The use of single joint experts could render the judge purely a “figure head” in proceedings, the president of the Supreme Court has warned.
Delivering the keynote address at the Bond Solon expert witness conference on Friday, Lord Neuberger questioned whether the present system of cross-examination of experts is the best way to proceed.
“It can be fun for the advocates and good theatre, but is artificial and gladiatorial and not the best way of getting to the truth,” he said.
But at the same time he said he was “nervous” about the idea of having a single joint expert.
Where the expert’s opinion evidence is not tested by cross-examination, he said, the expert may be tempted to “over-egg” their evidence.
Lord Neuberger described the notion of a dispassionate disinterested expert as a “myth”. Experts will naturally be biased, through commitment to particular theories or principles, or because they are being paid by one party. Where you have a party-appointed expert, he said, you can test where any bias may be.
A joint single expert, he said, has the advantage over a party appointed one in that they are less likely to be biased in favour of the client, but any bias will be “hidden” and it will be hard to “tease out” without cross-examination.
He added: “I worry that if you have a single joint expert, their evidence is normally the decision that decides the case. Is the judge just a figure head who adopts what the expert says?”
Lord Neuberger accepted that in cases where “not much is at stake” and where the expert evidence goes to a small issue, proportionality would justify a joint expert.
However, he indicated that ‘hot-tubbing’ – where lawyers and experts discuss the evidence round a table – might be better in other cases.
But he said it would be wrong to form a view until there is more evidence about the merit of the two systems.
Elsewhere in his speech, Lord Neuberger warned of the dangers of lawyers, judges and the general public not understanding statistical evidence and therefore not treating such evidence appropriately.
“One problem of the modern age is the unsatisfactory way figures are used and understood by the majority of people,” he said.
Statistical evidence can be “powerful and conclusive”, but he warned that it can also be “full of pitfalls”. Figures that have a “beguiling attraction” can be misleading.
The failure to understand figures was at the root of the problem in the case involving Professor Sir Roy Meadows who gave evidence in the case of Sally Clarke – the solicitor whose conviction for murdering two of her children was eventually overturned after his evidence about the unlikelihood of two cot deaths occurring in the same family was discredited.
Judges and arbitrators can be “too impressed” and “give too much respectability” to figures, Lord Neuberger said. All practitioners and judges need to understand statistical evidence better than they do.