"Smashed" by mosquitoes at Yamba
51 Ms Farrow-Smith's case faced two problems, one specific and one general.
(a) The specific problem was that, according to Dr Hannah's notes, she reported to him that she had been "smashed" by mosquitoes while she was at Yamba (which was in early March 2020). If that happened, it was a potential source of infection - unrelated to Ms Farrow-Smith's employment - whose timing aligned fairly closely with what (according to Professor Korman and Dr Navin) was to be inferred from the serology reports. Unless mosquito bites at Yamba could be excluded (or shown to be no more than speculation), it would be extremely difficult for the Tribunal to be persuaded that the ailment suffered by Ms Farrow-Smith was "contributed to, to a significant degree, by [her] employment".
(b) The more general problem was that it was uncontroversial that RRV was endemic in the Northern Rivers region. Ms Farrow-Smith gave evidence of the precautions taken to minimise mosquito activity in her house and garden (and that she did not recall being bitten at home), but she could not realistically exclude (and on my reading did not try to exclude) the possibility of having been bitten by a mosquito in February or March 2020 in circumstances not connected with her employment.
52 As to the specific problem, the Tribunal clearly regarded Dr Hannah's notes of the consultation on 9 April 2020 as a faithful record of what Ms Farrow-Smith said to him on that occasion: that is, Ms Farrow-Smith told Dr Hannah that she had been "smashed" by mosquitoes at Yamba.
53 Ms Farrow-Smith was taken to Dr Hannah's notes of 6 and 9 April in cross-examination, largely in an attempt to establish that she had not complained on those occasions of being continuously unwell since 28 February. The issue of mosquitoes at Yamba was touched on briefly, as follows.
Did you tell him - sort of the next line - 'Was down in Yamba and got smashed by mosquitoes?'---No. I told him - he said where have you been, and I said that I've been - told him where I'd been, but I didn't say that I was in Yamba and got smashed by mosquitoes. That doesn't follow.
54 It was thus put to Ms Farrow-Smith that she had said words to the effect of what was recorded in Dr Hannah's notes. However, the important issue was not the contents of her conversation with Dr Hannah but whether, in fact, she had sustained a significant number of mosquito bites at Yamba. Although it does not clearly state a finding in these terms, the emphasis on Dr Hannah's notes is hard to explain unless such a finding was being made implicitly. The Tribunal must be taken to have found at least a significant likelihood that Ms Farrow-Smith was bitten during her time at Yamba (so that infection in March was a more persuasive explanation for the serology results than infection in February combined with a delayed immune response).
55 The proposition that Ms Farrow-Smith had suffered a significant number of mosquito bites at Yamba was not put to her directly. Nor was it sufficiently clearly implicit in the questions she was asked about Dr Hannah's notes to make later reliance on the proposition fair. Ms Farrow-Smith had in fact given evidence directly to the contrary of this proposition in her witness statement dated 14 April 2021 at [78]: "I did not get bitten by mosquitos [sic] at Yamba". She adopted this statement in her evidence in chief. She was not challenged on this aspect of it.
56 It will also be recalled that Dr Gover's July 2020 report noted his understanding that Ms Farrow-Smith had been bitten by mosquitoes at Yamba. In cross-examination, Dr Gover was taken to notes he made on 6 July 2020 which recorded that "when first diagnosed reports being in yamba [sic] about one month before being seen and 'smashed by mosquitos'". Dr Gover agreed with a suggestion by the cross-examiner that this was a matter he would have spoken to Ms Farrow-Smith about on 6 July. If this is taken to mean that Dr Gover's understanding of events at Yamba came from Ms Farrow-Smith, it was evidence of another prior inconsistent statement by her. It was not raised with her in cross-examination.
57 The Tribunal appears to have regarded this evidence as significant. At [256] of its reasons it observed that "Dr Gover refutes the Applicant's case that she was not 'smashed' by mosquitoes at Yamba" (emphasis in original). Dr Gover, of course, could not give any direct evidence about what happened to Ms Farrow-Smith at Yamba. The Tribunal was evidently relying on Dr Gover having taken a history from Ms Farrow-Smith (consistent with what was in his notes and his report) as persuasively contradicting her direct evidence of what occurred. It did this without anybody having put to Ms Farrow-Smith that her evidence was incorrect in this important respect.
58 In these respects, the Tribunal failed to afford procedural fairness to Ms Farrow-Smith. Subject to the issue to be discussed next, its decision should be set aside.
