the proceedings. Much of it was not adverted to in the course of oral argument. No index of the material was provided to the Court, but it appears that some of it was before the trial judge in any event. 7 The hearing below having been concerned with an interlocutory application to commence proceedings, there was some doubt as to the application of s 75A(8) of the Supreme Court Act 1970 (NSW). However, because of the issues to which it related, which will be addressed below, it is convenient to allow all of the material in as evidence on the hearing of the appeal. 8 The appellant identified three issues as arising for the Court's determination. They were: (a) a challenge to the validity of the medical assessment certificate relied on by the plaintiff; (b) a challenge to the finding that the appellant was precluded from defending the proceedings on liability, because it had failed to respond to a "pre-filing statement" within the time prescribed by s 316 of the Workplace Injury Management and Workers Compensation Act 1998 (NSW) ("the Workplace Injury Act "), and (c) a challenge to the discretionary judgment that, given the likely prejudice to the appellant, it was appropriate to grant the plaintiff an extension of time to commence proceedings. 9 These issues, and the material relevant to each, will be addressed in turn. Each of the matters gives rise to an issue of importance in the circumstances of the case and accordingly it is appropriate to grant leave to appeal. Nevertheless, for the reasons set out below, the appeal should be dismissed. 10 In addition to the issues raised above, the appellant complained that the reasons of the trial judge were inadequate. It is not necessary to address that complaint. There was no oral testimony before the trial judge and nothing about the issues raised gave his Honour any advantage over this Court in determining the proper outcome. The appeal being by way of rehearing, it is accordingly appropriate for this Court to address the substantive issues relied upon by the appellant. Validity of medical assessment certificate 11 A personal injury which arises out of or in the course of employment may be the subject of a claim for compensation (a statutory claim) or a claim for damages under the general law (or both). A claim for general law damages is subject to the substantive limitations imposed by Part 5 of the Workers Compensation Act. It is also subject to the procedural limitations to be found in Ch 7 of the Workplace Injury Act, in particular, Part 3, Div 4 of that Chapter. 12 The nature of the requirements have changed significantly over the years, but it was common ground in the present proceedings that the relevant provisions were those contained in the current Act which have been in force in substantially identical terms since 1 January 2002. Their operation, in various respects, has been summarised in decisions of this Court, including, recently, Tan v National Australia Bank Ltd [2008] NSWCA 198 at [31]-[45] and [86]-[95] (Young CJ in Eq) and Wattyl Australia Pty Ltd v McArthur [2008] NSWCA 326 at [5]-[49] (Beazley JA). Their operation in specific circumstances has raised questions about which different views have been expressed: see, eg, JC Equipment Hire Pty Ltd v Registrar, Workers Compensation Commission (NSW) [2008] NSWCA 43; 5 DDCR 403 at [39]-[40] (Tobias JA, Campbell and Bell JJA agreeing) in relation to the construction of s 326 and the operation of a medical assessment certificate; cf Wattyl Australia at [59] (Beazley JA). It is appropriate to confine the consideration of the statutory scheme to those issues requiring determination for the disposal of these proceedings. 13 The Workers Compensation Act provides that no damages may be awarded unless the injury results in a degree of permanent impairment of the injured worker that is at least 15%: s 151H(1). As the note to the section indicates, the procedure for assessing the degree of permanent impairment is prescribed by s 322 of the Workplace Injury Act: see also s 151H(4). However some procedural requirements are also to be found in s 151H(2) and (3), to which reference will be made shortly. The holding of a valid medical assessment certificate is not necessarily a precondition to commencement of work injury damages proceedings, but in the case of a medical dispute, absent a certificate other preconditions to the commencement of proceedings cannot be satisfied: Workplace Injury Act, s 313. Accordingly, if the certificate were invalid it was arguable that the relevant preconditions had not yet been satisfied. Further, the validity of the certificate was relevant for the plaintiff to demonstrate an arguable case that damages were recoverable in order to obtain an extension of time. 14 On 30 January 2005, the plaintiff obtained an assessment from Mr Sam Borenstein, a clinical psychologist, indicating a degree of impairment of 25%. The appellant's insurer did not accept that assessment and, on 7 April 2005, the plaintiff filed in the Workers Compensation Commission an application to resolve a dispute. 