Expert evidence can make or break a party's case at trial. Andrew Jones and Joe Bryant look at three recent Court decisions where the parties got it wrong and consider the risks to solicitors acting in litigation regarding expert evidence.

Experts have an unusual dual role in litigation, in that they owe:

  • A duty of care to their instructing party. This is a duty to provide expert opinion within a reasonable range; and
  • A duty to the Court to provide objective, unbiased, impartial and independent evidence. This duty overrides the above duty to their instructing party. Experts should follow the requirements set out in Part 35 of the Civil procedure Rules and the Civil Justice Council's "Guidance for the instruction of experts in civil claims".

Three recent decisions of the Court show the potentially catastrophic consequences of experts and the parties getting it wrong.

Essex County Council v UBB Waste (2020)1

In this case, the Council entered into a 25 year £800m contract with UBB for the design, construction and operation of a biological waste treatment facility to process household waste.

The Council sought to terminate the contract on the grounds the waste treatment facility failed various tests. UBB denied any default and alleged any problem was due to the composition of the waste provided by the Council. The Court found that UBB made a number of serious design errors and found in favour of the Council (see our general update on this case here)

UBB relied upon one expert on all the design and technical issues. The Judge found that there were "obvious and serious conflicts of interest" in UBB's expert's evidence, given:

  • The expert and his company had in fact been retained by UBB on the project and had extensive involvement in the design of the facility. The expert was therefore effectively giving expert evidence on his own designs;
  • UBB's sister company had previously served a preaction letter on the expert's company alleging its designs were negligent;
  • The expert requested that UBB withdraw its potential claim against his company before agreeing to provide expert evidence. Full assurance against future claims was not given and it was therefore in the expert's interests for his instructing party, UBB, to defeat the Council's claim; and
  • The Judge went on to find that the expert also failed to distinguish between advocating for UBB and providing independent opinion when giving his evidence.

Whilst the Judge declined to exclude the expert's evidence altogether as inadmissible, the Judge stated he treated it with caution, and it can be seen generally preferred the evidence of the other experts.

De Sena v Notaro (2020)2

Whilst one party felt the wrath of the Court in Essex County Council, it was both parties and their lawyers in the firing line in De Sena. The claim involved the demerger of a family business between two brothers, with the allegation that one had procured the demerger by undue influence on the other. There was also a claim against the accountants who had been retained to act on the demerger. Both parties relied upon expert accountancy evidence on demergers.

The Judge found:

  • Neither expert accountant had sufficient expertise in advising on demergers. The Judge criticised the parties for assuming that, because accountants regularly advise clients on demergers, therefore any accountant, whether he has the experience of advising clients on demergers or not, is qualified as an expert witness in this field; and
  • The questions posed to the experts for their reports by their instructing solicitors were largely irrelevant or questions of law or fact for the Court and not the experts to decide. Indeed, the Judge described one question as "one of the most egregious and naked usurpation of the functions of the court that I have ever seen" and said he had "never before seen such an extraordinary set of questions" put to an expert witness.

The Court therefore went one further than in Essex County Council and disregarded both parties' expert reports in full.

A Company v X, Y and Z (2020)3

The anonymisation of the parties in this case reflected that it involved two ongoing confidential arbitrations of disputes relating to delays in the construction of a petrochemical plant. The claimant was the developer who had retained both a contractor to construct the works and a third party to issue construction drawings and supervise the contractor. The defendants were an international group of companies which provided various expert services.

The contractor commenced arbitration against the claimant for additional sums allegedly due arising out of delays to its works caused by the claimant, which included the late issue of certain drawings. The claimant argued that if it were responsible to the contactor for any delays caused by the late issue of drawings, it would pass on liability to the third party who issued the drawings. The claimant retained "K" of one of the defendant group of companies for expert advice in the arbitration.

A few months later, the third party in question also commenced arbitration proceedings against the claimant for sums owing. The claimant counterclaimed for delays caused by the third party. The third party sought to retain "M" of one of the other defendant group of companies for expert advice.

The Court found that:

  • Experts owe their instructing party a fiduciary duty of loyalty, which went beyond the individual expert to also include their company or group of companies; and
  • The two arbitrations concerned the same delays and there was a significant overlap in the issues. There was therefore plainly a conflict of interest for the defendants in acting for the claimant in the first arbitration and against the claimant in the second arbitration, in breach of their fiduciary duty of loyalty.

