Improving concurrent expert evidence in the English courts

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Hot-tubbing – Concurrent Expert Evidence

Concurrent expert evidence is said to save time, save costs, improve the quality of the expert evidence and assist the court’s understanding of the expert evidence.  On 1 August 2016 the Civil Justice Council published a study by its new Civil Litigation Review Working Group on how the process of concurrent expert evidence was operating in English courtrooms and whether the overall aims were being achieved three years after the Jackson Review introduced this technique into CPR.

Their findings are based on a survey of about 100 instructing solicitors and barristers, judges and experts across a wide range of courts and types of case. The largest case considered was Streetmap.EU v Google.

The study shows there is a wide variation in how the technique is being used as well and that it is still being used insufficiently.  There are wide differences in:

  • How Judges questioned experts – in some cases judges set the agenda and the same questions were not put to each expert
  • Experts interact – for example the second expert was invited to comment but without dialogue
  • Which expert is questioned first (one described the approach as “shambolic”)?
  • Testing the expert’s opinion – should Counsel be invite to do so at the end of each question?
  • The layout of the courtroom – in one example the experts had to twist their chairs round for each question
  • Whether opening statements by experts are allowed

The study concluded that these variations should be addressed by further codification in a revised PD35.11, separate new guidance notes for practitioners and judges, an information note for experts and further training for judges.  In view of the wide variation in approaches, the working group suggested that the technique should be called a “judge-led joint examination of experts”, or JJEE, as an alternative label.

The proposed revision to PD35.11 also introduces the possibility of a “teach-in” for the judge by an independent expert, paid for by the parties, either with counsel present or in private session where the papers would be distributed to the parties afterwards.  This technique used in Electromagnetic Geoservices ASA v Petroleum Geo-Services [2016] EWHC 881 (Pat) (19 April 2016)

It was rewarding to read that one judge described the Joint Statement as “one of the most valuable documents in the case”, emphasising the importance of the document for the judge’s preparations and in view of the amount of careful thought and effort usually put into these documents by experts.

It is proposed to review the Court guides to ensure there is a uniformity of approach, which is not currently the case and to include an additional question in the revising Directions/Listing Questionnaires:  “Do you consider that any part of the oral expert evidence should be given concurrently (see PD35, para 11)?”

The study concluded that concurrent expert evidence may take one of three proposed procedures:

  • Evidence given by judge-led expert examination or JJEE;
  • Evidence given by sequential, back-to-back, examination; or
  • A Hybrid procedure

Appendix B to the Study sets out criteria to help decide whether judge-led examination is appropriate, the types of cases where it may be appropriate, the time for giving direction, informing expert (in one case I was informed on the day of the hearing!) and guidance on achieving procedural fairness

The study repeated the advice given in the original Jackson pilot in Manchester that if there is a “serious challenge” on the competence, independence or credibility of an expert, then JJEE should not be used.

In my experience the technique enhances the position of the expert and the power of a strong personality.  This means that future experts will be chosen, and judged, based on their performance in the “hot-tub”.  I wrote my Institute’s guidance on giving concurrent expert evidence, based on my own experience of the technique in arbitration hearings (click here to read more).

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Charles Lazarevic

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