15 On 21 September 2005 an approved medical specialist, Dr Newman Harris, identified the degree of permanent impairment as 15%. In his certificate, he identified the date of injury as both 29 May and 2 July 1999. He assessed no proportion as due to a pre-existing injury and ascribed the whole of the 15% to "this injury". It is clear that Dr Harris treated her degree of impairment as resulting from one indivisible injury. 16 A medical assessment certificate is conclusively presumed to be correct as to the degree of permanent impairment of the worker "as a result of an injury": s 326(1)(a). It is, however, subject to correction and appeal. If the Registrar of the Commission is satisfied that a certificate contains "an obvious error" the Registrar may issue or approve the specialist issuing a replacement certificate: s 325(3). That did not happen here. Further, a party to the medical dispute may appeal against the medical assessment, but only on the grounds identified in s 327(3). Those grounds include the assessment having been made "on the basis of incorrect criteria" and to the certificate containing "a demonstrable error": s 327(3)(c) and (d). If such a complaint is made, it is to be made within 28 days of the assessment, unless the Registrar grants an extension of that period: s 327(5). No appeal was lodged with respect to the certificate in the present case. 17 The appellant now seeks to contend that leave should not have been granted to extend the time within which to commence proceedings because the certificate was either invalid or demonstrated on its face that there were two injuries, neither of which, assessed separately, could have reached 15% of permanent impairment, since they only reached that statutory floor in combination. For this purpose, the appellant relied upon a medical report dated 16 March 2004, provided by the plaintiff's treating psychiatrist, Dr S K Law, estimating that "the first robbery contributed to 40% of her mental distress, and the 2nd robbery contributed to 60% of her mental distress". (Dr Law did not assess the degree of permanent impairment.) 18 The appellant submitted that there were two separate incidents giving rise to separate causes of action and injuries. The circumstances were properly analysed in accordance with the approach adopted by this Court in Woolage v State of New South Wales [2001] NSWCA 256. Woolage had a degree of similarity on its facts, the plaintiff in that case having been injured in two separate but almost identical incidents, when a desk chair mounted on casters moved under him and he landed on his coccyx on the floor. 19 It is true that in Woolage the Court (and the parties) approached the application of s 151G, as it was prior to 1 January 2002, on the basis that an assessment was required with respect to each injury. However, the plaintiff had pleaded his case by reference to separate causes of action with respect to each injury, an approach which both the parties and the Court accepted as available. In following that course, the Court said nothing about whether an alternative approach might validly have been adopted. 20 An alternative approach is illustrated by the decision in Leppington Pastoral Co Pty Ltd v Juweinat [2002] NSWCA 228. In that case the plaintiff had been injured as a result of three separate incidents involving lifting of heavy articles: at [3]. The negligence, which covered all three incidents, was a failure to institute proper work systems: at [7]. The appellant sought to rely upon Woolage for the proposition that if there were three incidents, there were necessarily three causes of action and damages should have been assessed separately in respect of each: at [11]. However, as Davies AJA (with whom Stein JA and Foster AJA agreed) explained, the plaintiff "was entitled to claim as the injury for which he sought compensation the condition which resulted from the three incidents in the appellant's employment": at [23]. It was not a case in which damages for separate injuries were sought in reliance upon separate causes of action: at [27]. This Court accepted in Madden v Kingston Industries Pty Ltd [2005] NSWCA 440 at [30] that there is no inconsistency between Woolage and Leppington. It is a matter for the plaintiff to identify the injury with respect to which he or she claims damages and, in due course, to establish the relevant causal connection between that and any negligence on the part of the employer accepting, no doubt, that allowance may need to be made in the course of assessing damages for the effects of any pre-existing condition, for which the employer was not responsible. 