Assembly and management of expert evidence
The garnering of expert evidence, per se and in a form suitable to be adduced in court, was addressed in Landel Pty Ltd & Anor v Insurance Australia Ltd  QSC 247. Dalton J wrote:
 The cause of the inundation of the shopping centre on 3 and 4 February 2019 was the subject of expert evidence which occupied almost all the trial time. The plaintiffs relied upon the views of Dr John Macintosh and the defendant relied upon the views of Mr Ben Caddis and Dr Tom Connor. There were significant issues with the expert reports, and I will say something about them for the guidance of the profession.
 First, while lawyers must not coach expert witnesses, or influence the substance of an expert report so that it favours their client, it is permissible, and usually desirable, that lawyers do become involved in the editing of expert reports so that they present material in a way which is accessible and comprehensible, and do not contain irrelevant material. Draft expert reports are disclosable so that the effect of any such input will be obvious to the other parties to the litigation – see r 212(2) and Mitchell Contractors Pty Ltd v Townsville-Thuringowa Water Supply Joint Board.5
 In this case, Dr Macintosh’s reports are prolix and disorganised. There ought to have been conferences between Dr Macintosh and the plaintiffs’ lawyers before they were filed to see what could be done to improve these types of problems. Conferences like this are a proper, necessary part of preparing a case. In a proceeding like this I would expect that attention to have come from both the solicitors and counsel briefed in the matter.
 Any disciplined and structured conferences with Dr Macintosh would have revealed that there were faults in his opinions which went beyond matters of expression and presentation. They would have revealed significant contradictions, errors and gaps in reasoning in his reports. It is permissible for matters of substance like this to be drawn to an expert’s attention in conference with lawyers, and remedied if the expert is able and willing to do so. Again, coaching is not permitted, and drafts will be disclosable.
 The course of this proceeding shows the importance of attention to the reports of experts by the lawyers running the case, not just to achieve a comprehensible and rational expert opinion for use at the trial, but to evaluate the strength of the case sought to be advanced by the litigant. In this case, had early attention been paid to what reasoned opinion Dr Macintosh could give, the plaintiffs’ lawyers would have understood the weaknesses in their expert case at a stage of the litigation when there might still have been alternatives open to them. Instead, it appears that the only effort the plaintiffs’ lawyers made to come to terms with Dr Macintosh’s opinions was immediately prior to trial, by which time any such avenues were very limited. Thus, counsel for the plaintiffs said in his opening, “there’s more common ground than one might think from these reports” – t 1-28. By the time of closing addresses, counsel for the plaintiffs had all but abandoned reliance on Dr Macintosh’s views, describing them only as a “plausible theory” – t 9-15.
 Turning to the other side of the record, a peculiar arrangement was undertaken by solicitors acting for the defendant. Mr Caddis who is employed by an engineering firm, BMT Commercial Australia Pty Ltd, was engaged to prepare a report on the cause of the inundation, and so was Dr Connor, who is semi-retired and has never worked for BMT.
 Mr Caddis had earlier produced a report dated 7 March 2019 apparently on instructions directly from the defendant insurer, not the insurer’s lawyers.6 Criticism was made of Mr Caddis’ independence on this basis. It was said that he worked as a consultant to the insurance company rather than an independent expert aware of his duties to the Court. As a matter of general practice, I accept that this is potentially a legitimate basis for criticism. However, in this case, having regard to the substance of the expert opinions, discussed below, and Mr Caddis’ impressive and professional demeanour when giving evidence, it is not a matter which causes me any disquiet about Mr Caddis, or his opinions.
 The initial retainer of Mr Caddis and Dr Connor by the insurer’s lawyers was oral, in or around March 2019. I see no difficulty with an initial oral retainer, or indeed an initial oral exchange of views prior to the engagement of an expert.7
 After the retainer of Mr Caddis and Dr Connor, there were meetings between the two experts, the defendant’s solicitors, and apparently counsel, on between five and ten occasions.8 They preceded the delivery of any written report. I do not have any criticism of these meetings having taken place. However, I am critical of the defendant’s lawyers for meeting with both experts together. Lay witnesses should never discuss their evidence with each other. Experts see each other’s reports before trial, and sometimes there are Court-ordered conferences between expert witnesses. Here, where the plan apparently was to present two independent views to the Court, meeting with both experts together, particularly before they had committed their views to writing, obviously had the potential to compromise that independence.
 As to the idea that there could be two experts on the same subject matter called by the defendant, r 423 provides that a party will be limited to one expert opinion in a proceeding, unless leave is given. This rule was new when the UCPR was introduced in 2000. It was introduced because parties would sometimes obtain reports from several different experts who all practised in the same field. Quite often this occurred in personal injuries cases which, in those days, used to run to trial. This increased the costs and length of trial, and no doubt introduced a risk that the weight of numbers added authority to the opinions, see r 423(d).
 In a case like this, where expert opinion is crucial to the liability dispute between the parties, and the area of expert opinion is not one commonly encountered by the Courts, a Judge might well have given leave for the defendant to use two reports on the same topic. Certainly there was no objection from the plaintiffs to Mr Caddis and Dr Connor both giving opinions on essentially the same questions. This report was in evidence, although not as one of the reports relied upon by the insurer. It was apparently given by the insurer to the plaintiffs early on and was in evidence as part of the material which was briefed to Dr Macintosh when he was asked to prepare his first report. 7 It is recognised at para [212.20] of the LexisNexis annotations to the Uniform Civil Procedure Rules that since changes to disclosure rules to make expert opinion disclosable there has been a practice of orally engaging experts and receiving, at least their initial, opinions orally. Only if the expert’s initial oral opinion is favourable are documents produced. To my understanding this is a common practice and permitted by the rules. I note that the LexisNexis annotations include, “Although the consultation draft for the UCPR contained a provision that required the recording in writing and disclosure of expert’s oral opinions, that provision was ultimately omitted from the Rules.” If, when an expert is giving such an oral opinion, a solicitor takes notes, those notes are disclosable in my opinion. 8 In this regard I prefer Mr Caddis’ evidence, t 5-18. Dr Connor plainly struggled to recall the details of any meetings – t 6-30.
