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Cracks in the foundation stones of expert evidence: permission for expert revoked after ‘serious transgressions’ by expert and solicitor

In Andrews & Ors v Kronospan Limited [2022] EWHC 479 (QB), Senior Master Fontaine revoked the Claimants’ permission to rely on their expert after it was admitted that there were ‘serious transgressions’ by the expert and solicitors in relation to the expert’s joint statement. James Culverwell discusses the authorities which emphasise independence as the ‘foundation stone’ of expert evidence, and provides guidance for TCC practitioners.

By James Culverwell


The 159 Claimants in Andrews & Ors v Kronospan Limited [2022] EWHC 479 (QB) are all residents of Chirk near Wrexham, each of whom claim to have been caused a nuisance by dust from the Defendant’s wood processing plant.  In 2018, the court made an order granting permission for each party to have expert evidence from a dust modelling expert and from a dust analysis and monitoring expert.  The Claimants instructed Dr Nigel Gibson in both disciplines while the Defendant instructed Drs Carruthers and Datson respectively.

During the joint discussions between Dr Gibson and Dr Datson, Dr Gibson provided the Claimants’ solicitors with various working drafts of their joint statement and the solicitors provided comments on those drafts for Dr Gibson to implement.  Some 68 comments were made on the draft of which 16 were admitted as relating to substantive issues.  Dr Gibson even tried to include a note of evidence that he had produced for a conference with counsel, without having discussed such an inclusion with Dr Datson, or indeed counsel.  At one point, the Claimants’ solicitors responded to Dr Gibson saying that they had reviewed the draft as they understood he ‘wanted to ensure that it captures the points relevant for cross-examination’.

None of this was disclosed either to Dr Datson or the Defendant at the time.  Upon discovering potential discussions and pressing the Claimants solicitors, the conduct was eventually revealed and the Defendant applied to the court for the Claimants’ permission to rely on Dr Gibson to be revoked.

In written evidence and through counsel at the hearing, the Claimants accepted that—

  1. it was inappropriate for the Claimants’ solicitors to have provided comment solely to Dr Gibson, and that Dr Gibson should not have responded to those comments;
  2. it is wrong for an expert to solicit input from their instructing solicitors during the process of drawing up a joint statement, just as it is wrong for those solicitors to provide that input;
  3. there was a serious transgression of the rules by the Claimants, by reference to the terminology in the case of BDW Trading Ltd v Integral Geotechnique (Wales) Ltd [2018] EWHC 1915 (TCC);
  4. the court has power to revoke permission to rely on an expert.

Meanwhile, in the TCC…

It may be due to the quantity of cases requiring expert evidence, but the TCC unfortunately seems to lead the field on experts’ misfeasance and has provided three key authorities on the role and conduct of experts, all of which were considered by the Senior Master in Andrews.  As well as BDW Trading referred to above, the TCC dealt with unsatisfactory experts in Imperial Chemical Industries Ltd v Merit Merrill Technology Ltd [2018] EWHC 1577 and Dana UK Axle Ltd v Freudenberg FST GmbH [2021] EWHC 1413 (TCC).

In BDW Trading, the defendant’s expert in geotechnical engineering revealed in cross examination at trial that he had sent a first draft of the joint statement to the defendant’s solicitors and having received feedback, had made some changes to that draft as a result.  HHJ Stephen Davies sitting as a Deputy Judge of the High Court concluded that the expert was genuinely unaware that his conduct was inappropriate and emphasised that ‘it is important that all experts and all legal advisers should understand what is and what is not permissible as regards the preparation of joint statements.’  The judge explained that the TCC guide plainly envisages an expert providing a draft copy of the joint statement to solicitors but that the expert should not ask for general comments or suggestions on the content nor should the solicitors provide any, save in the limited circumstances set out in paragraph 13.6.3 of the TCC guide.

In Dana UK Axle, there was a ‘very serious’ breach of the rules by the defendant’s three technical experts which was discovered part way through the trial.  Some of the experts had already required an order granting them relief from sanctions upon certain conditions which, it transpired, had not been complied with.  Joanna Smith J found that the breaches of CPR Part 35, PD35 and the Civil Justice Council guidance was so serious, even without the failure to meet the conditions of relief, that the court should refuse to allow the defendant to rely on those experts.  Her Ladyship referred in the judgment to the decision of Fraser J in ICI v MMT, the third of the three TCC cases.