21 In the present case the appellant challenged that approach, submitting that under the Workers Compensation Act, an injury was to be identified by reference to a particular incident. At least for the purposes of s 151H, an employee could not accumulate the consequences of separate incidents so as to satisfy the statutory floor, below which a claim must fail. 22 If this analysis is to operate, it must do so in some circumstances but not others. For example, there will undoubtedly be injuries, falling within the definition of "injury" in s 4 of the Workers Compensation Act, which do not arise from a specific incident or event. The term "injury" includes a "disease" which, as is recognised by s 15, may be contracted by a gradual process. Other forms of personal injury, which may or may not constitute a disease, may result from exposure to work conditions over time. The elements of the definition, at least in pars (a) and (b), are not exclusive of each other: see Favelle Mort Ltd v Murray [1976] HCA 13; 133 CLR 580 at 588-589 (Barwick CJ); Zickar v MGH Plastic Industries Pty Ltd [1996] HCA 31; 187 CLR 310 at 329-330 (Toohey, McHugh and Gummow JJ). All that is required is that the injury arise out of or in the course of employment, or, in the case of a disease, be contracted in the course of employment. The contention that the injury must be connected with a specific incident or event harks back to the long since repealed requirement of the Workmen's Compensation Act 1916 (NSW) which referred to "personal injury by accident" arising out of and in the course of employment: s 5(1), discussed by Kirby J in Zickar at 339. 23 The Safety, Rehabilitation and Compensation Act 1988 (Cth) includes a definition of "injury" in s 5A, which is similar to that contained in s 4 of the Workers Compensation Act, but not identical and differently structured. In considering that definition, in Canute v Comcare [2006] HCA 47; 226 CLR 535, the High Court stated at [10]: "First, the Act does not oblige Comcare to pay compensation in respect of an employee's impairment; it is liable to pay compensation in respect of 'the injury'. Secondly, the term 'injury' is not used in the Act in the sense of 'workplace accident'. The definition of 'injury' is expressed in terms of the resultant effect of an incident or ailment upon the employee's body. Thirdly, the term 'injury' is not used in a global sense to describe the general condition of the employee following an incident." 24 The Workers Compensation Act is expressly stated not to affect "any liability in respect of an injury to a worker that exists independently of this Act, except to the extent that this Act otherwise expressly provides": s 151. That for which the worker sues is a liability of the defendant under the general law in respect of "an injury". The result will be an award of damages recovered "in respect of an injury": s 151A(1). The threshold requirement, as already noted, is identified by reference to a degree of permanent impairment of the injured worker. The impairment results "from an injury" and, in accordance with s 151H, is to be assessed in the following manner: " 151H No damages unless permanent impairment of at least 15% (1) No damages may be awarded unless the injury results in the death of the worker or in a degree of permanent impairment of the injured worker that is at least 15%. … (2) In assessing whether the 15% threshold has been met (that is, whether the degree of permanent impairment resulting from an injury is at least 15%): (a) impairment resulting from physical injury is to be assessed separately from impairment resulting from psychological injury, and … (c) the 15% threshold is not met unless the degree of permanent impairment resulting from physical injury is at least 15% or the degree of permanent impairment resulting from psychological injury is at least 15%." 25 This provision differentiates between physical and psychological injury and requires that the degree of impairment resulting from each be separately assessed. 26 It follows from this structure that there can be more than one injury resulting from one event: the question posed by the appellant is whether there can be one injury resulting from two events, at least where the injury is psychological and not physical. 27 "Impairment" is also a state or condition that may result from more than one injury or may itself contain multiple forms, as appears from ss 322 and 323 of the Workplace Injury Act, which provide: " 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 …. (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. … 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 … 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 … 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." 28 Impairment is not defined in the Workers Compensation Act or the Workplace Injury Act. It is defined in the Safety, Rehabilitation and Compensation Act 1988 (Cth), s 4(1) to mean "the loss, the loss of the use, or the damage or malfunction, of any part of the body or of any bodily system or function or part of such system or function". The same concept, in more elaborate form, is reflected in the definition of "disability" in the Anti-Discrimination Act 1977 (NSW), s 4(1). 