 There is a practice, particularly in large accounting cases, where it is not possible for one accountant to do all the work necessary to prepare an expert report, whereby the partner of a firm will sign an expert report, but acknowledge that other named accountants have performed various tasks which feed into his or her ultimate conclusions. Generally it is only necessary to cross-examine the accountant who signs the report and swears the affidavit in the proceeding. In such cases there is no objection to all the accountants involved conferring with lawyers together and working together. They are not purporting to give independent views, but working as a team.
 Here there was an undesirable, and confused process. By a letter dated 29 July 2020 addressed to both Mr Caddis and Dr Connor, solicitors for the defendant instructed them both to “prepare a co-authored written report”. The instructions include asking Mr Caddis to conduct flood modelling in respect of the inundation of the shopping centre on 3 and 4 February 2019. As well as being asked to give his opinion as to the cause of the inundation on 3 and 4 February, Dr Connor was instructed “to review and consider the results of Mr Caddis’ flood modelling … as well as the Macintosh report, and advise whether you agree with Mr Caddis’ findings”.
 This set of instructions led to one report being provided which was branded extensively with the BMT logo. It was, as the defendant’s solicitors had asked, in two parts. Part A bore the signature of Mr Caddis on page 56 above the date 7 August 2020. Pages 58 to 88 of the report were labelled Part B. It was in the same format as Part A and bore the same colours (shades of BMT blue) as the rest of the report in terms of headings and footers but, on careful inspection, did not bear the BMT logo. The same can be said for the pages of the report which give Dr Connor’s CV; although they have been put into a format closely resembling the pages which bear Mr Caddis’ CV. Dr Connor signed Part B on page 88, also dated 7 August 2020.
 The fact that the two expert views were presented as coming from one source – BMT – rather than being presented as two independent opinions points strongly in the direction of confusion being responsible for the way the solicitors and counsel conferred with both experts together before production of written reports, rather than some attempt to mislead, as was suggested by the plaintiffs’ counsel in addresses.
 Another undesirable consequence of the unusual instructions given to Dr Connor is that his report not only gives his opinion as to the cause of the inundation of the shopping centre (which is the legitimate subject matter of expert opinion in this case), it reviews the reports given by Dr Macintosh and Mr Caddis, at times, line-by-line. In accordance with his instructions, he assumes the role of some sort of uber-expert, or perhaps engineering-judge, in explaining why he prefers Mr Caddis’ opinions to those of Dr Macintosh. This is not the role of an expert witness.
 Nor is it the role of expert witnesses to concern themselves with the legal issues in the case. It is the job of the lawyers in any case to define questions upon which they seek expert opinion. This has to be carefully done so that the expert opinion obtained is relevant to the legal issues in the case. Unfortunately, in this case all the experts were briefed with the words of the insurance policy.
 Lastly, the plaintiffs pointed to the very short time between the formal written instructions and the dates of the first Caddis/Connor report. A submission was made that Mr Caddis and Dr Connor had not been properly retained and had prepared this first report by reference to material and instructions which were not placed before the Court. While I am not critical about lawyers meeting with experts, or potential experts, before there is anything put in writing, I do think it is good practice to brief an expert in writing once a decision has been made to retain them. To let matters progress as this one did, where the experts were plainly retained, and Mr Caddis at least was undertaking substantial work, before written instructions were provided, has the potential to give the impression that something ulterior is going on.
 While I understand the plaintiffs’ exploration of these issues, I do not accept the submissions made by counsel for the plaintiffs that Dr Connor and Mr Caddis were not independent of CGU.
 There was a vast gulf in the quality of expert opinion in the case between Dr Macintosh on the one hand, and Dr Connor and Mr Caddis on the other. As his reports presaged, Dr Macintosh was discursive and non-responsive in the witness box. He showed strong emotional attachment to his ideas. On the other hand, Dr Connor and Mr Caddis were responsive witnesses, who gave reasoned and logical explanations for their views both in writing and in the witness box. I do not doubt that they presented their honest opinions in their reports and in oral evidence. Dr Connor and Mr Caddis received unusual instructions and complied with them. I cannot see that the oddities which resulted are their fault. I have a strong preference for the opinions of Mr Caddis and Dr Connor over those of Dr Macintosh. I turn to the substance of their reports to explain why
6 This report was in evidence, although not as one of the reports relied upon by the insurer. It was apparently given by the insurer to the plaintiffs early on and was in evidence as part of the material which was briefed to Dr Macintosh when he was asked to prepare his first report.
7 It is recognised at para [212.20] of the LexisNexis annotations to the Uniform Civil Procedure Rules that since changes to disclosure rules to make expert opinion disclosable there has been a practice of orally engaging experts and receiving, at least their initial, opinions orally. Only if the expert’s initial oral opinion is favourable are documents produced. To my understanding this is a common practice and permitted by the rules. I note that the LexisNexis annotations include, “Although the consultation draft for the UCPR contained a provision that required the recording in writing and disclosure of expert’s oral opinions, that provision was ultimately omitted from the Rules.” If, when an expert is giving such an oral opinion, a solicitor takes notes, those notes are disclosable in my opinion (emphasis added).
8 In this regard I prefer Mr Caddis’ evidence, t 5–18. Dr Connor plainly struggled to recall the details of any meetings — t 6–30.