Federal Court of Australia

McNickle v Huntsman Chemical Company Australia Pty Ltd (Evidentiary Ruling) [2023] FCA 1268

RULING

THE COURT RULES THAT:

1.    The respondents’ application to exclude the opinion evidence of Dr William Sawyer pursuant to s 135 of the Evidence Act 1995 (Cth) be refused.

Note:    Entry of orders is dealt with in Rule 39.32 of the Federal Court Rules 2011.

REASONS FOR RULING

(Delivered ex tempore, revised from the transcript)

LEE J:

A    INTRODUCTION

1    An issue has arisen with respect to the admissibility of opinion evidence given by Dr Sawyer, an expert witness engaged by the representative applicant (Mr McNickle) in this class action concerning the alleged carcinogenic effects of Roundup weedkiller (Roundup).

2    It is unnecessary for the purposes of this ruling to set out in any detail the background to this proceeding (which has been canvassed in several judgments of this Court), save to note that the initial trial of common questions has reached a stage where, subject to documentary tender and the reading of a formal affidavit of two experts (which are not the subject of cross-examination), the parties are about to close their cases.

3    One of the scientific conclaves, “Conclave F”, which concerns exposure and absorption, had been anticipated to take place over 9 and 10 October 2023. Dr Sawyer and Dr Driver, an expert witness engaged by the respondents (collectively, Monsanto), were to give evidence in Conclave F.

4    However, at 5:31pm on 6 October (that is, last Friday evening), the solicitors for Monsanto (Freehills) notified the Court and the solicitors for Mr McNickle (Maurice Blackburn) by email that Monsanto did not intend to call Dr Driver and, accordingly, the anticipated concurrent evidence session became unnecessary.

5    At 5:45pm on the same evening, Maurice Blackburn responded to Freehills. Maurice Blackburn indicated that Mr McNickle did intend to rely upon the evidence of Dr Sawyer, including his expert reports and parts of the Conclave F joint report (Joint Report) which, in its present form, redacts any opinions of Dr Driver.

6    As anticipated, Dr Sawyer was called by Mr McNickle (in the trial and not on the voir dire) and then was cross-examined at length by counsel for Monsanto, Mr Craig KC. At the conclusion of the cross-examination, an application was made by Monsanto as explained below.

B    DR SAWYER’S EVIDENCE

7    It would not be an unfair characterisation of the cross-examination to say that a direct and concerted attack was made on Dr Sawyer’s independence in providing opinion evidence. It is appropriate to focus on five aspects of it that were referred to in argument today.

8    First, it is apparent that prior to giving evidence today, Dr Sawyer has prepared over 100 reports, spanning 49 proceedings in which there has been a deposition or trial, in litigation concerning the alleged carcinogenic effects of Roundup: T1968.36–1969.2. In those proceedings, Dr Sawyer expressed a view (to which he has adhered for a considerable period) that glyphosate, a key ingredient in Roundup, is carcinogenic to humans.

9    Secondly, and relatedly, Dr Sawyer has a fixed view, including at the time of preparing the Joint Report, that Monsanto has engaged in unethical and, indeed, criminal conduct in seeking to interfere with the publication of scientific research concerning the alleged carcinogenic effects of glyphosate. During the cross-examination, Dr Sawyer referred to several emails he received which were said to corroborate these serious allegations, although none of them were produced or provided to me during cross-examination (understandably) or thereafter in re-examination (for reasons I will not speculate about). Dr Sawyer further expressed the view that persons acting on behalf of Monsanto, at one point or another, had searched through or stolen his rubbish.

10    Thirdly, it was put to Dr Sawyer that he was not in a position to bring an independent mind to his opinion evidence because parts of his primary report dated 8 September 2021 (Primary Report) (specifically, section four of the Primary Report concerning general causation (“Responses to Toxicological Questions”)) amounted to a “cut and paste” job of sections of reports he had prepared previously for the purpose of Roundup litigation in the United States.

