CHALMERS v ACCIDENT COMPENSATION CORPORATION [2023] NZHC 925

CHALMERS v ACCIDENT COMPENSATION CORPORATION [2023] NZHC 925 [26 April 2023]IN THE HIGH COURT OF NEW ZEALANDAUCKLAND REGISTRYI TE KŌTI MATUA O AOTEAROATĀMAKI MAKAURAU ROHECIV-2022-404-1535[2023] NZHC 925UNDER the Accident Compensation Act 2001IN THE MATTER of a special leave application pursuant tos 162 of the ActBETWEEN DALE CHALMERSApplicantAND ACCIDENT COMPENSATIONCORPORATIONRespondentHearing: 22 February 2023Appearances: B Hinchcliff for the ApplicantF Becroft for the RespondentJudgment: 26 April 2023JUDGMENT OF HARVEY JThis judgment was delivered by me on 26 April 2023 at 4.30 pmpursuant to r 11.5 of the High Court Rules.Date: ..(Deputy) RegistrarSolicitors:ACC and Employment Law, AucklandMedico Law Limited, AucklandIntroduction[1] In 2000, Dale Chalmers (then aged 38) was diagnosed with multiple sclerosis(MS). As her condition advanced and her health deteriorated, Ms Chalmers' medicalteam including her orthopaedic specialist, Edward Yee, confirmed that she neededsurgery. Otherwise, a spinal condition that had developed could deteriorate and leadto her becoming a paraplegic. Ms Chalmers underwent spinal surgery on 7 February2018. Soon after she suffered a T6 paraplegia injury. On 12 February, Mr Yee filedan ACC claim for a treatment injury as the outcome was "unexpected and devastating".[2] On 2 May 2018, the Accident Compensation Corporation declined cover. Thepresent proceedings stem from that and subsequent related decisions. An appeal to theDistrict Court was filed on 6 January 2021. Judge D L Henare dismissedMs Chalmers' appeal on 5 May 2022.1 She subsequently sought leave to appeal tothis Court. That application was also dismissed by Judge P R Spiller on16 August 2022.2 Ms Chalmers now applies for special leave to this Court.[3] The issue for determination is whether leave should be granted.Background[4] It is accepted that Ms Chalmers has pre-existing multiple sclerosis. She tookan MRI scan on 16 November 2017 which revealed a large thoracic disc protrusion atT6/73 and severe spinal canal narrowing in the same area.4 Dr Pereira, a neurologist,recorded in a referral letter the next day, in part, that Ms Chalmers should proceed withsurgery because she "believe[d] it is contributing to [Ms Chalmers'] immobility". Shereferred Ms Chalmers for a surgical opinion.[5] Then on 17 December 2017, Dr Yee, an orthopaedic surgeon, recorded in hiscorrespondence with Dr Pereira that Ms Chalmers wanted to proceed with surgery. Henoted that he had informed Ms Chalmers that it was not possible to determine whetherher spine injury as described above or her pre-existing MS were causing her1 Chalmers v Accident Compensation Corporation [2022] NZACC 79.2 Chalmers v Accident Compensation Corporation [2022] NZACC 156.3 Between the sixth and seventh thoracic vertebrae.4 Spinal canal narrowing can cause compression on the spinal cord.symptoms, including "extreme difficulty walking". He also informed Ms Chalmersof the potential risks and side effects of the surgery including that "thoracic discremovals are associated with a high risk of spinal cord injuries and thus paraplegia".He also confirmed that where a disc is calcified it will often be completely adherentto the dura (membrane surrounding the spinal cord) and a dural tear is very likely as aresult of attempting to remove it.[6] The surgery took place on 7 February 2018. It went well howeverMs Chalmers did suffer a dural tear which had to be patched.5 On 8 February 2018,the on-duty doctor noted Ms Chalmers appeared not to have voluntary motor powerin her lower body. Dr Yee recorded that "[u]nfortunately the clinical picture today issuggestive of post-operative paraplegia which is one of my major concerns from theoperation". An MRI found oedema (swelling) within the spinal cord at the T6/7 levelbut no obvious physical issues contributing to lack of lower body motion. Thediagnosis of post-operative paraplegia was confirmed on 9 February 2018.Ms Chalmers also suffered neurological deterioration which is linked with theparaplegia.[7] Five days after the surgery, Dr Yee lodged a claim for cover with theCorporation. He stated in a supporting letter to the technical claims manager that theparaplegia was "unexpected and devastating". In subsequent correspondence, Dr Yeeexplained that it was difficult to identify what was specifically responsible for theparaplegia, but there was "no doubt" that the surgery was responsible.