A plunge into the hot tub: Civil Justice Council report on concurrent expert evidence

One of the lesser discussed aspects of the Jackson reforms was the formal introduction of concurrent expert evidence, aka “hot-tubbing“, as an optional procedure to be adopted at the discretion of the court. As described in PD 35.11, it involves hearing evidence concurrently from the experts in a particular discipline, with the judge initiating the questioning and discussion, rather than having each expert give evidence and be cross-examined separately in the usual way.

In his November 2011 lecture, Focusing Expert Evidence and Controlling Costs, Lord Justice Jackson reported that the general view in Australia (where hot-tubbing originated) was that the technique was beneficial for a number of reasons. These can broadly be summarised as saving time, saving costs, improving the quality of the expert evidence and assisting the court’s understanding of the expert evidence.

But despite these proclaimed benefits, since the formal introduction of hot-tubbing into English civil procedure in April 2013, the general perception is that this “additional tool” in the court’s armoury has rarely been dusted off for use.

Civil Justice Council review

Prompted in part by the perceived reluctance of English judges and practitioners to use hot-tubbing, it was decided that this should form the first topic for consideration by the Civil Justice Council’s “Civil Litigation Review Working Group”.

Chaired by Professor Rachael Mulheron of Queen Mary University of London, and with myself as deputy chair, the group was set up in May this year to consider and review a series of discrete topics relating to civil litigation. Its work will ultimately feed into the MoJ’s Post‐Implementation Review of the Jackson reforms, which is due in early 2018.

Through various sources, including surveys distributed to the judiciary, legal practitioners and expert witnesses, and discussions with judges and others who had experienced hot-tubbing in practice, the working group sought to understand how and why hot-tubbing was (or was not) being used in courtrooms in England and Wales, whether it was achieving its anticipated benefits, and whether anything should be done to improve general familiarity with and understanding of the technique. The working group’s report was published today.

A patchwork quilt

One point that quickly became apparent to the working group was that, in practice, there is not just one procedure by which expert evidence may be given concurrently, as PD 35.11 might appear to suggest (though the PD does recognise the judge’s discretion to modify the procedure identified). There are, in fact, a number of variations.

Here the terminology becomes somewhat awkward, as the working group discovered, particularly as the term “hot-tubbing” itself is by no means well-loved (either here or in Australia). The working group has suggested “judge-led joint examination of experts”, or JJEE, as an alternative label. I will use the two interchangeably.

But in addition to this process, in which the discussion is very much judge-led, the working group also identified a distinct process, which it has termed “sequential ‘back to back’ evidence”, in which all experts give evidence on each issue in turn. This is a form of concurrent evidence, as the experts are sworn in concurrently, but it is not judge-led in the way hot-tubbing is. The advocates for the parties take on a more traditional role, with each expert giving evidence and being cross-examined on the first issue, and then repeating the process for the second issue, and so forth.

There are also various hybrid versions, in which judge-led questioning and more traditional cross-examination may be combined, either generally or by reference to particular topics.

The working group has not sought to impose uniformity on this “patchwork quilt” of techniques, recognising that it is important for the court, and the parties, to be able to adapt the procedure depending on the needs of the individual case. However, the working group took the view that it would be helpful to recognise this flexibility by indicating in PD 35.11 the variety of techniques that may be used. To this end, the report sets out a suggested re-draft of the PD, which the Civil Procedure Rule Committee (CPRC) is invited to consider.

When hot-tubbing (or JJEE) is appropriate

The working group also considered that it would be helpful to supplement the PD with further guidance for judges and practitioners on various issues, including the factors which might indicate that JJEE is (or is not) appropriate.

Again, the aim of the working group was not to be prescriptive, but merely to identify factors which might assist the court in determining whether or not a case is suitable. The starting point in the proposed new guidance note is that there is no restriction on the type of case, or the nature of expert evidence, for which the court may direct hot-tubbing. However, there are various factors which ought to be taken into account, relating to both the nature of the expert evidence and the logistics of the process. I won’t try to identify all the factors here, but in my view a few points particularly stand out.

Firstly, since JJEE requires the judge to take the lead role in questioning the expert witnesses, it is essential that he or she is sufficiently on top of the relevant issues to be able to perform that role effectively. If the judge is not sufficiently comfortable with the relevant field of expertise, or does not have sufficient preparation time, difficulties may arise.

Secondly, any sort of imbalance between the experts is a significant factor, whether in terms of the number of experts (eg a single claimant, with one expert, facing a number of defendants, each with their own experts supporting broadly the same position), or their seniority or expertise. The feedback to the working group did not suggest that such an imbalance should necessarily preclude a direction for hot-tubbing, but it is clearly something that would need to be carefully managed.

