In May 2024 the Western Australian Supreme Court revised its practice and procedure (Practice Directions) in relation to expert evidence.

First mentioned in the notice to practitioners is the adoption of the Harmonised Expert Witness Code of Conduct, by which the WASC joins the Federal Court and the Supreme Courts of ACT, NSW, Tasmania, and Victoria.

At the same time as it harmonises, however, the Court has also found some new approaches.  Two are noteworthy.

Scope, purpose and facts to be set out in writing

A party seeking leave to introduce expert evidence will be required to prepare a “minute,” setting out:

• The field of specialised knowledge of the proposed expert.
• the specific questions on which the proposed expert will be asked to opine.
• the assumptions that the expert will be asked to make for each question.
• the facts which are relevant to the expert opinion.

The other party will have the opportunity to express disagreement with those matters, in which case the court will adjudicate by directions hearing.

Comment: The PD requires specific questions and underlying assumptions to be formulated at a much earlier stage – a contrast to matters as New Aim Pty Ltd v Leung [2023] FCAFC 67 where the questions were not formulated until the day before the report was finalised. Those who prefer to know the answer before they ask a question may involve “shadow” (or “consulting” or “dirty”) experts more often.   

Conclave or Conference?

Most of us would regard “expert conclave” and “expert conference’ as interchangeable terms to describe the standard meeting of experts which produces a joint report setting of details of any differences in the experts’ opinions.

In Western Australia however, conclave and conference will describe two different, if similar, processes.

A conclave is a conference facilitated by a Registrar of the Court.  It will follow an agenda that will be agreed by the parties (or determined by the Court in a directions hearing) and includes strict confidentiality rules and communication protocols – which seemingly do not apply to conferences.

A conference is unfacilitated – or facilitated by someone other than a Registrar.  It will address differences in the reports, rather than follow a specific agenda.

Comment: The Conclave process will be attractive for those seeking to focus on a tight range of issues or facing a situation with significant differences between the experts.  Parties who seek a level of communication with the experts during the preparation of the Joint Report may prefer the conference pathway which is not subject to the strict confidentiality regime (noting that the conference process still maintains the requirement that experts “shall not act on any instruction or request to withhold or avoid agreement”).

In an earlier blog I wrote about the decision in Elanor Funds Management Ltd v Alceon Group Pty Ltd [2023] FCA 1291, a matter in which a claim by the purchaser of a shopping centre  – who said that it has suffered loss and damage due to its reliance on information provided by the vendor – was unsuccessful.

The Court found that the purchaser’s valuation expert was not truly independent, although notably it specifically declined to criticise him for accepting the engagement.  However, the Court was critical of “unnecessary negative comments” which he made about his counterpart in a response affidavit, and a question he asked of his counterpart in the concurrent evidence session, which was said to demonstrate that he was acting “as an advocate.”

In Elanor Funds Management Ltd v Alceon Group Pty Ltd [2024] FCAFC 121 the Full Court reversed the original decision, finding for damages in favour of the purchaser.

The Full Court described the conclusion of the defendant’s valuer – that the market value of the centre significantly exceeded the transacted price agreed by two well-advised, sophisticated parties – as “surprising,” and preferred the evidence of the purchaser’s valuer.

The Full Court found that there was no sound basis to conclude that the “negative comments” were unnecessary.  In relation to the question asked of the other expert in the “hot-tub” the Court held:

The question [the purchaser’s valuer] asked was relevant. It was open to conclude that the raising of the question tended towards advocating rather than giving impartial evidence. However, it should be recognised that the evidence was given in the cut and thrust of litigation, more specifically in giving concurrent evidence where one expert might seek to convey why he considers his opinion to be preferable to the opinion of the other. This was the first time [the purchaser’s valuer] had given evidence in Court. Ultimately, it is a careful examination of the facts, the reasoning underlying the opinions, and the rationality of the views expressed, which is the surer guide to the correct outcome than the manner in which one particular piece of evidence is given or the fact that a witness temporarily lost his cool or slipped into a transient moment of what could be seen as advocacy.

Happily for the valuer, the Full Court held that the adverse credibility finding implicitly made against him “ought not have been made.”

A big story compressed into three hours of television means something gets squeezed out – so you can watch the excellent BBC series Mr Bates vs the Post Office (released in Australia in February 2024) without realising that expert evidence played a key role, or that the evidence of one expert was subject to very severe criticism.

Background

Each month UK Post Office sub-postmasters (effectively franchisees, the SPMs) were required to input details of stock and cash on hand into an accounting system called Horizon, owned and operated by an IT company, Fujitsu. 