29 This statutory scheme is consistent with both an injury and an impairment having multiple causes and an injury being the result of a course of conduct. Where, either under the general law or pursuant to the statute, it is necessary to apportion liability or responsibility for a particular injury, that will be done, in the absence of contrary statutory prescription, according to general law principles: see, eg, Rail Services Australia v Dimovski [2004] NSWCA 267; 1 DDCR 648 at [35] (Handley JA). There is no principle of general law or statutory provision which would suggest that a certificate identifying an injury resulting from more than one event or incident was, for that reason, invalid. The certificate might be subject to appeal or review because the reasons given by the assessor demonstrate legal error or, possibly, factual error. However, no such claim is supportable in the present circumstances. 30 There is a further question as to whether it was open to the appellant to raise a complaint about the certificate in the present circumstances. Where an issue may be raised in the course of proceedings as to the validity of an administrative act, a collateral challenge to the validity of the act may be considered, apparently on the basis of circumstances which may constitute jurisdictional error in administrative law, or possibly for error disclosed on the face of the document: see Ousley v The Queen [1997] HCA 49; 192 CLR 69 at 85 (Toohey J), 87 (Gaudron J), 102 (McHugh J), 127 (Gummow J) and 146 (Kirby J). A particular statutory scheme may indicate that such review is unavailable: see Minister for Immigration and Multicultural Affairs v Bhardwaj [2002] HCA 11; 209 CLR 597 at [8] (Gleeson CJ) in relation to the power of a tribunal to reconsider its own earlier decision; see also at [129] (Kirby J dissenting). 31 It is arguable that the Workplace Injury Act provides a statutory scheme which is inconsistent with a right of collateral challenge in civil proceedings in the District Court. Thus, an appeal is provided against a medical assessment "but only in respect of a matter that is appealable under this section and only on the grounds for appeal under this section": s 327(1). The appeal is to be made by application to the Registrar and is "not to proceed" unless the Registrar is satisfied that at least one of the grounds "has been made out": s 327(4). The grounds include the assessment being made on the basis of "incorrect criteria" and the certificate containing "a demonstrable error": s 327(3)(c) and (d). For a party to rely, in civil proceedings for damages, on legal error of a kind which would almost certainly fall within the available grounds of appeal under s 327 would be to bypass the procedural constraints imposed by s 327. Further, where an appeal is heard, it is conducted by two medical specialists and an arbitrator, not by a judicial officer: s 328. 32 On the other hand, it may be thought that the statutory scheme of appeal does not allow for proper consideration of legal error. Further, although decisions of the Commission are subject to a privative clause (s 350) approved medical specialists are not members of the Commission (see s 368) and their decisions may not be protected from judicial review. 33 A second question which arises in this context is whether a decision of an approved medical specialist is an administrative decision for the purposes of principles relating to collateral review. This Court has held that the function exercised by a medical assessor attracts the duty to give reasons: see Campbelltown City Council v Vegan [2006] NSWCA 284; 67 NSWLR 372. 34 It is not necessary to determine for the purposes of the present appeal whether it was open to a District Court judge to reject the certificate as legally invalid, because the basis for such rejection has not been made out. At the very least, for the purposes of an application for extension of time, it has not been demonstrated that the plaintiff did not have a reasonably arguable case that she satisfied the statutory precondition with respect to the degree of permanent impairment. Accordingly, the ground of appeal must be rejected. Failure to file response to pre-filing statement 35 The second matter raised by the appellant requires some further reference to the statutory preconditions for making a claim for work injury damages and the particular procedural steps taken in the present case. 36 The procedural steps required are set out in Ch 7 of the Workplace Injury Act. The chapter relates to claims both for compensation and for work injury damages. The provisions relevant for present purposes are found in Part 6 of Ch 7. (It may be that the relevant date is the date when the particular procedural steps occurred, which was early 2006, but nothing was suggested to turn on that for the purpose of identifying the relevant statutory provisions.) Part 6, Div 3 relates to pre-filing statements and relevantly provides: " 315 Requirement for pre-filing statement before commencing court proceedings (1) Before a claimant can commence court proceedings for the recovery of work injury damages, the claimant must serve on the defendant a pre-filing statement setting out such particulars of the claim and the evidence that the claimant will rely on to establish or in support of the claim as the Rules may require. … 316 Defendant must