Examining whether opinions developed collaboratively are admissible


We look at the key lessons from BrisConnections Finance Pty Limited (Receivers and Managers Appointed) v Arup Pty Limited [2017] FCA 1268

The primary allegation in this case was that a traffic forecaster (Arup) provided misleading and negligent traffic forecasts, which were relied upon by BrisConnections, causing them loss.

What are the key takeaways?

  • It is preferable for an expert report to have a single author responsible for the opinions expressed, rather than a report co-authored by multiple experts, to make it clear which opinions are held by each expert and avoid possible criticism of “cross-pollination of specialised knowledge”.
  • By analogy, where multiple experts are required to address multiple areas of specialised knowledge, it is preferable for those experts to provide separate reports rather than a co-authored report.
  • Each expert’s report should identify any dependency on the reports or opinions of others and state that, where staff members have assisted in the preparation of the report or underlying analysis, that the opinions expressed are those of the expert, based on the application of their specialised knowledge and experience.
  • Where possible, instructions to experts should be formalised well in advance of their reports being finalised.

Overview of the case

This judgment provides commentary on the admissibility of a report signed by two experts (the Veitch Report) considering:

(a)        the problem of compromised opinions; and

(b)       s79 of the Evidence Act 1995 (Cth) in the context of complex expert reports prepared by more than one author and partly based on work performed by others.

Justice Lee held, to be admissible, opinions that were the result of "an application of the specialised knowledge of a proposed witness, but [which were] reached following discussion and debate between the expert and another".[1] Justice Lee accepted the Veitch Report as evidence, as the opinions expressed were held by Mr Veitch based on his specialised knowledge, and these opinions would have been developed, in part, by relying on the work of his team, particularly his son. Justice Lee also criticised the practice of issuing a letter of instruction after the work is substantially done or on the date a report is signed stating it “cannot be taken seriously”.[2]

BrisConnection’s evidence

BrisConnections tendered expert reports authored jointly by a father-son team of traffic forecasters. The opinion sought was whether a competent traffic forecaster, acting reasonably, would have produced Arup's forecasts.

Arup’s objection: “infected with the cross-pollination of ‘specialised knowledge”[3]

Arup’s objection was that, as a ‘joint’ opinion, “it was not apparent the opinions expressed were wholly or substantially based on the specialised knowledge of either Mr Veitch or his son and, as a consequence, the exception to the exclusionary Opinion Rule, contained in s 79 of the Evidence Act 1995 (Cth) (Act), was not engaged”. [4]

BrisConnections attempted to address Arup’s objection by reissuing the report under Veitch Snr’s hand (single expert rather than signed by two people) and changing all the personal pronouns to ‘I’ (the Revised Veitch Report).


Justice Lee accepted the Veitch Report as expert evidence as the opinions expressed were held by Mr Veitch based on his specialised knowledge, and these opinions would have been developed, in part, by relying on the work of his team, particularly his son.

In opining on the admissibility of the Veitch Report, Justice Lee concluded:

(a) That expert reports practically involve a degree of collaborative work and that it was unlikely the relevant work required would be completed within sensible time constraints without a team. 

(b) There is a greater need for collaboration / toing and froing within a team for larger complex litigation matters (with large volumes of data) in forming an opinion “[p]rovided the expert’s mind is applied to the analysis and reasoning processes which those working with the expert have developed, so that when the report is finalised it is apparent that the whole of the reasoning and conclusions it contains has been ‘adopted’ as the expert’s own reasoning and conclusions.”[5]

(c) Whilst Mr Veitch worked closely with his son, he was the “more experienced man”. Justice Lee did not “believe that Mr Veitch is someone who was likely to surrender the expression of his genuine views on any matter of significance to reach a compromise with his son.” [6]

“The Revised Veitch Report serves no useful purpose and I reject its tender.” [7]

Justice Lee rejected the Revised Veitch Report as evidence stating “When it is appreciated that it is both form and substance that matters…if the opinions are hopelessly compromised and have not been properly formed, the Gatling gun approach to destroying plural pronouns will not save the day." [8]

Justice Lee criticised the common practice, evident in this case, of providing a letter of instruction on the date a report is signed.

“The point of a letter of instruction being annexed to a report is not to act out a stylised ritual, but to provide to the Court with a transparent indication of what has been provided to the expert and the questions that the expert was actually asked to address. It should be able to be read literally without being silly. As is (at the very least) implicit in FCR 23, the work of the expert is to attend to the questions “the expert was asked to address”, not to invert the process by using the expert’s specialised knowledge in order to identify the questions that should have been asked and the assumptions that should have been given” [9]

Read the full judgment here: https://jade.io/article/561022


[1] Paragraph 48

[2] Paragraph 70

[3] Paragraph 32

[4] Paragraph 6

[5] Paragraph 53 and 64

[6] Paragraph 61

[7] Paragraph 66

[8] Paragraph 50

[9] Paragraph 71