[8] The Corporation then obtained an independent opinion dated 5 April 2018 fromDr Pai based on a desktop review. This report recorded Dr Pai's opinion thatparaplegia following surgery "is a rare surgical complication". In a review of theliterature, he recorded that neurological issues occur at a risk of 20 per cent for thissurgery. The Corporation then decided on 2 May 2018 to decline cover, claiming thatthe paraplegia was an ordinary consequence of the treatment and that that the newsymptoms Ms Chalmers was experiencing were from progression of her underlyingspinal cord impairment and multiple sclerosis.5 This did not contribute to the paraplegia.[9] Following that, on 24 May 2018, Dr Pereira reported a post-operativeparaplegia neurogenic bladder and bowel dysfunction. She also referred topost-operative MRI imaging which showed at the T6/7 level a localised, enhancingsignal change which "do not look typical of an MS lesion".[10] On 17 November 2019 in a supplementary report, Dr Pai stated that based onresearch the incidence of Ms Chalmers' injury is 4 to 10 per cent. A summary ofstudies was provided. This was then raised to 20 per cent considering the pre-existingmultiple sclerosis, but no reasons were provided.[11] On 27 October 2020 Dr Noventa made a report reviewing the clinical notesand other existing documents relating to the claim. She concluded that "whileacknowledging paraplegia was a possible outcome it was likely not an expectedoutcome".Procedural history[12] After the initial decision to decline cover, a late review application was filed inApril 2019 which was not accepted by the Corporation.6 A subsequent review upheldthat decision. Following that, there was an appeal which was resolved by the partiesagreeing to have the issue remitted back to review.7 That took place on 8 December2020, and on 5 January 2021 the review was dismissed.[13] On 5 May 2022 Judge Henare delivered her decision on the appeal.8 The Judgeset out the agreed facts and medical evidence.9 She recorded the agreement betweenparties that there was a casual nexus between the surgery and the post-surgeryparaplegia. The "only issue to resolve" was:10whether or not the post-surgical paraplegia is an ordinary consequence of thetreatment, taking into account all of the circumstances of the treatment,6 A previous review application had been filed and withdrawn by another advocate. The Aprilapplication stated that the legal fees of the first advocate were prohibitive and withdrawal wasdone without Ms Chalmers' consent.7 Chalmers v Accident Compensation Corporation DC Auckland ACR 310/19, 20 April 2020(Minute of Judge JH Walker).8 Chalmers v Accident Compensation Corporation, above n 1.9 At [5]–[44].10 At [47].including Ms Chalmers' underlying health condition and the clinicalknowledge at the time of the treatment.[14] After canvassing the parties' submissions Judge Henare set out the legalframework in some detail. She referred to s 32 of the Accident Compensation Act2001 (the ACC Act) which defines "treatment injury" as excluding "an ordinaryconsequence of the treatment".11 Judge Henare stated the leading case on "not anordinary consequence" was the Court of Appeal decision Accident CompensationCorporation v Ng and cited the Court's analysis.12 The Court of Appeal held thephrase means "an outcome that is outside the normal range of outcomes, somethingout of the ordinary which occasions a measure of surprise". Judge Henare highlightedthe Court of Appeal's point that the test had moved away from statistical frequencyalone to tests which permit the decision maker to exercise judgment.13[15] Judge Henare noted that in the period prior to surgery Ms Chalmers' mobilitywas rapidly declining. Ms Chalmers knew that if she did not have surgery, hercondition would most likely lead to paraplegia.14 She also knew that paraplegia wasa risk of the surgery itself. The surgery was challenging but went smoothly. AlthoughDr Yee had stated in his application to the Corporation that the outcome was"unexpected and devastating" this had to be assessed in light of his clinical reportsboth pre- and post-surgery where paraplegia was an acknowledged risk.15 While theparaplegia was neither expected nor desirable it was not "surprising".16[16] Further, while accepting statistics could not be determinative, Judge Henareconsidered they were a relevant consideration and took account of Dr Pai's statisticalevidence. She did, however, note that she preferred his estimate of a 4–10 per centrisk because that was supported by a study provided in evidence, whereas for hisestimate of 20 per cent risk in Ms Chalmers' case he did not identify the basis for thisclaim.1711 At [58].12 At [59]–[60], citing Accident Compensation Corporation v Ng [2020] NZCA 274, [2020] 2 NZLR683 at [67]–[72].13 At [61].14 At [69]–[72].15 At [77].16 At [77].17 At [84]–[85].