respond to pre-filing statement (1) The defendant must, within 28 days after the pre-filing statement has been served on the defendant, respond to the pre-filing statement by: (a) accepting or denying liability (wholly or in part), and (b) (to the extent, if any, that the defendant does not accept liability) serving on the claimant a defence to the claim setting out such particulars of the defence and evidence that the defendant will rely on to defend the claim as the Rules may require. … (2) If the defendant fails to respond to the pre-filing statement as required by this section within 42 days after it is served on the defendant, the claimant can commence court proceedings for the recovery of work injury damages. … 318 Parties limited to pre-filing statement and defence (1) For the purposes of court proceedings on a claim for work injury damages: (a) the claimant is not entitled to file a statement of claim that is materially different from the proposed statement of claim that formed part of the pre-filing statement served by the claimant, except with leave of the court, and (b) the defendant is not entitled to file a defence that is materially different from any defence served on the claimant in response to the claimant's pre-filing statement within 42 days after service of the pre-filing statement, except with leave of the court, and (c) the defendant is not entitled to file a defence that wholly or partly disputes liability for the claim if the defendant has failed to serve on the claimant a defence to the claim as required by this Division within 42 days after the claimant served the pre-filing statement on the defendant, and (d) a party to the proceedings is not entitled to have any report or other evidence admitted in the proceedings on the party's behalf if the report or other evidence was not disclosed by the party in a pre-filing statement or defence served under this Division, except with leave of the court." 37 This scheme involves potential traps and strategic decisions for both parties. First, a prospective plaintiff is required to have not only particulars of his or her claim prepared, but also all the evidence on which it is proposed to rely if the matter comes to court, before serving a pre-filing statement. Subject to one possible qualification noted below, later changes to the particulars or additions to the evidence can only be made with leave of the court, which will not be granted unless the court is satisfied that the material concerned was "not reasonably available" when the pre-filing statement was served and the failure to grant leave would substantially prejudice the plaintiff's case: s 318(2). 38 On one view, the strategic difficulties faced by a defendant are greater. It does not control the time at which a prospective plaintiff may serve a pre-filing statement, but whenever that happens, failure to give particulars of its proposed defence within 42 days will preclude it disputing liability, without the possibility of any indulgence granted by the court: s 318(1)(c). 39 The precision envisaged by the statutory scheme may not be reflected in steps actually taken prior to proceedings. In the present case, the critical question was identifying the date on which the plaintiff had served her pre-filing statement. The appellant's response, including a defence to the claim, was not served until 20 April 2006. The appellant would therefore not be entitled to defend on liability, unless the pre-filing statement had been served after 9 March. The plaintiff said that the statement had been served on 10 February 2006. The 42 day period would then have expired on 24 March. 40 It is not in doubt that, on 10 February 2006, the solicitors for the plaintiff wrote to both the appellant and the appellant's workers' compensation insurer noting that a claim for work injury damages had been made on 29 November 2005 and that the time for determining the claim under that provision had expired on 29 January 2006. The letter continued: "Accordingly we enclose by way of service our client's pre-filing statement in accordance with s 315(2)(c) of the Workplace Injury Management and Workers Compensation Act 1998." 41 The letter was accompanied by a draft statement of claim which set out the "particulars of the claim" sufficiently to satisfy s 315(1). (The reference to s 315(2)(c) related to a separate precondition to serving a pre-filing statement, namely the failure to determine the claim under s 281.) 42 However, the letter was accompanied by no material which could be said to constitute "evidence" proposed to be relied on in support of the claim. In its terms, it did not comply with the definition of a "pre-filing statement" contained in s 315(1), unless, for some reason, the plaintiff did not intend at that time to rely upon any evidence. The plaintiff did not suggest that was the case; rather, she said that all the material or evidence available to her had already been supplied to the appellant. To the extent that she might obtain further evidence, she acknowledged that she would not be able to rely on such material without leave of the Court. 