The Court therefore granted an injunction against the defendants acting for the third party in the second arbitration.

Risks to solicitors with expert evidence

Since Jones v Kaney (2011), experts no longer benefit from immunity from suit and there have been a number of claims against experts for breaching their duties owed to their instructing parties

However, it is not just the expert who may be in the firing line in the event of problems with expert evidence. The solicitors involved in the three cases above may well have been sitting uncomfortably as the expert's evidence unravelled. Solicitors have a duty to act with reasonable skill and case in handling litigation, which includes in relation to evidence. Solicitors generally have conduct of identifying suitable experts, instructing them, asking the relevant questions for the expert's reports and "directing" the expert throughout the litigation. And so if they get it wrong and the case unravels because of a poor choice of expert, the solicitors can expect to find themselves firmly in their disgruntled client's sights.

There may be various reasons why clients may wish to pursue a negligence claim against their solicitors instead of the expert if litigation goes wrong. The failings may be more identifiable as those of the solicitor, such as failings in the questions asked to the expert in the solicitor's instructions or failing to appreciate that the expert may not be seen as having sufficient expertise (even if the expert has acted as best they could as in De Sena). Further, given negligence claims against experts are still a relatively new concept, there is a more established body of caselaw for claims against solicitors than experts. Solicitors may also be seen to have deeper pockets and better PI insurance cover.

If a party's expert evidence ends up being criticised or found inadmissible, it could leave that party with tainted or even no witness evidence to rely upon at trial and with no opportunity to obtain better alternative evidence instead – as happened in the Essex County Council and De Sena cases. If this is a result of negligence of the instructing solicitor, the losses that parties could claim from the solicitor as a result may include:

  • The wasted costs of the expert evidence, particularly if it is found inadmissible (as in De Sena) or in conflict of interest (as in A Company v X, Y and Z) and cannot be used at all; and
  • The lost chance of obtaining a better result at trial had the client had the benefit of satisfactory expert evidence.

Dangers for solicitors to avoid

Solicitors therefore need to think very carefully when identifying, instructing and directing experts. There can sometimes be a tendency for solicitors to instruct someone as an expert who:

  1. Is already involved in the project. Parties often do this with a view to saving costs given that person will already have detailed knowledge of the project and should therefore already be "up to speed". This is not uncommon on construction disputes, where a new consultant is appointed to remedy problems caused by a negligent professional, and the claimant may wish to appoint that new consultant as their expert.

    The risk here is that the expert may not be seen as independent and impartial and even in conflict of interests, particularly if there is any criticism of their own work or they otherwise may benefit from their client's case succeeding (as in Essex County Council and A Company v X, Y and Z).

  2. Has proved a worthy expert previously. There is sometimes a risk in such a case of not properly considering whether the expert may have sufficient expertise on the new matter even if they did on the previous matter and, even if they do, failing to properly reiterate the requirements for expert evidence again. The lack of the expert's expertise in De Sena resulted in the party being unable to rely on any expert evidence at all.
  3. Has agreed favourable rates with the solicitors and/or is on a panel.
  4. Is a friend or a contract of the solicitor (less common but we have seen this).

Each of the above scenarios carry dangers, both in terms of the expert's evidence ultimately being up to scratch and acceptable to a Court, and also in terms of opening up the solicitor to criticism over the underlying motives for their expert selection which could taint their client's case and provide grounds for a subsequent negligence claim.

The outcomes in the three cases discussed above should be a salutary reminder of the need to be fully objective when identifying and instructing experts on cases, including properly considering potential conflicts and sufficient expertise. Whilst it is good to have costs in mind, first and foremost the expert needs to have the necessary expertise and the appointment stand up to scrutiny. If solicitors are having difficulty finding a suitable expert that fits the necessary expertise/budget, or the client wishes to instruct someone who the solicitor has concerns about, then the solicitor should advise their client accordingly and document that advice to minimise the risk of later claims if there are subsequently problems with that expert evidence.


1 Essex County Council v UBB Waste (Essex) Limited (2020) EWHC 1581 (TCC)

2 De Sena & Anor v Notaro & Ors [2020] EWHC 1031 (Ch)

3 A Company v X, Y and Z (2020) EWHC 809 (TCC)

Originally published 03 August, 2020

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.