11    Fourthly, it was submitted that Dr Sawyer misapprehended the role of an independent expert as that concept is understood in the Anglo-Australian legal system. There was reference made to an exchange in cross-examination concerning the difference between how expert opinion evidence is adduced in the United States, and in this Court under the Expert Evidence Practice Note (GPN-EXPT). In short, save for the fact that he was asked to answer specific questions in writing which had been settled by the Court, Dr Sawyer indicated that the approach to giving expert evidence in this Court was broadly the same approach he has taken to giving expert evidence in the United States: T1989.29–1990.35.

12    Fifthly, it is apparent that Dr Sawyer has referred several other experts to testify for plaintiffs in Roundup litigation in the United States. It was submitted that Dr Sawyer had engaged in this process because he understood that those experts would give evidence broadly consistent with his view that glyphosate is a human carcinogen and that Monsanto is an unethical and criminal enterprise and, accordingly, that he was the polar opposite of the sort of “clean skin expert” to which I had encouraged the parties to retain in this proceeding: see McNickle v Huntsman Chemical Company Australia Pty Ltd (Expert Evidence) [2021] FCA 370 (at [18]).

13    In the light of the above, an application was made by Monsanto today pursuant to s 135 of the Evidence Act 1995 (Cth) (Evidence Act) to exclude Dr Sawyer’s evidence on the basis that it might give rise to a danger of unfair prejudice or be misleading or confusing, and that accordingly, the Court should exercise its discretion to exclude it.

C    “HIRED GUNS” AND EXPERT EVIDENCE

14    None of this is a bolt from the blue.

15    As long as two and a half years ago in McNickle v Huntsman (Expert Evidence), I anticipated that an objection will be made by Monsanto to the evidence of, inter alios, Dr Sawyer, who I described then (at [17]) as a witness:

[w]ho has allegedly given evidence in 28 proceedings apparently dealing with the Expert Issues.

16    I went on to note (at [18]) that:

Cognisant of potential issues of adversarial bias, particularly in a case such as the present involving allegations of scientific manipulation, on 22 December 2020 (and having abandoned the proposed reference), I indicated to the parties that the Court would be best assisted if the experts chosen by the parties in each area of speciality were non-partisan and were “truly independent about the issues and about their view”: see T9.43–7.

17    As I indicated to the parties then (at [21]), if there was to be some attack on the independence of, among others, Dr Sawyer, then, consistently with the overarching purpose in Pt VB of the Federal Court of Australia Act 1976 (Cth), it would be utile to ensure that any such objection was resolved sooner rather than later. During that discussion, I had referred to the possibility that it may be appropriate to make an order facilitating an advance ruling pursuant to s 192A of the Evidence Act.

18    As it happened, Mr McNickle opposed this course. As I explained then (at [32]):

Both in written submissions in advance of the case management hearing and orally, Mr Rush QC, counsel for Mr McNickle, submitted that it would be beyond power for the Court and the parties to embark on a process of presently determining whether any expert evidence which may be given by any expert witness would be excluded pursuant to s 135 of the Evidence Act or on admissibility grounds. Five points were made:

(1)     First, the “threshold jurisdictional” question for exercising the discretion in s 192A has not been satisfied. Section 192A may be enlivened where a “question arises” in relation to any of the three matters set out in subparagraphs (a)–(c) of that section. No such question presently arises. This is said to be because:

(a)     there is presently no “evidence” proposed to be adduced and thus, subparagraphs (a) and (b) of s 192A cannot apply; and

(b)     no question arises about the giving of leave, permission or direction under s 192: see s 192A(1)(c).

(2)     Secondly, further to the threshold issue, it would be inappropriate for the Court to exercise the discretion under s 192A at this time. Here, no expert reports have been filed, and as such, the Court would be making its discretionary decision in the absence of information which is critical to that decision. It was said that the Court is in no position to, and ought not to, make an advance ruling where all matters relevant to the issues have not been, and cannot be, ascertained.

(3)     Thirdly, difficulties arise in relation to any contemplated rulings since it is not clear what precise rulings would in fact be sought by Monsanto.