[17] The Judge then summarised her findings accordingly:18(a) The nature of the harm suffered is paraplegia. It is a severe condition thatwill prevent Ms Chalmers from walking for the rest of her life.(b) Ms Chalmers' multiple sclerosis may have made her more susceptible topost-operative paraplegia since, in the view of Dr Pereira, it wascontributing to her immobility.(c) Mr Pai's (sic) analysis of medical statistics indicates there is in general a 4to 10% chance of post-operative paraplegia after the type of surgeryundertaken by Ms Chalmers.(d) Mr Yee (sic) indicated before the operation was performed there was a highrisk of post-operative paraplegia.[18] Judge Henare concluded that while Ms Chalmers' paraplegia was devastating,her post-operative paraplegia was within the normal range of consequences of thesurgical treatment, and thus an ordinary consequence of the surgery.19 The appeal wasdismissed.[19] On 16 August 2022 Judge Spiller considered the leave to appeal application.20Ms Chalmers' advocate argued that multiple sclerosis is an irrelevant considerationbecause the evidence establishes the surgery caused the paraplegia; the Courtincorrectly relied on Dr Pai's evidence who is not a neurosurgeon and his percentageswere incorrect; and the Court incorrectly found that a four to 10 per cent chance ofinjury does not occasion a measure of surprise whereas in Accident CompensationCorporation v Ng the Court of Appeal found that Ms Ng's 16–22 per cent and Ms L's10–38 per cent chances occasioned a measure of surprise.[20] Judge Spiller found that Judge Henare's decision contained no errors of lawand turned to assess whether any errors of fact amounting to an error of law werepresent.21 First, the Judge found that Judge Henare did not make a mistake of fact inher reference to multiple sclerosis because it made her more susceptible to the adverse18 At [87].19 At [88].20 Chalmers v Accident Compensation Corporation, above n 2.21 At [37].consequence of paraplegia.22 Secondly, the Judge found that Judge Henare wasentitled to refer in support to the opinion of Dr Pai and his statistical analysis.23Thirdly, the Judge found that Judge Henare did not make a mistake of fact in findingthat Ms Chalmers' chance of an injury did not occasion a measure of surprise becausethis is a matter of judgment for the decision-maker and Judge Henare was entitled tomake the finding she did on the available evidence.24[21] Judge Spiller accordingly held that Ms Chalmers has not established sufficientgrounds, as a matter of law, to sustain her application for leave to appeal. Even if thequalifying criteria had been made out, the Judge would not have exercised discretionto grant leave because he was not satisfied as to the wider importance of any contendedpoint of law.25Applicant's submissions[22] Mr Hinchcliff raised two grounds upon which leave is sought. First, hesubmitted that the District Court failed to undertake an appropriate analysis of themeaning of "ordinary consequence" per s 32(1)(c) of the ACC Act and correctly applythe Court of Appeal decision in Accident Compensation Corporation v Ng.26Secondly, he contended the District Court was in error because the evidence isinconsistent with and contradictory to the decision; the only reasonable conclusion onthe evidence contradicts the decision. Accordingly, counsel submitted that theproposed appeal was on an error of law as set out in the authorities summarised in YZv Accident Compensation Corporation.27[23] Counsel referred to the Court of Appeal decision Accident Compensation v Ngwhere "not an ordinary consequence" was defined as something out of the ordinarywhich occasions a measure of surprise.28 The respondents in that decision, accordingto Mr Hinchcliff, were granted cover for their injuries noting that the risk for Ms Ng's22 At [38].23 At [39].24 At [40].25 At [41].26 Accident Compensation Corporation v Ng, above n 12.27 YZ v Accident Compensation Corporation [2020] NZACC 160.28 Accident Compensation Corporation v Ng above n 12.injury was between 16 and 22 per cent and for Ms L's injury ranged between 10 to 38per cent.