There have, however, been longstanding concerns raised about the loss of objectivity of some expert witnesses and there has been a spate of cases where expert witnesses have received some harsh judicial criticism.  

Experts must have relevant expertise

Last year in De Sena v Notaro [2020] EWHC 1031, the court disregarded expert accountancy evidence relating to the practice of demerger transactions on the basis the expert witness was a forensic accountant but this did not make him an expert in demerger transactions.

The court held:

“…expertise is acquired by doing the thing in question, usually over many years, and merely being an accountant (or anything else) for a long time does not mean that you become an expert in everything that accountants (or whatever it may be) commonly do.”

Experts must have access to the same available information and must provide unbiased opinion

The importance of ensuring all experts of like disciplines have access to the same material was highlighted by the recent case of Dana UK Axle Ltd v Freudenberg FST [2021] EWHC 1413.  The court excluded the defendant’s technical expert evidence on the seventh day of trial due to ‘serious and unexplained’ breaches of a pre-trial review (PTR) order and breaches of CPR Part 35, PD 35 and the related 2014 Guidance for the Instruction of Experts in Civil Claims (2014 Guidance).

The judge found:-

• The Defendant’s experts were provided with information which was not disclosed in their reports or provided to the Claimant’s experts. The Defendant had freely exchanged information directly (including via videoconference calls) with its experts without oversight by its legal team.
• The experts had carried out various site visits without informing the Claimant’s experts and without any contemporaneous record of the information collected during the visits.
• The experts failed to identify the information they relied on in support of their opinion.
• The experts were influenced by the Defendant’s in-house specialists. In particular, the Defendant’s experts had relayed information from their joint expert meetings with the Claimant’s experts to the Defendant’s in-house specialists and, without any oversight by the Defendant’s legal team, sought the Defendant’s input on how to respond.

These breaches meant the parties’ experts were not operating on the same level playing field and the Defendant’s evidence was excluded in its entirety.

The decision highlights the importance of ensuring there is transparency regarding what information and documentation is provided to expert witnesses. Expert witnesses should ensure that the information which they receive has also been received by their opposite number.

Independence and impartiality is also key; direct contact between experts and client, without solicitor involvement, should always be avoided.    

Comment

The courts are alive to “a worrying trend…of failures by experts generally complying with their duties” (Beattie Passive Norse v Canham Consulting Limited [2021] EWHC 1116).  

Expert witnesses must fully understand and comply with their duties under CPR Part 35. Their independent, objective opinions will be tested while giving oral testimony at trial and their evidence may be disregarded if they are have insufficient expertise, or if they are perceived as simply a mouthpiece for those instructing them, or where the experts have not been operating on a level playing field because they have received different materials.

Expert witnesses may be exposed to negligence claims if their credibility is undermined. Also non-compliance with CPR Part 35 runs the risk of an adverse costs order being awarded against the offending party.  The best advice is: fully comply with the rules. If an expert has any concerns about conflicts of interest or that the matter is beyond their expertise, then they must raise these concerns with those instructing them at the earliest opportunity and, if appropriate, decline the instruction.