Those actual figures were compared to the amounts that the Horizon system calculated as expected balances. If the actuals were less than the expected balances, Horizon identified the difference as a shortfall, which SPMs were contractually required to make up – presumably on the assumption that a shortfall reflected either a cash withdrawal from the till, or a sale that had not been correctly processed through the till.

Some of the SPMs were prosecuted for theft because they did not (or could not) pay the shortfall amounts that Horizon calculated.  Some of the SPMs were prosecuted for false accounting because they entered incorrect details into Horizon, to reduce the amount that they would be required to contribute.

Affected SPMs formed an action group, They argued that Horizon was not a robust and universally accurate system, and that it produced incorrect information which should not have been relied upon, especially for criminal prosecutions, and initiated a class action against the Post Office

Expert Evidence issues

Bates & Ors v the Post Office Ltd (No 6: Horizon Issues) [2019] EWHC 3408 (QB) was a separate hearing, dealing solely with the operation and functionality of the Horizon system itself, and so the role of  IT experts was critical to the outcome.

Each expert witness had substantial industry experience, and significant experience as an expert.  They prepared separate reports, supplementary reports, and then worked together to produce four joint reports.

“Shadow Experts”

The Post Office cost budget allowed £500,000 for experts who, notably, were instructed directly by the Post Office – not their solicitors or counsel – and who would not actually be giving evidence.

The Court said that direct instruction by a party was “a highly unusual situation,” and that estimated costs “were extraordinarily high, unreasonable and disproportionate,” which “did not, on the face of it, appear to be properly recoverable sums in the litigation.”

Direct Communication with the trial judge

The Post Office Expert prepared a second supplementary report, which he sent direct to the court, by email, after the trial had commenced.

The Court said that it was “extremely unusual, if not verging upon unheard of” for an expert witness to communicate directly with the trial judge rather than through the solicitors that engaged them. 

Although experts have a positive obligation to prepare a supplementary report if they change their opinions, in this case the Court held that the report was not due to a change in opinion, but rather an attempt “to bolster” existing conclusions.

Criticism of the Post Office Expert

The Court was not “universally critical” of the Post Office Expert.  It was careful to note that he had performed “a substantial amount of detailed analysis in his two reports” and played his part in significantly increasing “the overall knowledge that the court had.”  It recorded that he had also “discovered some bugs himself…[and] also took a sensible and considered view of some elements of the documentation,” and that his agreement in the Joint Reports had “saved a considerable amount of court time.”

Nonetheless, there was severe criticism of the Post Office Expert:

• His methodology was “wholly flawed…and obviously so,” using reasoning that was “entirely circular.”
• His analysis was “so riddled with plainly insupportable assumptions as to make it of no evidential value. It is the mathematical or arithmetic equivalent of stating that, given there are 3 million sets of branch accounts, and given there are so many sets of branch accounts of which no complaint is made, the Horizon system is mostly right, most of the time. It is a little more sophisticated than that, but not by very much.”
• He “took a partisan view of the evidence of fact…an obvious preferring of the evidence of fact of the party instructing him, added, in this case, to a refusal or failure to accept further evidence of fact to the contrary which subsequently emerged.”
• He relied “heavily” upon information from a Fujitsu executive whose involvement in the report “was simply hidden…[without] a note or summary of all the information that” the executive had provided.

Outcome

The Claimants were successful in that decision, the last of the reported judgements. 

In 2019 the Post Office agreed to pay compensation of £58m to the claimants. In 2021, the UK Government initiated a statutory inquiry by a retired high court judge, which is still underway.  In January 2024 the Government announced an intention to pass legislation to squash the SPM convictions, and passed legislation to set up a compensation scheme for the affected SPMs.

[edit on 5 October 2024 to note that this decision was overturned on appeal, see my blog here]

Background

The Purchaser of a neighbourhood shopping centre alleged that the vendor’s conduct was misleading and deceptive due to a claimed failure to disclose the true position of rental arrears, incentives and delayed lease commencements.  It claimed damages of $6m, which it calculated as the difference between the purchase price it paid on settlement, and the claimed “true” value as determined by an expert valuer engaged by the Purchaser (the Valuer).

In Elanor Funds Management Ltd v Alceon Group Pty Ltd [2023] FCA 1291, the Purchaser was comprehensively unsuccessful.  First, the Court did not accept that the Purchaser had established that the information was misleading and deceptive.  Secondly, it did not accept that the Purchaser had relied on the information.  Thirdly, it did not accept that the Purchaser had suffered a loss, because it preferred the valuation evidence of the Vendor’s expert valuer.