(4)     Fourthly, while it seems the process presently contemplated is intended to avoid disruption to the trial date, it will have the opposite effect. It was said that Monsanto appears to make a global complaint in respect of all of Mr McNickle’s experts, and as such, five experts would need to give evidence and be cross examined at a voir dire. The processes around production of documents and materials relevant to such a voir dire will take further time, and will inevitably lead to delay in the balance of the timetable to an initial trial.

(5)     Fifthly, Order 1 made on 5 March 2021 focuses the inquiry concerning the independence of the experts and whether those experts have expressed certain opinions previously. It was submitted that the questions posed indicated a misunderstanding of what is required by the notions of “independence” and “impartiality” in the expert evidence context. It was further submitted that even if an expert has expressed an opinion previously (even on many occasions), this does not mean that the expert is not independent or impartial within the court processes. It was said that it simply does not follow from the fact that an expert has extensive experience and expertise, and based on that experience and expertise has formed opinions about certain questions of science (which may have been expressed previously, including in previous litigation), that the expert lacks independence or impartiality. Accordingly, it was said that as a consequence, the rulings proposed are based on an incorrect premise.

19    The fifth point was repeated during oral submissions today: that is, any issues concerning a perceived lack of independence and impartiality cannot go to issues of admissibility but rather only to weight. In this respect, I was referred to the judgment of Wigney J in Rush v Nationwide News (No 5) [2018] FCA 1622 (at [35]–[36]), where his Honour noted:

[35]    The relevant principle established by those and other authorities was neatly summarised by Dodds-Streeton J in Ananda Marga in the following terms (at [35]):

In my opinion, relevant authority establishes that while (as reflected by the Federal Court Practice Note and like curial protocols) objectivity and independence are sought of expert witnesses, such qualities are not preconditions of competence, even in the case of expert witnesses. The sanction for failure to fulfil the obligations imposed by relevant authority and curial protocols is not the exclusion of the expert’s evidence, but rather, the significant risk that it will fail to persuade.

[36]    In other words, an actual or perceived lack of independence, impartiality or objectivity of an expert witness goes to weight, not admissibility.

20    In response to that argument, I expressed the following views in McNickle v Huntsman (Expert Evidence) (at [34]–[35]), to which I adhere:

[34]    In Rush, Wigney J (at [11]–[43]) dealt with what was described as “the independence ground”, which, unsurprisingly, was an argument advanced by the publisher in that case that the alleged lack of independence of two experts proposed to be called by the applicant in a defamation proceeding ought not be admitted or alternatively excluded. His Honour dealt with an argument that the applicant had not complied with Pt 23 of the FCR because, in the circumstances of the case, the expert was an advocate for the cause of the party who proposed to call him. In doing so, his Honour dealt with a decision of Mortimer J in Guy v Crown Melbourne Limited [2017] FCA 1104, expressing (at [36]) the view that:

… an actual or perceived lack of independence, impartiality or objectivity of an expert witness goes to weight, not admissibility.

[35]    I think Mr McNickle puts the point too highly. A broad point was being made by his Honour in Rush, which is no doubt correct in the general run of cases. But I do not think this means there cannot ever be circumstances in which a lack of impartiality or objectivity would go to more than weight and would form a basis by which the proposed expert evidence would not be admitted. One would conceive of some circumstances where proposed expert evidence could fail to survive the balancing exercise required when applying s 135 of the Evidence Act, in that receiving such evidence would be of such limited assistance (by reason of its lack of independence, impartiality or objectivity) that it would be unfairly prejudicial to the other party or would result in an undue waste of time.

21    As is evident from the above, the position that Mr McNickle took in the early interlocutory stages of this proceeding was clear: the Court can only, and must only, deal with any objections to the expert evidence in the context of the initial trial. I noted then (at [39]) that I had formed no view as to whether or not the objections foreshadowed had any merit, but that I was nonetheless conscious they had been advanced by responsible counsel and solicitors who had formed the view that there is a reasonable basis for saying there was a want of independence on behalf of the relevant experts such that their evidence should be the subject of (at least) discretionary exclusion. I went on to note (at [41]–[42]) that:

[41]    I did think initially that it was possible for an advance ruling hearing to be held some time prior to the initial trial if it was with the active cooperation of both parties and there was no objection to this course. However, given the opposition to this course by Mr McNickle, I am not convinced that this is appropriate. Indeed, there is some prospect that adopting this course would lead to a potential interlocutory appeal. If there had have been cooperation by both parties, I would have grasped the nettle and proceeded to have had an advance ruling hearing in advance of the initial trial, even if, at the end of that hearing, I was persuaded that it was inappropriate for a ruling to be provided. Given that course is opposed, then not without some misgivings, it appears that I will have to leave the ruling on admissibility of the expert material (on presently identifiable grounds) to the initial trial (as is said to be necessary by Mr McNickle).

[42]    As I stressed above, I have reached no view one way or the other as to whether or not any allegations of a lack of impartiality have any substance. No doubt Mr McNickle will maintain his contention that the evidence given by the nominated experts will be of importance in resolving the issues and carries great weight. All that is yet to be seen. Of course, if at the initial trial the objection which has now been clearly flagged is upheld, I will be required to determine the appropriate remedial response. In determining any remedial measure proposed by Mr McNickle, no doubt Monsanto will submit that its attempt to resolve this issue now pragmatically (which has been objected to) will be a relevant consideration in the event that the objection is ultimately upheld on the basis of material now known to exist or able to be obtained.

D    CONSIDERATION

22    The consistent position of Mr McNickle, expressed again today by Mr Clements KC, is that any notion of being concerned a party retains an expert who has a fixed opinion is misconceived. It was submitted that the proper approach is to consider the scientific material adduced from any expert and judge it on its merits, irrespective of whether the expert has adhered to a fixed view prior to being engaged to assist the Court or, indeed, irrespective as to whether the expert harbours some justified or unjustified animus towards a party.

23    It is unnecessary for me to deal with the underlying merit of this submission at present because, on balance, I think that the appropriate course is to admit the opinion evidence of Dr Sawyer.

24    There can be little doubt that an assessment of the weight of Dr Sawyer’s opinion evidence will be the subject of detailed closing submissions. One aspect of that assessment may involve consideration of the forensic decision not to call Dr Driver, another will be the evidence given by Dr Sawyer in cross-examination, including the evidence summarised at Section B above.

25    All these aspects, and others, will require close consideration. The points made by Monsanto today attacking the cogency of the Dr Sawyer’s evidence in the context of discretionary exclusion apply equally to the weight that should be afforded to that evidence. I do not propose to express any views here about the ultimate reliance that ought to be placed on the opinions expressed by Dr Sawyer or canvass any of the alleged deficiencies in the evidence relied upon by Monsanto. For the purposes of this ruling, it is necessary I form an impressionistic assessment of its probative value, but to descend into further detail without the benefit of final submissions in a matter such as this, involving complex scientific evidence, would be premature and inappropriate.

26    In exercising the discretion, I have had regard to s 192 of the Evidence Act. Without seeking to list all relevant considerations exhaustively, to exclude the evidence at this late stage of the initial trial would not shorten the length of any hearing. Relatedly, it is relevant that the forensic course taken by Monsanto was not to attack the evidence on the voir dire and then seek to object to the adduction of evidence in chief in the trial (being the more orthodox course), but to allow the evidence in at trial without objection and then seek to discredit and apply to exclude it. Further, weighing significantly in the exercise of discretion is that the topic of the opinion evidence is of some importance given the determinative issues in the proceeding.

27    In the end it must be demonstrated that the danger of unfair prejudice or relevant confusion substantially outweighs the probative value of the evidence. In the light of the potential probative value of the evidence and the reality that the matters now raised by Monsanto can be dealt with through the prism of an assessment of the weight of the evidence, I do not consider that unfair prejudice or confusion is established to a degree necessary to enliven the discretion to exclude the opinion evidence pursuant to s 135 of the Evidence Act.

E    CONCLUSION

28    Accordingly, Monsanto’s application to exclude the opinion evidence of Dr Sawyer is refused.

Associate:

Dated:    23 October 2023

SCHEDULE OF PARTIES