59 In judicial review under s 75(v) of the Constitution and its analogues, where a grant of relief depends on establishing jurisdictional error, a failure to provide a fair procedure is regarded as going to jurisdiction only if it is shown to have denied the applicant a prospect of a successful outcome. This is an aspect of the doctrine of materiality as explained in recent cases including, for example, MZAPC v Minister for Immigration and Border Protection [2021] HCA 17; 273 CLR 506. The analysis is different in an appeal on questions of law, where the error identified need not be one that goes to jurisdiction. A failure to afford procedural fairness is an error of law for the purposes of s 44 of the AAT Act: Clements v Independent Indigenous Advisory Committee [2003] FCAFC 143; 131 FCR 28 at [6]-[8] (Gray ACJ and North J). However, an error of law does not justify an order under s 44(4) setting aside the decision of the Tribunal unless the error rises above a threshold of materiality. In Comptroller-General of Customs v Pharm-A-Care Laboratories Pty Ltd [2020] HCA 2; 270 CLR 494 the High Court (Kiefel CJ, Bell, Gageler, Keane and Gordon JJ) found that the Tribunal had erred in law but then continued, in language very similar to that used in the s 75(v) cases (at [40]):
However, it does not follow that the Comptroller-General's appeal to the Federal Court from the decision of the Tribunal ought to have succeeded. That is because, for an error of law on the part of the Tribunal identified in an appeal on a question of law to the Federal Court to result in an order setting aside the decision of the Tribunal, the error must be shown to be material to the decision of the Tribunal in the sense that the decision which was in fact made by the Tribunal might have been different if the error of law had not occurred.
60 It is therefore necessary to address the broader problem that Ms Farrow-Smith's case in the Tribunal faced. If that problem was insurmountable, it would follow that the provision of a fair hearing on the issue of whether she had suffered mosquito bites at Yamba in March 2020 could not have made a difference to the outcome.
61 The starting point is that Ms Farrow-Smith was only entitled to compensation under the SRC Act if the relevant decision maker (the Tribunal) was satisfied that she had suffered an injury for the purposes of s 14. As a result, although it is usually unhelpful to refer to concepts of onus of proof in an administrative tribunal, the Tribunal needed to be persuaded that the relevant causal link between the condition that she suffered and her employment existed.
62 Ms Farrow-Smith's Statement of Facts, Issues and Contentions (SFIC) noted that she had lived in the Northern Rivers area for several decades without being infected with RRV and that her home "provided limited opportunities for virus carrying mosquitoes to infiltrate" (at [3.6]). The SFIC then contended (at [3.8]):
It is not necessary to exclude every circumstance in which Ms Farrow Smith may have been bitten by mosquitoes.
63 It is fairly clear, therefore, that Ms Farrow-Smith was not seeking to persuade the Tribunal that the days on which she filmed flooding in the course of her employment were the only occasions on which she could potentially have been infected. In support of this position the SFIC cited South Australia v Roberts [2018] SASCFC 25; 130 SASR 274 at [122] (Parker J) (Roberts).
64 The respondent in Roberts was required to spend time in Oodnadatta (which is in a remote area of South Australia) for the purpose of her employment and stayed in accommodation arranged by her employer. The accommodation had inadequate insect screens and was so hot that the respondent needed to open the windows. She sustained mosquito bites. Soon afterwards she was diagnosed with an illness that was either reactive arthritis or inflammatory polyarthritis. There was a finding of fact that the condition was highly likely to have been caused by a mosquito bite, and there was a strong temporal association between the bites suffered at Oodnadatta and the onset of symptoms. The relevant legislation defined the term "injury" to include a "disease" and provided for compensation for an injury if it "arises from employment". It was further provided that an injury "arises from employment" if "the injury arises out of or in the course of employment and the employment was a significant contributing cause of the injury" (emphasis added).
65 Roberts came before the Full Court of the Supreme Court of South Australia as an appeal on a question of law from the South Australian Employment Tribunal. The issues in the appeal concerned whether the tribunal had properly applied the statutory test in circumstances where the relevant injury occurred while the respondent was in the place where the bites occurred as a result of her employment albeit not performing work at the time. Before the Tribunal in this case, Ms Farrow-Smith relied on the following statement by Parker J (with whom Blue J agreed) at [122]:
As this is an appeal on a question of law, the finding that the Full Bench correctly applied the statute is enough to decide the matter. Nevertheless, I take the opportunity to note that if this appeal had extended to questions of fact, I would have concluded that the Deputy President did not err in concluding that the respondent's employment was a significant contributing cause of her injury. The medical evidence establishes that the respondent's illness was caused by mosquito bites. Those bites occurred because she was housed in unsatisfactory accommodation in an extremely remote location that was arranged or paid for by her employer. She was present in that location for the sole purpose of carrying out her duties as an employee. In those circumstances, whether or not she might have been bitten by disease carrying mosquitoes at her home or workplace in Adelaide is not to the point.
66 This, with respect, does not assist in the present case. Apart from the statement being clearly obiter, it addressed a situation in which the mosquito bites that caused the respondent's illness ("those bites") were found or assumed to have been sustained in the accommodation arranged by her employer. In contrast, in the present case the key issue of fact was whether the Tribunal should be satisfied that the bites suffered by Ms Farrow-Smith in the course of her employment were the bites that infected her with RRV.
