The role of the expert witness and importantly when is an expert not an expert?

The objective of an expert witness is to provide their independent opinion on matters in relation to their field of specialism and, where necessary, explain the area of specialism to the court. Recent cases have highlighted that the expert must take great care not to deviate or stray outside of their field of specialism. 

An expert witness can be of use in mediation, arbitration or negotiations prior to court proceedings as well as in a trial situation. A comprehensive, well written report from an expert witness with a well presented legal case can stave off court proceedings saving parties significant costs in the long run. However, even with the best intentions in the world some disputes will always run full distance as our forensic accounting partner, Fiona Hotston Moore found last summer when appearing in the High Court for cross examination on two separate commercial disputes.

When is an expert not an expert?

The expert must be able to stand on their own two feet!

Saul Haydon Rowe was the expert prosecution witness on trading for the Serious Fraud Office in the Libor rigging scandal. Mr Rowe has recently admitted texting a friend for help in relation to his expert witness role. Mr Rowe also failed to disclose the messages in previous Libor trials. The lawyer for Mr Reich (who was acquitted of conspiracy to defraud) said to Mr Rowe “You have misrepresented your expertise to the SFO and to the juries”, which the expert witness denied. The implications of such failings in the expert witness can be wide reaching and massively damaging to a case. The previously convicted trader, Tom Hayes, currently plans to challenge the expert witness in the Libor conviction appeal.

The expert must avoid bias in their use of evidence

A UK judge has strongly criticised an expert witness in a personal injury case, accusing him of misusing the works of others, misrepresenting his critics, and abandoning any claim to objectivity.
Judge John Griffith Williams, recorder of Cardiff, sitting as a High Court judge, said that Peter Behan, Professor Emeritus of Neurology at the University of Glasgow, “demonstrated a capacity to use his interpretation of the evidence to suit his purposes which conflicts with his duty to the court as an expert witness.”

The expert must conduct conflict checks and disclose any connection to either party

In EXP v Barker [2017] EWCA Civ 63 the Court of Appeal upheld the trial judge’s rejection of the evidence of an expert witness.

The Upper Tribunal Judge commented “The starting point is to identify what the judge decided. He considered that the witness had so compromised his approach that the decision to admit his evidence was finely balanced, and that the weight to be accorded to his views must be considerably diminished. In my view he was fully entitled to take that view. Indeed, had he decided to exclude Dr Molyneux’s evidence entirely, it would in my view have been a proper decision. Our adversarial system depends heavily on the independence of expert witnesses, on the primacy of their duty to the Court over any other loyalty or obligation, and on the rigour with which experts make known any associations or loyalties which might give rise to a conflict. Dr Molyneux failed to do so here, despite an express direction to that effect. Indeed, the omission of mention of papers co-authored with Dr Barker points in the other direction.”

Ensors have always taken the role of the expert witness seriously and our specialist team led by partner Fiona Hotston Moore, also an Accredited Counter Fraud Specialist, includes only experienced individuals who have undergone the appropriate training. Our training includes membership to The Academy of Experts which provides accreditation of expert witnesses and our membership to the Network of Independent Forensic Accountants (NIFA).

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