43 The appellant in effect accepted the plaintiff's submission that it was not necessary to file all the material at once, for the purposes of s 315(1). However, the appellant argued that the Court could look to statements served later by the plaintiff as demonstrating that the pre-filing statement had not been served in its entirety on the earlier date. In particular, the appellant referred to a second letter of 31 March 2006 which enclosed "by way of service" not only the statement already served on 10 February, but five medical reports and the medical assessment certificate (which all pre-dated 10 February 2006), together with an expert report on "liability" dated 26 February 2006. 44 The inflexible statutory timetable imposed on a prospective defendant requires that the defendant must be able to identify with a degree of confidence the date on which a pre-filing statement has been served upon it. An express statement by the plaintiff's solicitor that a document constitutes a pre-filing statement will carry significant weight, but will not be decisive. If it is clear that the document so identified does not, by itself, comply with the statutory requirements for a pre-filing statement and was not intended to do so, that may provide a sufficient indication to the contrary. The fact that reports and other material which might be relied upon by the plaintiff in proposed proceedings had already been provided to a defendant may make it unnecessary to serve further copies of those documents. Whether or not that is so need not be determined in the present case: there is an available argument that the requirement for service would only be satisfied by giving a document in circumstances where the relevant statutory purpose is expressly identified at the time at which it is provided. On the other hand, s 315(1) does not expressly require service of, say, medical reports, but only service of a statement "setting out … the evidence". That question need not be decided because, as a minimum requirement, the plaintiff must identify the evidence on which she seeks to rely, which is to be treated as part of the pre-filing statement. It is not for the defendant to determine which documents in its possession the plaintiff relies upon for that purpose. The letter of 10 February 2006 neither annexed nor identified material which might constitute evidence on which the plaintiff sought to rely. Accordingly, despite the statement in the letter to the contrary, it did not constitute a pre-filing statement. 45 The letter of 31 March 2006 clearly did satisfy the requirements of a pre-filing statement. It enclosed the particulars of the claim and copies of the various medical reports and other documents which were intended to be relied upon. It also included the letters of 10 February, though the reason for serving them was not clear. 46 As the appellant noted, the plaintiff also served a copy of a new report with respect to liability, with the letter of 31 March 2006. It argued that, even if a pre-filing statement had been served on 10 February, the provision of a further report, prior to the service of a response by the defendant, and within the period for serving such a response, should be treated as "completing" the earlier pre-filing statement, with the result that the 42 day period would recommence. 47 While, from a strategic perspective, that contention may in some circumstances have attractions for either or both parties, it is less clear whether the statutory scheme envisages a process whereby the fixed period can start and then recommence. Because, on the evidence, the relevant pre-filing statement was not served until 31 March 2006 and the appellant's response was served within 42 days of that event, it is clear that the appellant is not precluded by s 318(1)(c) from defending on the question of liability: other issues should be left for resolution in circumstances where that is necessary. 48 Before concluding that the appellant is entitled to succeed on this argument, it is necessary to note the plaintiff's contention that the appellant should not be entitled to raise the argument at all. The plaintiff relies on the fact that, when the plaintiff asserted at the hearing on the motion to extend time in the District Court that the appellant was precluded from defending with respect to its liability, counsel for the appellant conceded the point. 49 That contention gave rise to a dispute about the circumstances of the concession, whether the lawyers for the appellant had been taken by surprise by the argument and whether the plaintiff's lawyers had conducted themselves on an inconsistent basis prior to the hearing of the motion. 