[24] In particular Mr Hinchcliff contended that the District Court judgment is inerror for three reasons. First, the Court found the word "unexpected" does not meansurprising. Counsel pointed to the evidence of Dr Yee where he stated the outcomewas unexpected. Mr Hinchcliff contended that unexpected means not expected orregarded as likely to happen, which is synonymous with not ordinary per s 32(1) ofthe Act.[25] Secondly, the Court was in error, according to Mr Hinchcliff, by finding a 4–10 per cent chance of post-operative paraplegia does not create an element of surprise,and by doing so it wrongly expanded the definition of s 32(1). Counsel referred to theappellants' risk of injury in Ng and noted those risks were much higher thanMs Chalmers'. He submitted that the conclusion that the paraplegia was within theordinary range of consequences appeared to be based on the prior knowledge thatparaplegia was the biggest risk of surgery. However, the judgment also recognised, asdid the Court of Appeal in Ng, that the focus must be on the outcome that occurred noton the outcome predicted in advance of treatment.29[26] Additionally in Ng the Court recognised, in Mr Hinchcliff's submission, thatthe duration and severity is relevant. Further Mr Hinchcliff suggested that the researchquoted in Dr Pai's opinion indicated that the chance of paraplegia was less than 1.2per cent. Overall, on this argument counsel submitted that the District Courtmisapplied s 32 and Ng creating a serious argument that the facts were incorrectlyapplied to the law, in that a 4–10 per cent risk of an event occurring is not ordinaryand creates an element of surprise.[27] Thirdly, Mr Hinchcliff submitted the Court was in error by finding paraplegiawas within the normal range of consequences of the surgical treatment. He referredto the above submissions and added that a key piece of evidence, that of Dr Pai statingthe outcome was a "rare surgical complication", was omitted from the judgment.29 At [71].Respondent's submissions[28] Ms Becroft submitted that the District Court had applied the correct testconsistent with the principal authorities. The District Court exercised its ownjudgment in concluding the outcome was an ordinary consequence of surgery. TheCourt acknowledged the stark choices faced by the appellant which were made knownto her. While the consequences were devastating, they were not unexpected orsurprising, according to the District Court decision.[29] In addition, Ms Becroft argued that it is difficult to detect any error of law inthe District Court judgment, given its careful consideration of the tests and theauthorities. Moreover, counsel submitted that the questions raised by the appellantturn on the District Court's factual findings. More importantly, according toMs Becroft, an applicant must show an error of law which is a high threshold andrequires the Court to conclude that the judgment was so clearly untenable that a correctapplication of the law required a different answer. Accordingly, the Corporationcontended that the judgment was not untenable because the evidence demonstratedthat the outcome was not unexpected or surprising but was instead a known andsignificant risk. That risk was taken in light of the applicant's serious and deterioratingcondition.[30] According to Ms Becroft, the applicant contended that the District Court madeerrors in finding that: the word "unexpected" does not mean surprising; a 4 to 10 percent chance of post-operative paraplegia does not create an element of surprise; andthe post-operative paraplegia was within the normal range of consequences of thetreatment.