In ICI v MMT, Fraser J found that the employer’s experts were not independent having, amongst other things, ignored evidence from a key factual witness closely involved with the project who was not an employee of either party and also attempted to entirely reopen the Defendant’s account including previously agreed matters.  His Lordship observed that if this lack of independence was a coincidence, it was a remarkable coincidence and sanctioned the Claimant in costs (although several other criticisms were made which also justified indemnity costs).  The court also took time to reiterate the importance of experts understanding their role and duties, stating at [237]—

“The principles that govern expert evidence must be carefully adhered to, both by the experts themselves, and the legal advisers who instruct them. If experts are unaware of these principles, they must have them explained to them by their instructing solicitors. This applies regardless of the amounts in stake in any particular case, and is a foundation stone of expert evidence. There is a lengthy practice direction to CPR part 35, practice direction 35. Every expert should read it.”

The Senior Master’s decision

Returning to Andrews, Senior Master Fontaine unsurprisingly found that Dr Gibson’s approach strongly suggested that he regarded himself as an advocate for the Claimants rather than as an independent expert whose primary obligation is to the court.  Having considered the above authorities and reviewed some of the most serious transgressions by both expert and solicitors, she concluded—

“…the court has no confidence in Dr Gibson’s ability to act in accordance with his obligations as an expert witness.  The basis upon which the Claimants received permission to rely upon Dr Gibson as an expert witness, namely his duties under CPR 35.3, 35PD paras. 2.1 and 2.2, has been undermined. Accordingly I consider that it is appropriate, and not disproportionate, to revoke the Claimants’ permission to rely on his evidence.”

The Claimants were slightly fortunate that (despite the passage of time since issue) the proceedings were still at an early stage and no trial date had been set.  The court, taking this into account with the fact that non-monetary remedies were sought by the Claimants alongside damages, concluded that a claim against their solicitors would not adequately compensate them and granted permission for a new expert to be relied upon.  The Claimants were not therefore left entirely in the lurch but the attendant costs from the delay and new instructions will of course be theirs to bear and are perhaps a matter between them and their (possibly now former) solicitors.

Advice for TCC practitioners

Each of these cases, including Andrews, has had to reiterate the ‘first duty’ of an expert expounded by Lord Wilberforce in Whitehouse  v Jordan [1981] 1 WLR 246 at 256—

“Expert evidence presented to the court should be, and should be seen to be, the independent product of the expert uninfluenced as to form or content by the exigencies of litigation.”

A view endorsed by Cresswell J in that judge’s classic exposition of the role and duties of an expert in The Ikarian Reefer [1993] 2 Lloyd’s Rep. 68 and now adopted into the wording of PD 35.2.1.

No matter how many times this issue appears before the court, it seems that it is always worth reiterating those words and this case shows, if it needed stating, that it is not in anyone’s interests to have an expert that is not, or does not appear to be, independent.  It is easy for lay clients in particular to be pleased by an expert that ‘fights their corner’.  However, an expert that is too keen to please their paymaster or too willing to reject the other side’s evidence will, at best, be considered by the court as lacking credibility and, at worst, be dishonourably discharged from their role leaving the client without an expert and/or a very large bill and a very large delay.  Therefore, whilst it is of course the expert’s responsibility to understand their own duties and the importance of giving an independent opinion, it is also incumbent upon legal representatives to make sure the expert maintains independence, and is seen to be maintaining independence, because it will ultimately be the client that loses out.

As is noted above, cases in the TCC will invariably involve expert evidence, often across multiple disciplines.  It is therefore particularly vital that practitioners in this area understand the role and duties of both expert and lawyer.  The TCC guide together with CPR Part 35 and the Practice Direction all provide very clear parameters for the interaction between legal representatives and experts.  The Civil Justice Council guidance is also extremely useful in emphasising these.  All envisage some form of discussion regarding expert evidence and it is not uncommon for an expert to be asked to address a particular issue that has perhaps been overlooked in a report, or to clarify a certain conclusion to ensure it is comprehensible and accurately stated, provided always that there is no risk that the expert is not still giving their own independent opinion.  There is also a difference between the production of an initial report and the joint statement, on which it is only appropriate for legal representatives to intervene in very narrow circumstances.  This is because the joint statement has to be the work of the experts together and, whilst an initial report must be independent, it may bind the parties in a way which a joint statement does not (unless they expressly agree to be so bound).  Should any intervention be required, then it must necessarily be done in open correspondence with all parties and experts.

In walking the line between legitimate and illegitimate interference with expert evidence, Lord Wilberforce’s words and the principles set out by Cresswell J ought to be at the forefront of any litigator’s mind.  If in doubt about whether to intervene, try applying the ‘red face test’ (once described to me in a professional ethics class during the bar course): would you be able to justify your actions before the regulator, or in this case the court, without blushing?   Another way to consider your conduct is simply to ask what your response would be if you discovered the other side doing what you are proposing to do? If the answer would be robustly critical – then don’t do it. If you are still in doubt, leave the expert well alone!

James Culverwell is a member of the Lamb Chambers Construction and Technology team.


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