50 The plaintiff's contention should be rejected. As explained above, the letter of 10 February 2006, together with the annexure, did not constitute a pre-filing statement for the purposes of s 315. That conclusion has been reached on the basis of that material alone. That material was before the primary judge. The failure of the appellant to take the position it took in this Court might, if that had been the only issue, have resulted in a refusal of leave to appeal. However, as it was not the only issue to be addressed, there is no reason to refuse leave to appeal on that ground. There was no question of there being other evidence which the plaintiff might have called in the District Court which would have been relevant to this issue. (The failure of the appellant to take the point could have consequences in respect of the costs of the hearing in the District Court, if the appellant were to succeed in setting aside the order made below.) Prejudice to the appellant through the extension of time 51 The limitation period with which the plaintiff had not complied was to be found in s 151D of the Workers Compensation Act which, so far as relevant, provided: " 151D Time limit for commencement of court proceedings against employer for damages … (2) A person to whom compensation is payable under this Act is not entitled to commence court proceedings for damages in respect of the injury concerned against the employer liable to pay that compensation more than 3 years after the date on which the injury was received, except with the leave of the court in which the proceedings are to be taken. (3) The Limitation Act 1969 does not apply to or in respect of court proceedings to which this section applies." 52 With respect to this and similar provisions, which contain no express indication of the matters to be considered in relation to an application to extend time, "the limits of the discretion are to be found in the subject matter, and the scope and purpose, of the statute": Salido v Nominal Defendant (1993) 32 NSWLR 524 at 530F (Gleeson CJ); see also 535-539 (Kirby P) and 541 (Powell JA). Subsequently, the High Court provided guidance as to the correct approach in Brisbane South Regional Health Authority v Taylor [1996] HCA 25; 186 CLR 541, although the majority judgments did not speak in identical language and were concerned with a limitation provision which provided some guidance as to factors to be taken into account. As explained in The Salvation Army (South Australia Property Trust) v Rundle [2008] NSWCA 347 at [96] by McColl JA: " Brisbane South is authority for the proposition that an application for an extension of time under limitation legislation should be refused if the effect of granting the extension would result in significant prejudice to the potential defendant … 'Significant prejudice' means such prejudice as would make the chances of a fair trial unlikely … . For a trial to be fair, it need not be perfect or ideal … ." 53 In relation to s 151D(2), the relevant principles were discussed in Itek Graphix Pty Ltd v Elliott [2002] NSWCA 104; 54 NSWLR 207, by Ipp AJA with whom Spigelman CJ and Sheller JA agreed. Sheller JA, after referring to the fact that actual significant prejudice might compel a refusal by the court to extend time, added that "it is not correct to conclude that the absence of such prejudice compels an exercise of discretion in favour of the plaintiff": at [3]. Itek itself was concerned with a particular additional consideration, namely that the prospective plaintiff had quite deliberately decided, on an informed basis, not to proceed within the specified period. 54 In the present case, the appellant complained that, although the plaintiff asserted that she had not received advice from her previous solicitors (who acted in both her compensation claim and a claim for criminal injuries compensation), there was no evidence from those solicitors as to why no steps had been taken to pursue a claim for work injury damages. 55 If there were any suggestion that the plaintiff had discussed the matter with her former solicitors or that there had been an attempt by them to assess the degree of permanent impairment she had suffered or an attempt to identify her prospects in succeeding on liability, the complaint would have had some force. However, none of these matters was raised with her (indeed she was not cross-examined) and it would not be appropriate to infer that any decision was taken, whether informed or otherwise, in respect of such a claim. 56 As to the circumstances in which the incidents occurred, it is common ground that CCTV footage is available and will provide some objective evidence of the circumstances of the robberies. (It appears that neither party had viewed the CCTV footage prior to the hearing, each placing responsibility on the other for that omission.) There were, in addition, statements taken by the police in respect of the incidents. On each occasion, police attended at the service station. 57 An employee of the appellant, Ms Tina Robinson, swore an affidavit on 17 April 2007 in which she said that she had identified the store manager (Mr Prasad) and the area manager (Mr Walsh) at the time of the incidents, stated that they had both left the employment of the company (Mr Prasad prior to March 2000 and Mr Walsh in or about March 2001) and that she was unaware of their whereabouts. She gave no evidence of any inquiries made as to their whereabouts. She also stated: "The Edensor Park Mobil Quix Store has undergone numerous changes in layout since the alleged date of injury. I am not aware of the layout of the store at the time of injury. As far as I am aware, there are no employees currently employed by the Defendant who would have this knowledge." 