[31] Expanding on the first point, Ms Becroft argued that the applicant hadsuggested the evidence from Dr Yee describing the outcome of paraplegia asunexpected and devastating meant that the Court could not conclude that paraplegiawas an ordinary consequence of the surgery. In response she highlighted the followingpoints made by the District Court.30 First, counsel for the applicant had overstated theposition and that the outcome was not surprising. Dr Yee had told the applicant that30 Chalmers v Accident Compensation Corporation, above n 1, at [72], [78] and [79].there was a high risk of paraplegia, so his statements need to be read within that contextalong with his clinical reporting, having regard to the applicant's underlying health.While paraplegia was devastating and not the outcome desired, that was the extent towhich it was unexpected – that it was not a desired outcome. The District Courtaccordingly gave little weight to Mr Yee's description of the outcome as unexpectedin assessing whether the paraplegia occasioned surprise.[32] Secondly, Ms Noventa, the physiotherapist, used comparable language toDr Yee. Even so, reference to the Court of Appeal discussion in Ng in her report wasincomplete with no reference being made to an ordinary consequence being within thenormal range of outcomes or the requirement that the applicant's underlying health beconsidered. In addition, the analogy made by Ms Noventa to car accidents, accordingto the District Court, demonstrated she did not properly understand the test forordinary consequence.[33] Counsel contended that all of the evidence needs to be considered andultimately the question of whether an outcome is surprising is a determined on thefacts. Counsel argued that Judge Henare carefully explained the elements relevant toher decision emphasising the stark choices the applicant faced; the advice given to herregarding risks and the significant risk of paraplegia; the applicant's own evidence thatshe understood her position pre-surgery and the risks associated with it; and the factthat the surgeons were not surprised by the post-surgery outcome. Accordingly,Ms Becroft argued that the District Court's assessment of the evidence does notamount to any error of law. Judge Henare correctly applied the law to the factsreaching a conclusion that was available.[34] On the issue of statistics, counsel submitted that the District Court concludedthese were relevant considerations, alongside the numerous other relevant factors setout at [87] of the judgment. Counsel contended that what the applicant proposes isprecisely what the Court of Appeal in Ng warned against. Rather than relying overlyon statistics alone as to ordinary consequence, the District Court took a more nuancedapproach.[35] Ms Becroft submitted that the applicant's suggestion the District Court ignoredDr Pai's description of paraplegia following surgery as a "rare" surgical complicationtakes that reference out of context. Dr Pai's statement does not negate a finding of anordinary consequence since his views cannot be minimised to a single sentence. It isone part of the evidential puzzle, according to counsel. Contrary to the applicant'sassertions, Judge Henare carefully considered Dr Pai's reports along with the availableevidence to reach the conclusion that the outcome was an ordinary consequence.Ms Becroft contended that this conclusion was available because:(a) the surgery was high risk and offered in light of the applicant's rapidlydiminishing mobility;(b) the applicant was told of and understood the risks of surgery including the highrisk of paraplegia;(c) paraplegia was unexpected but that does not mean the outcome was not anordinary consequence;(d) while the outcome was clearly devastating, no one was surprised by it,including the applicant.[36] In summary, Ms Becroft submitted that the applicant has not made out aseriously arguable question of law. The District Court's approach was consistent withthat of the Court of Appeal in Ng. In short, counsel argued that the applicant has notestablished that the District Court decision was so clearly untenable that a properapplication of law required a different answer. Accordingly, Ms Becroft submittedthat the application for leave should be declined.Legal principles and framework[37] Section 162 of the ACC Act provides:162 Appeal to High Court on question of law(1) A party to an appeal who is dissatisfied with the decision of theDistrict Court as being wrong in law may, with the leave of the DistrictCourt, appeal to the High Court.(2) The leave of the District Court must be sought within 21 days afterthe District Court's decision.(3) If the District Court refuses to grant leave, the High Court may grantspecial leave to appeal.