In dealing with the valuation evidence there were questions about the independence and impartiality of the Valuer, and the specific and detailed assessment of that issue are my focus here.

Multiple valuations and multiple values

The Valuer had provided three different valuations of the shopping centre as at the settlement date, on three separate occasions.

Firstly, he was engaged by the Purchaser in 2017 to prepare a valuation for mortgage purposes, which assessed the value as $55.25m.  He was also engaged by the Purchaser in 2021, to prepare a “retrospective indicative valuation” under specific assumptions, which assessed the value as $51m. Lastly, he was engaged a third time as an independent expert witness by the Purchaser’s solicitor in 2022, to prepare a valuation to support the damages claim, which assessed the value as $49m.

A well-qualified valuer who acted honestly

The Court found that the Valuer was a well-qualified, experienced, and professional valuer who had honestly approached his work, and in his evidence had answered questions in a straightforward manner without evasiveness, and had repeatedly made appropriate admissions.

…but not impartially

Notwithstanding that it accepted his expertise and honesty, there were concerns about the actions of the Valuer, who, the Court held:

• Was prepared to adjust his valuation calculations at the request of the Purchaser, which reflected “against his ultimate independence as an expert witness.”
• Understood “that the purpose of his engagement was to assist [the Purchaser] in litigation by deriving a lower figure than the purchase price for the centre.”
• “Did not act as one would expect an independent expert witness to act in the preparation of a valuation opinion…[and was] an active participant in assisting [the Purchaser].”
• Had made unnecessary negative comments about the relevant experience of the Vendor’s expert in a response affidavit, which were not a matter for reply evidence and were “a further basis for questioning his independence.”
• Asked a question in the concurrent evidence session about the Vendor’s expert’s registration, which, the Court held, demonstrated his role as an advocate for the Purchaser.

Notably, despite those concerns, the Court specifically declined to personally criticise the Valuer for accepting the expert witness engagement, for two reasons.  It noted that it was his first engagement as an expert witness, and further, noted that the Purchaser’s solicitor was aware that he was not independent, as evidenced in a letter of engagement, which noted “Given that you have already provided advice to [the Purchaser] in respect of its acquisition of the Centre, it cannot be said that you are truly an independent, arms-length expert.”

Comment

“Hot tubbing” is the informal name used to describe expert witnesses giving evidence at the same time, “concurrent evidence” is the formal term.  It allows counsel to ask the experts to comment on each other’s answers in real time, and judges to develop a conversation between two experts to discuss, for example, how and why they hold different positions.  Sometimes experts will be given the opportunity to ask each other questions.  This is the first judgement I have seen reflecting attention being paid to an expert’s question rather that his or her answer.

Background

In a previous blog I wrote about the decision in Robinson v Liverpool University Hospital NHS Foundation Trust v Mercier – which resulted in a £50,543 third party costs order against a dental expert witness who was subject to severe criticism, including the observation that his evidence was “simply absurd.”

The expert had expressed the opinion that a dental surgeon’s examination was deficient because it did not identify that the referral and x-rays (which recorded a tooth that in fact had already been removed) were both out of date.

Under cross-examination, the expert had agreed that since the patient was under general anaesthetic when the error was discovered – and hence could not be consulted – that the conservative course was to leave the tooth in place.  It seems likely that it was that concession which resulted in the patient claim being withdrawn – but that is speculation on my part, the Court did not make a specific finding.

The Appeal

In Robinson and Liverpool University Hospitals NHS Trust and Mercier [2023] EWHC 21 (KB) the High Court held that:

• It was true that the expert was not a maxillofacial surgeon – but the procedure was one that would have been carried out by a general dental practitioner but for the patient’s “morbid fear of dental procedures,” and there was no suggestion that it was not within the competence and scope of the clinical practice of a general practitioner dentist.
• There was nothing illogical or partisan about the expert’s conclusions, supported at least in part by the other expert and by the dental surgeon’s own acknowledgement of his error.
• The judge at first instance was wrong to conclude that the expert “had stepped outside the boundary of his expertise in giving his opinion about breach of duty and causation” and it was “not an exceptional case and did not involve a flagrant or reckless disregard of an expert’s duty to the court.”

The expert was successful in having the Third Party Costs Order set aside.

