It is an occupational certainty that expert witnesses will be challenged robustly in cross-examination; how the expert deals with that challenge will be revealing and will be commented on by the judge.
How should an expert respond to criticism, challenge, and adverse comment?
This article looks at the experience of two experts, Dr. E and Mr. T, in two very different cases. Both experts dealt with the challenge appropriately and their approaches are worth evaluating.
Expert Witness: Dr. E
Dr. E is a retired consultant paediatrician who was instructed by the prosecution in the recent murder trial of Lucy Letby.
During his cross examination, two paths were followed in order to try to undermine his credibility and reliability: the way in which he had become involved in the prosecution case and previous criticism of him by a judge in another case.
It was put to him, and Dr. E accepted, that he had contacted the National Crime Agency when he became aware that Cheshire police were investigating the infant mortality rate at the Countess of Chester Hospital, saying that he had expertise in neonatal cases and would be interested to help.
The defence accused him of “touting” for the role of expert witness for the prosecution.
In evidence, he stated that he was simply offering his professional opinion to the police should they need it. He said that he was fully independent and impartial, that he knew his duty to the court and was fulfilling that duty. When challenged that he had adopted a partisan approach, he went further by saying:
“I’m completely independent. I have been giving evidence in court for a long time. I know about impartiality. I know about the rules. I’m not here for the prosecution. I’m not here for the defence. I’m here for the court.”
He was also faced with the comments of a judge in the Court of Appeal in an unrelated case, who had criticised Dr. E for producing a report which the judge described as not providing a “balanced opinion”.
The defence used the above issues to argue that the judge should exclude Dr. E’s evidence from the jury on the grounds that he failed to act appropriately, with independence, impartiality and objectivity.
The trial judge, Mr. Justice Goss, rejected that argument, on the basis that it was for the jury to consider the issue of Dr. E’s reliability by reference to all the evidence in the case.
Dr. E clearly did not accept that challenge made by the defence and stood by his assertion of independence. Although we will never know how the jury arrived at their decision to convict, it is a fair assumption to make that, in doing so, they accepted Dr. E’s evidence and must have found him to be a reliable witness.
Dr. E’s approach? Robust defence.
Expert Witness: Mr. T
Mr. T is another very experienced expert witness. A Chartered Surveyor of many years standing, he had been commended in 2014 by a judge in the Central Family Court for approaching a complex valuation with the “required degree of expertise and independence” expected of an expert witness.
In 2019, he was criticised in the Upper Tribunal (Lands Chamber) for not having inspected the objectors’ properties and, therefore, not being able to give a properly evidenced opinion.
He accepted the criticism made by the Deputy President of the Tribunal− that he should have applied to the tribunal when his solicitors refused to allow him the time to inspect the properties. He understood that he should not have allowed his instructing solicitors to limit his ability to fulfil his overriding duty to the court.
His evidence was not given much value by the judge in his judgment.
That was a stinging criticism, but one which Mr. T had to, and quite rightly did, accept. Mr. T went further when writing his next report for a new and unrelated case. He drew the court’s attention to the criticism made in the 2019 case, giving the case reference and the paragraph number in the judgment. He openly admitted where he had been at fault and went on to describe how he had gone back to the expression of the duty to the court in CPR35. He also made sure, in the instant case, that he was properly complying with his duty to the court.
Result? The Tribunal in the second case found him to be a credible, reliable witness with whom they agreed.
Mr. T’s approach? Transparent admission of fault.
What can expert witnesses learn?
There should never be any substitute for honesty and integrity. An expert must know the scope of their role and their duty and be able to express and demonstrate that they are fulfilling it at all times in their work as experts.
Criticism and challenge will come.
If it is well founded (i.e. if the expert has erred or not done something which they should have done), the expert must immediately accept that and not try to defend the indefensible. The longer they fight the point, the more their credibility will be destroyed.
This applies to future cases too. If the expert is proactive and transparent about any past errors, the scope for further cross-examination will be reduced. For example, in Mr. T’s case, he was cross examined about the error in the previous case – until the judge intervened and told the barrister to move on.
The expert should then go on to demonstrate what they have done to correct past mistakes and how they have guarded against a repetition in the future.
If the criticisms are not well founded, then the expert should say so. This is not about admitting fault where there is none.
Conclusion
Bond Solon urges experts in all disciplines to make themselves fully aware of their role and their duty under the rules of court. The duty to help the court and to be independent applies in all the UK jurisdictions whether through case law or through the rules of court in England and Wales. An expert witness must read, understand the rules and apply them.
Bond Solon’s expert witness courses always reference the duty of the expert. The trainers are ready to discuss the application of that duty and the challenges that the expert will face as they seek to do so.
In reflecting on his experiences, Mr. T was well aware that whilst he had taken fifty years to build his reputation, that reputation could be destroyed in less than 50 seconds.
Author: Nicholas Deal
This article was first published on 29 September 2023