(4) The special leave of the High Court must be sought within 21 daysafter the District Court refused leave.(5) The High Court Rules 2016 and sections 126 to 130 of the DistrictCourt Act 2016, with all necessary modifications, apply to an appealunder this section as if it were an appeal under section 124 of that Act.[38] An appeal may be made to the High Court only on a question of law. The Courtwill not grant leave for appeal on the basis of an error of fact "dressed up" as an errorof law.31 However, a mixed question of law and fact is matter of law.32 Additionally,the decision-maker's treatment of facts may amount to an error of law where there isno evidence to support the decision, the evidence is inconsistent with andcontradictory of the decision, or the true and only reasonable conclusion on theevidence contradicts the conclusion.33 Whether a statutory provision has beencorrectly interpreted and applied to the facts is a question of law.34[39] The point of law must be capable of bona fide and serious argument.35 Leaveis not to be granted as a matter of course.36 On second appeal the appeal court'sfunction is not to generally correct error but to clarify the law and determine whetherit has been properly interpreted and applied by the lower Court.37 The primary focusis on whether the question of law is worthy of consideration.38 In Keyon v AccidentCompensation Corporation this Court emphasised that the proposed appeal should bedeserving of scarce judicial time, have an issue of principle at stake, and have areasonable prospect of success.39 Where leave has been refused by the District Court31 Northland Co-operative Dairy Co Ltd v Rapana [1999] 1 ERNZ 361 (CA) at 363.32 Commissioner of Inland Revenue v Walker [1963] NZLR 339 at 354.33 Edwards v Bairstow [1995] 3 All ER 48.34 Commissioner of Inland Revenue v Walker, above n 32, and Edwards v Bairstow, above n 33.35 Impact Manufacturing Ltd v Accident Rehabilitation and Compensation Insurance CorporationHC Wellington AP266/00, 6 July 2001.36 Gilmore v Accident Compensation Corporation [2016] NZHC 159437 Tohu v Accident Compensation Corporation HC Auckland CIV-2003-404-4869, 12 November2003 at [13].38 Cullen v Accident Compensation Corporation [2014] NZCA 94 citing Khan v AccidentCompensation Corp HC Auckland CIV-2007-485-1632, 14 August 2008 at [5] and DownerConstruction (New Zealand) Ltd v Silverfield Developments Ltd [2007] NZCA 355, [2008] 2NZLR 591 at [33].39 Kenyon v Accident Compensation Corporation [2002] NZAR 385.there will normally have to be some extraordinary factor which has not been properlytaken into account to justify leave.40[40] The desirability of finality of litigation is a relevant consideration, as is theoverall interest of justice.41Discussion[41] I consider that there is a bona fide and serious argument that, with great respectto the learned Judge, she erred in the interpretation of "not an ordinary consequenceof the treatment" and its application to paraplegia resulting from spinal surgery of aperson with an existing spinal disease. Whether a statutory provision has beenproperly construed, interpreted and applied to the facts is a question of law. So too iswhere there is a mixed question of fact and law, which is virtually inevitable in theassessment of cases under s 32 in light of the Court of Appeal's comments that"s 32(1)(c) requires an analysis that is rooted in the facts of the particular case".42[42] Again with respect to the Judge, I consider there is a serious argument that shewas in error by finding that the fact doctors and Ms Chalmers were well aware of therisk and possibility of paraplegia means there could not have been a "measure ofsurprise". Such a conclusion at first blush seems overly broad in light of advancedmedical technology, knowledge and understanding that can predict a wide variety ofrisks, and doctors' obligations to inform their patients of such risks. The Court ofAppeal in Ng stated that "the focus should be on whether the outcome that occurred iswithin the range of ordinary consequences rather than whether the risk of the outcomewas predicted in advance of treatment in a particular claimant's case".43 There is valuein clarifying the legal position for whether (and when) adverse consequences whichare predictable and indeed predicted may still "occasion a measure of surprise" for thepurposes of being a treatment injury.40 At [15].41 Cullen v Accident Compensation Corporation, above n 38.42 McEnteer v Accident Compensation Corporation [2010] NZCA 126, [2010] NZAR 301.43 At [71].