58 Ms Robinson was not cross-examined. What was meant by her reference to the "layout" of the store, and what inferences might be drawn with respect to the particulars of negligence as pleaded, remain obscure. 59 It may be seen that the totality of the evidence of prejudice relied upon by the appellant was sparse. More importantly, there was no attempt made to relate the evidence to the particulars of negligence. Despite the concession that the response to the pre-filing statement was out of time, the trial judge appears to have had regard to issues relevant to liability. Although his reasons were somewhat elliptical, the trial judge was not satisfied that a complaint of actual prejudice had been made out by the appellant. 60 As noted above, the plaintiff obtained a report from a Mr Richard Jennings, who described himself as a "licensed security consultant, certified risk manager and certified workplace assessor and trainer". He gave his experience as including 12 years as a detective at New Scotland Yard and 10 years as a director of an Australian investigation and security company. He identified means available in 1999 to provide an appropriate level of security and protection in respect of a 24 hour operation where only one employee was rostered on during the night shift. Although, no doubt, his evidence might be challenged at trial, he had sufficient information available to him to describe the security systems which were in operation at the time of the two robberies. He noted that after the first robbery "an automatic door locking system was installed whereby the Plaintiff could lock the entry doors by pressing a button at the console, preventing a person from entering". He also recorded the plaintiff's evidence as to the absence of training in any aspect of security or safety. She said she was told by a manager that if she were confronted by a robber, she should "give them whatever they wanted". Mr Jennings expressed an opinion as to the additional protective devices which should have been installed, with, no doubt, appropriate training in their use. 61 With respect to the events of the evenings in question, it seems unlikely that there was any material available from employees of the appellant in 1999 which would have been relevant to challenge any evidence the plaintiff or the police might have given. There was no suggestion that the appellant's managers took statements from any person or that they otherwise had information as to the circumstances of the robberies. So far as the security measures installed in the store in May and July 1999 were concerned, it may be inferred that both the store manager and the area manager would have had some familiarity with the measures taken and with any training given to the operators in respect of those devices. However, the store manager had apparently left his employment within 10 months of the second incident and the area manager had left within two years. Because there was no evidence as to what steps had been taken to locate them in 2006, it follows that there was no evidence as to the whether such steps would have been more likely to succeed in 2002. (In fact, it must have been apparent to the appellant by early 2005 that a work injury damages claim was being considered.) This, however, remains the high point of the appellant's case on prejudice. 62 In relation to what devices and training were available in 1999 and what might reasonably have been expected to be installed at that time, it seems unlikely that any evidence has been lost as a result of the delay in commencing proceedings. In any event, no evidential basis for drawing such an inference was provided. 63 In my view, taken at its highest, the evidence did not demonstrate any significant level of actual prejudice caused by the delay. Accordingly, despite the elliptical nature of his Honour's reasons, the appellant has not demonstrated that his Honour's decision was erroneous, according to the principles identified in House v The King which have been held to be applicable to the resolution of such questions: see Rundle at [95] and [134]. Conclusions 64 For the reasons indicated above, I would propose the following orders: (1) Grant the appellant an extension of time within which to file its summons for leave to appeal up to and including 11 December 2007. (2) Grant the appellant leave to appeal against the decision in the District Court made on 28 August 2007 to extend the time within which Ms Serna could commence proceedings. (3) Dismiss the appeal. (4) Order the appellant to pay the respondent's costs of the proceedings in this Court. 65 GYLES AJA: I agree with Basten JA. 66 HOEBEN J: I agree with Basten JA and the orders he proposes. ********** 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.