67 The critical words of s 5B(1) of the SRC Act ("that was contributed to, to a significant degree, by the employee's employment") are words that, given their ordinary meaning, refer to a causal link that exists in fact. There are many decisions of this Court and the Tribunal considering how close that causal link needs to be in order to satisfy the description "contributed to, to a significant degree". All of these (so far as I have been able to ascertain) proceed on the basis that a causal link needs to exist in fact for the condition suffered by an employee to constitute a "disease" as defined. In Comcare v Canute [2005] FCAFC 262; 148 FCR 232 at [63] (Canute), French and Stone JJ said (in relation to a predecessor of s 5B which only required contribution "in a material degree") that "a causal connection is always necessary between the employment and the contraction of the disease". (Canute was overturned on appeal (Canute v Comcare [2006] HCA 47; 226 CLR 535) but not on this point.) More recently, in Comcare v Martin [2016] HCA 43; 258 CLR 467, French CJ, Bell, Gageler, Keane and Nettle JJ construed the phrase "as a result of reasonable administrative action" in s 5A(1) as taking its content, in the case of a disease, from s 5B(1). The result was that "an employee has suffered a disease 'as a result of' administrative action if the administrative action is a cause in fact of the disease which the employee has suffered" (at [45]). It is implicit in this reasoning that s 5B(1) requires causation in fact.
68 As a result, it was not sufficient for Ms Farrow-Smith to show that RRV is carried by mosquitoes and she was bitten by mosquitoes on a particular day while performing her duties. It was not in doubt that mosquitoes were common in the Northern Rivers region and RRV was endemic. The Tribunal needed to be convinced that Ms Farrow-Smith's infection resulted from bites that she received in the course of her employment (or in circumstances connected with it) and not from a bite received in some unrelated setting. As noted earlier, Ms Farrow-Smith gave evidence about her home, directed at showing that steps had been taken to minimise the presence of mosquitoes there. She also gave evidence that she did not recall being bitten by anything in March 2020 and spent most of her time at home. The Tribunal did not find this helpful, noting that it had "no detailed information about the daily movements of the Applicant" (at [267]) and emphasising evidence of Dr Navin that "wherever one may be, and whatever time of the day it might be and wherever a person may be located, a mosquito, if it has close access, will feed" (at [268]). Given these findings and the state of the underlying evidence it appears that, even without the inference drawn from Dr Hannah's notes that she suffered a significant number of bites while at Yamba, Ms Farrow-Smith would have had significant difficulty persuading the Tribunal that her RRV infection should be attributed to the mosquito bites she sustained while filming.
69 I am not satisfied, however, that this difficulty was insurmountable. Comcare did not submit that it was necessarily a complete barrier to success for Ms Farrow-Smith. A case concerning the causes of a disease will rarely be able to be proved with certainty by eliminating all possible origins but one. Hence, in Coward v Military Compensation and Rehabilitation Service [2006] FCA 840; 153 FCR 535 at [34] Cowdroy J said:
This finding [that there was no evidence other than timing linking the applicant's condition with his employment] does not mean that a person claiming compensation would always need to demonstrate the exact event which caused an illness to occur, or be able to show with certainty which activity was the cause. If, for example the applicant in this case had demonstrated that an epidemic of gastro-enteric infections had been experienced at the barracks during the four-month period preceding the onset of his symptoms, the Tribunal may have been able to conclude that it was most likely to have been a gastro-enteric infection contracted in the course of employment which was the cause of his reactive arthritis.
70 In the present case, had Ms Farrow-Smith's evidence been accepted, it would have been open to the Tribunal to find that the multiple mosquito bites she received while filming in the course of her employment were most likely to have been the source of the RRV infection. Such a finding would be at least logically possible if the Tribunal accepted that apart from this event Ms Farrow-Smith was rarely if ever bitten by mosquitoes. The expert evidence as construed by the Tribunal weighed heavily against, but did not entirely exclude, such a finding. As noted earlier, the Tribunal was somewhat dismissive of Ms Farrow-Smith's evidence in this regard. However, there is a realistic prospect that the case could have taken on a different complexion if Ms Farrow-Smith had been given a proper opportunity to confront the suggestion that she had been "smashed" by mosquitoes at Yamba (and that her evidence was therefore incorrect). In Nathanson v Minister for Home Affairs [2022] HCA 26; 276 CLR 80 at [33] Kiefel CJ, Keane and Gleeson JJ observed that the standard of "reasonable conjecture" (the test for materiality in s 75(v) contexts) is "undemanding" and usually satisfied if a party is denied an opportunity to present evidence on a relevant issue.
71 While Ms Farrow-Smith's case in the Tribunal clearly faced significant difficulties, it was not bound to fail. The failure to afford her procedural fairness was therefore material. It requires that the decision of the Tribunal be set aside.