[43] Additionally, the Judge appears to have taken into account the factMs Chalmers may have inevitably been facing paraplegia due to her multiplesclerosis.44 In particular, in her summary of the relevant circumstances, the Judgestated "Ms Chalmers' multiple sclerosis may have made her more susceptible to post-operative paraplegia since it was contributing to her immobility in the view of DrPereira".45 It is arguable an error of law may have arisen here, given the findings ofthe High Court in Ng (findings which were not upset on appeal):46[94] Mr Butler also submitted that, in assessing the ordinary consequence oftreatment, the Court was also entitled to have regard to what the consequencesof the underlying health condition, if left untreated, would be. However, suchan argument loses sight of the fact that what s 32(1)(c) is addressing is theordinary consequence of the treatment, not the ordinary consequence (oroutcome) of the medical condition. If a particular medical condition, leftuntreated, would likely result in death, but death was an extremely unlikelyand unpredictable outcome of the medical treatment, then it is not possible tosay that, notwithstanding the extreme rarity of the treatment having causedthat outcome, there was no cover because it would eventually have happenedanyway if there had been no treatment at all.[95] There is no doubt that the failure of a treatment to achieve the desiredcure does not, of itself, amount to "treatment injury". That is somethingdifferent from where the treatment, wholly unexpectedly, produces a similaradverse outcome to that which would ultimately have occurred as a result ofthe underlying medical condition. Indeed, the words "of itself" in s 32(3)indicate that a failure to achieve the desired result, coupled with other factors,may potentially amount to a treatment injury.[96] Mr Butler submitted:To provide cover in situations where a patient has had surgery in orderto prevent an outcome, and that outcome occurs anyway, would treatwhat is a result of a disease as being an injury.[97] That submission is incorrect. If the treatment has itself unexpectedlyproduced the adverse outcome, it is the treatment and not the underlyingcondition that is the proximate cause of the outcome. In assessing whether anoutcome is a reasonable consequence of the treatment, the probability that asimilar outcome might have occurred anyway is irrelevant.[44] Although the meaning of "not an ordinary consequence" was considered bythe Court of Appeal in Ng, I nonetheless find that the question of law proposed forappeal in this case is worthy of consideration. Court of Appeal recognised in Ng that44 Chalmers v Accident Compensation Corporation, above n 1, at [19], [20], [23], [69], [72], [86]and [87(b)].45 At [87(b)].46 Accident Compensation Corporation v Ng [2018] NZHC 2848.its interpretation "does not provide the precision or comprehensive guidance thatcounsel were seeking".47 The meaning of s 32 will develop as a matter of lawthrough its application to various types of factual applications, the present being oneof them. There are distinctive features that interact with the legal test, and if thatinteraction were clarified it would provide precedent value. Namely, the fact MsChalmers has an underlying condition which would have led to paraplegia if untreated;the knowledge the risk of paraplegia was possible before the surgery; and the fact thatthe paraplegia is a permanent and very severe consequence. There is thus an issue ofprinciple at stake.[45] For completeness I do not accept Mr Hinchcliff's submission that the claimantsin Ng, Ms Ng and L, received cover from the Court of Appeal with statistical risk ofadverse consequence from treatment being much higher than that of Ms Chalmers.The Court of Appeal did not grant cover to the claimants. Their claims were remittedto the District Court for reconsideration. Counsel did not provide me with thedecision(s) on the reconsidered claims and I do not know the outcome.Decision[46] Leave to appeal is granted on the approved question: Did the District Court failto correctly apply s 32(1)(c) of the Accident Compensation Act 2001?_____________________________Harvey J47 Accident Compensation Corporation v Ng, above n 12 at [72].