“Hot-tubbing” experts reduce cost of civil litigation and ensure objectivity

One of the speakers at the recent Expert Witness Forum in Toronto, Dr. Ruth M. Corbin, referred me to a detailed description of the “hot-tub” method of dispute resolution that she had written. (Ref. 1, see also 2)  “Hot-tubbing” is legal jargon for a concurrent expert evidence process, and apt jargon at that.  Experts for all parties to a dispute get together in a court room and talk it out.  The method reduces court time and civil litigation costs involving experts, and increases objectivity.

Australia, where it originated, New Zealand, Britain and Canada are relying on the process more and more.  Other countries are taking an interest.  Adversarial America?  Not so much.

The method involves experts, with their individual forensic reports for different parties, meeting together in court before a judge and agreeing on a single expert report on the problem.  There is also a variant of the “hot-tub” process suited to other forms of dispute resolution outside a court.  This would be like a pre-trial conference and is usually in the absence of lawyers.

Seeing as more than 90% of disputes are settled out of court, and close to 100% for some types of problems, there is lots of opportunity for this method to resolve disputes.  Interest in a variant of “hot-tubing” is certain to increase in light of the Jordan decision by the Supreme Court of Canada last year.  The decision will further delay the hearing of civil litigation cases in court, at least in the short term.

To me, “hot-tubbing” is little more than a consensus-building process.  Experts do their individual forensic investigations, analyse the data, draw conclusions and formulate an opinion.  They then sit down together, peer review each other’s work, discuss the issues and reach a consensus on the cause of the problem.  Expert’s just want to solve the problem, explain the issues in simple language and get onto the next problem, particularly technical experts.  Most of us are not adversarial by nature, nor hired guns by a long shot.

Ruth’s paper is a good read in plain English with practical descriptions and examples of “hot-tubbing” in action.  The guidance and comment in her paper gets you almost to the point where you just might be able to do it yourself.  If not enough guidance, you can review any number of the 73 references and citations Ruth includes in her paper.

The “hot-tub” method is well developed in relying on the consensus building nature of experts.  But it’s not perfect as Ruth points out in three different ways.  One embarrassing defect is that development of the “hot-tub” method – to reconcile differences among experts – had little input from experts!

I can’t help but wonder if the cause of some of the civil litigation that is being resolved by “hot-tubbing” is because experts were not involved in the merit assessment stage of the cases, another embarrassment.  We get retained months or years after a case is taken and after the cost of the technical expert’s work is estimated by a non-technical person.

The omission of input by experts in development of the “hot-tub” method is recognized by people like Ruth M. Corbin and will be corrected over time.  Possibly this will be reflected at the merit assessment stage of a case and further reduce the load on the court system.

(Some of the comment in the above is taken from Dr. Corbin’s paper)


  1. Corbin, Ruth M., The Hot-tub Alternative to Adversarial Expert Evidence, The Advocates Journal, Spring, 2014 (Dr. Corbin is Chair, Corbin Partners Inc., Ontario)
  2. Biased experts cured with a soak in the “hot tub”, posted January 31, 2017





Expert witness forum looks at bias and other touchy subjects in forensic work

I attended an expert witness conference in Toronto last week and it was very good.  I’ve attended these types of conferences in the US in the past and they were also good.  But Toronto was different in its Canadian flavour and in addressing touchy subjects like bias in expert investigating and reporting, “dirty” experts and retaining experts on contingency.

I’m not so sure about the prevalence of these problems down east but in my invited talk on Principles Governing the Cost Control of Civil Litigation Involving Experts I touched on problems we do have.  Like experts retained many many months or years after a case is taken and technical investigation budgets estimated by non-technical people.

The two and a half day, 3rd Annual Expert Witness Forum East organized by The Canadian Institute, Toronto, looked in depth at:

  • Implicit bias as seen by three Toronto police officers, and,
  • Expert report writing as outlined by an experienced forensic engineer.

There was also good coverage of related topics like:

  • Case law and updates to the Rules of Civil Procedure
  • Breaking the logjam between experts and judges
  • Trends in expert witness testimony
  • Matching expertise to your case and,
  • Principles governing the cost control of civil litigation involving experts

The treatment of implicit bias was an eye-opener.  We’re human and it’s going to happen, it’s not always intended, but sometimes it’s deliberate.

Two of my daughters were interested in the conference program as well; I suspect because of the bias theme.  One is in hospital management in Toronto, and the other in veterinary medicine in the US who actually expressed some interest in attending.  So, wide appeal for the forum.

I took copious notes and hope to report in more depth on the conference but think I’ll wait on receipt of the speaker’s papers to be sure I get it right.  Particularly that on bias and report writing.  These views need to be got out there to all involved in expert witnessing on both sides of the table.

There’s an Expert Witness Forum West, and a Forum East which I attended.  There’s an argument for an Expert Witness Forum Way Down East.

I noticed some quite different practices being talked about in Toronto.  We know about bias and it was good to air it – for sure the situation is similar down east.  But the suggestion about retaining an expert on contingency even if under contract was a shocker.  Perception-is-everything would be the Achilles’ heel for that idea.

I think reference to ”dirty” experts is an unfair misnomer for “consulting” experts, a valuable and less expensive role for an expert in civil litigation compared to testifying expert.  Experts down east for the most part are objective in their investigative work and when advising an advocate for an injured party.  The most they can be faulted for is advocating for their findings.