Preparing for a hot tub

Hot-tubbing, the process of expert witnesses from the same discipline providing concurrent expert evidence (as set out in paragraph 11 of the CPR practice Direction 35), is becoming more widely used. Dr Chris Danbury, Consultant Intensive Care Physician has been instructed in cases reaching the High Court, Court of Protection, Coroner’s Court, Court of Appeal and Supreme Court. In this article he shares his experience of “hot-tubbing” and how expert witnesses can best prepare, and be prepared, for a judge-led joint examination.

Expecting the unexpected

For many expert witnesses the courtroom is not a familiar environment. Any expert worth their salt will have attended training in courtroom skills, with the focus historically on giving their testimony confidently and clearly under cross-examination. It can then be daunting to arrive at court to be told that the judge has given direction for ‘concurrent expert evidence’ or a ‘hot tub’. On the face of it, it doesn’t change the preparation an expert witness should and would do, although a thorough knowledge of current reviews and meta-analysis on the specific topic in hand will stand an expert in good stead in a ‘hot tub’. For legal counsel any forewarning gives a first-timer the opportunity to read up about the process and how it should work (recognising that as a ‘judge-led’ approach, it will vary from individual to individual). Some judges have a history of ‘hot tubbing’ and legal counsel could usefully identify that to an expert who is preparing for court.

Striking the right balance

When ‘hot tubbing’ works well it provokes intellectual debate between experts. It is a good way to explore complex issues and seek to find common ground in the areas where two experts are not in agreement. From an expert’s perspective, there is a balance to be struck between confidence in one’s own opinion and having an open mind and being flexible if the other expert makes a valid point. A mutual respect between experts is key to the success of the ‘hot tubbing’ format, so an expert witness should not be deferential to a colleague who may be seen to be more senior.

A more junior expert should keep in mind that their view is still relevant, possibly more so if their clinical work is more extensive at the current time than their senior counterpart. Experts with experience, age and/or seniority on their side should not seek to undermine the other expert on that basis.

Staying on topic

The less structured and less formal setting of a judge-led joint examination can allow an expert witness to stray off topic. Legal counsel could usefully help experts prepare for hot-tubbing by reminding them of the scope of their evidence and that their duty is to the court and not as advocates for their instructing party.

With increasing focus on the length (and cost) of trials, the ‘hot tub’ looks like it is here to stay. For expert witnesses this means that court room skills need to be extended to prepare them for questioning, and being questioned by, the other expert as well as communicating clearly and effectively with the judge. The first time in the ‘hot tub’ doesn’t need to get an expert witness hot under the collar with a little support and forewarning from their legal counsel.