Challenging the expert's qualifications, methods or impartiality or attacking the facts on which he claims his conclusions are based are among the tactics employed by counsel on the opposing side, Mr Garrett Cooney SC, told the conference.
The cross-examination of an expert was one of the most difficult tasks undertaken by counsel, he said, and required careful and detailed preparation.
This should include close consultation with the barrister's own experts and a study of the relevant literature, so that he or she became an "expert" for the duration of the case.
When carrying out the cross-examination, counsel could probe the data on which the expert's opinion was based in the hope of establishing that some of it was defective, or challenge the expert's methods by showing that other tests could have been carried out which would have produced a different result.
"It may also be possible to demonstrate that the progression from fact to opinion is flawed or illogical," he said.
Challenging the witness's impartiality was a frequently used tactic, but rarely in the form of a full frontal assault, he said.
"An insinuation of bias or impartiality will usually be broached in the most oblique manner, thus enabling counsel quietly to back-pedal away without too much loss of face if he encounters a convincing rebuttal to such a suggestion."
He said a judge "may be more receptive to a suggestion of bias on the basis that the expert's services are exclusively or regularly availed of by one client, such as an insurance company, or by one category of clients, such as plaintiffs who complain of chronic pain for which there is no apparent organic explanation."