[Important update: From 1 September 2025 the Victorian County Court Commercial Division operates under updated case management rules, set out in the revised Omnibus Practice Note PNCO 1-2025 (the Practice Note).  The use of a single joint expert is no longer the mandated default position]

From 1 August 2022 the Victorian County Court Commercial Division operates under new case management rules, set out in the Omnibus Practice Note PNCO 2-2022 (the Practice Note).

As discussed below, there are significant changes to the role of expert evidence and the work of the expert witnesses.  Most notable are the default use of jointly instructed sole experts (broadly similar to the regime introduced in Singapore in April, discussed here, briefly), and the facilitation of conclaves where there is more than one expert.

The previous position

Under the previous regime in the County Court:

• There was no restriction on the use of expert evidence.
• Each side selected their own expert, and formulated the questions (including assumptions) that they wanted the expert to answer.
• The Court had power to order experts to confer and produce a Joint Report.
• The experts would give evidence concurrently (i.e., side by side: colloquially known as a “hot-tub”).

The post 1 August 2022 position

From a (non-lawyer) expert’s point of view the significant changes in relation to expert evidence are:

• No expert evidence without permission – A party wanting to introduce expert evidence must obtain permission of the Court, by an application which provides “brief reasons explaining why expert evidence is required.”
• Sole joint expert by default – The application must identify whether the parties agree on a single joint expert (the default position) or “whether it is contended that the appointment of more than one expert is appropriate.”
• Selection of the sole joint expert – each party will table a list of up to three candidates, with the Court to determine the appointee if there is no agreement between the parties.
• Brief to the sole joint expert –The plaintiff will prepare a document setting out a list of proposed questions, proposed assumptions, and a list of the documents to be provided to the expert. The parties will confer and seek to agree on those matters, with the Court to determine those questions if there is no agreement.
• Objection to the evidence of the sole joint expert – A party dissatisfied with the qualifications, impartiality or evidence of the sole joint expert may object by giving written notice within 28 days of the receipt of the report; and they may seek leave to adduce other or additional expert evidence.
• Joint expert conclave and report – If there is to be more than one expert, then absent orders to the contrary those experts will each prepare a separate report (as before), and will then meet in conclave, which may be facilitated by a judicial registrar or Commercial Division lawyer, to produce a joint report (in a “Scott Schedule”[1] format where appropriate).
• Communication whilst the joint report process is underway – The default orders include a very clear prohibition on communication between the parties, their employees, agents, and legal representatives, and the experts, until the joint report has been finalised.
• The role of a facilitator – the default orders provide that:
  • The facilitator is to chair the expert conference.
  • The facilitator may request from the parties “such further information or direction as the facilitator considers appropriate.”
  • Subject to any order, the facilitator shall be responsible for the precise form of the joint report
• Complex Cases List – The default orders for the Complex Cases list specify that any conclave is to be chaired and conducted by a facilitator.

My comments on the changes

1. The requirement to obtain permission to introduce expert evidence does not seem onerous: there’s no Singapore-style pre-condition that expert evidence must “contribute materially to the determination of an issue in the case.”
2. The appointment of a single joint expert may be very helpful where the facts are clear and the assumptions straightforward, but may be problematic in situations where determining the facts is a central issue of the litigation.
3. The sole joint report will, by intention, be unchallenged and uncritiqued, and so the Court will lose the benefit of each expert’s critique of the other’s report, as occurred under the previous regime.
4. Explicit endorsement of the Scott Schedule format (which I like) will help to spread its use.
5. The availability of a facilitator for conclaves is noteworthy. In my experience, most conclaves are conducted in a constructive and collegiate way.  On occasion I’ve felt frustrated about what appears to be a counterpart’s fixed adherence to a position (noting that in fairness I can’t claim to be an unbiased observer!) – but I haven’t experienced a facilitated conclave, so I have no insight about whether facilitation solves that problem.
6. The Practice Note explains that the changes are expected to result in cost savings:
   

   Parties should expect to incur greater expense in the process of engaging and instructing the single joint expert, but significant savings in having to contribute only a proportion of the costs of a single expert, both for the preparation of any expert report and at trial.
   

   There may be circumstances where those savings are offset by the increased use of behind-the-scenes “shadow” (or “dirty”) experts, to provide advice about the framing of the questions and the agreed assumptions; and there will also be costs in the event of an objection to the evidence of the sole joint expert.

[1] Defined in the Practice Note Dictionary as “a form of landscape table which sets out each claim and the contention of each party or expert with respect to it. Scott Schedules are named after their inventor, his Honour George Scott, Official Referee of the UK High Court of Justice 1920 – 1933.”