Thirdly, if one party wants to challenge the opposing expert’s credibility, whether on the basis of a lack of independence, necessary qualifications, expertise and/or experience, it is clear that the hot-tub is not the appropriate place for that to happen. Again, this need not preclude hot-tubbing entirely, depending perhaps on the nature and extent of the challenge. The judge may, if he or she considers it appropriate, make some sort of hybrid order, so that the challenge to credibility will proceed via traditional cross-examination and other issues via JJEE.

Procedural fairness

Another issue addressed by the working party was the need to ensure that a direction for hot-tubbing, and the procedure actually adopted, does not have a negative impact on the procedural fairness of the hearing.

Crucially, from the perspective of parties and their legal representatives, this includes the need to ensure that each party has a sufficient opportunity to test the experts’ views. Concerns about potentially being shut out from that opportunity appear to underlie a reluctance on the part of some practitioners to adopt hot-tubbing. The working group’s report states (at page 50):

“Given the importance of this procedural issue in deciding the outcome of the substantive merits of the litigation, the Working Group considered that it may be useful for a court to at least consider whether it would be desirable to invite counsel to ask questions at the conclusion of the judge-led questioning on each topic, rather than at the overall conclusion of the hot-tubbing session. That may reduce the risk of the parties’ feeling that the opportunity to test points had not been properly provided.”

This issue is addressed in the proposed new guidance note for judges and practitioners, together with other aspects of procedural fairness, including whether each expert has been afforded an equivalent opportunity to address the issues, the order in which the experts are given the opportunity to answer questions, and so forth.

Communication to the experts

The working group also identified the need to ensure the expert witness is kept in the loop about the process to be adopted at trial. The proposed new guidance note for judges and practitioners includes a statement that, when a direction for hot-tubbing is made, a copy of the relevant order should be served on the relevant experts forthwith for their information.

To ensure the experts know what to expect from the process, the working group also recommends that, at the same time as the order is served on the experts, they should be provided with a short information note explaining the hot-tubbing process and how it differs from the traditional manner of giving expert evidence at trial. The working group report contains a suggested draft of the information note.

Raising awareness

As well as the suggested amendments to the PD, the new guidance note for judges and practitioners, and the information note for expert witnesses, the working group report recommends a number of other measures to enhance familiarity with hot-tubbing amongst the judiciary and practitioners, and to encourage its use in appropriate cases. In particular:

  • A training video demonstrating the process of hot-tubbing, which could be disseminated as part of the training activities being undertaken by the Judicial College in this area, and a potential training video for expert witnesses.
  • Inserting a further question in the Directions Questionnaire, the Listing Questionnaire and the Case Management Information Sheet to flag up the possibility of expert evidence being given concurrently.
  • Addressing unnecessary variations in how the process of hot-tubbing is described in the various Court Guides, ideally by replacing divergent descriptions with cross-references to the PD and the guidance note (if adopted).

Achieving its aims?

As noted above, Lord Justice Jackson identified four key objectives for concurrent expert evidence: saving time, saving costs, improving the quality of expert evidence and assisting the court’s understanding of the expert evidence. How well is hot-tubbing achieving those aims?

It seems reasonably clear that, where it is used, hot-tubbing can save significant amounts of time at trial, though obviously this time saving may not be achieved where it is combined with substantial cross-examination (using a “hybrid” approach discussed earlier). And any saving of trial time may, from the perspective of judicial resourcing, be offset by increased judicial preparation time.

Perhaps surprisingly, however, the majority of respondents to all three surveys (judiciary, legal practitioners and expert witnesses) did not consider that hot-tubbing had led to a saving of costs for the parties. It is not clear why that might be the case, particularly given the majority view that time at trial was saved. The working group report suggests that, given this counter-intuitive result, some further exploration may be warranted in future to understand the reasons for this perception and address the concerns.

The feedback during the project did, however, suggest strong support for the notion that concurrent evidence improves the quality of the expert evidence and assists the court’s understanding of it, with the vast majority of judiciary and legal practitioners who responded to the surveys expressing positive views on these aspects. Expert witnesses who responded were slightly less uniform in their views, but the majority were still positive.

So in summary, based on feedback to the working group, it appears that hot-tubbing can have significant benefits in terms of saving trial time and enhancing the quality and understanding of the expert evidence, though the jury is still out on its potential for overall costs savings.

Next steps

Now that the working group’s report has been published, it will be for the CPRC to decide whether the proposed amendments to PD 35.11 should be taken forward and in precisely what form. The other recommendations, including the guidance note for judges and practitioners and the information note for experts, will follow on from that activity. It is hoped that the CPRC may find time in its schedule to address these issues soon after the summer holiday period.

Herbert Smith Freehills Maura McIntosh

Leave a Reply

Your email address will not be published. Required fields are marked *

Share this post on: