Biased experts cured with a soak in the “hot tub”

Intentional and unintentional bias is a fact of life in forensic investigation and reporting, in life in general for that matter.  Fortunately, there is a solution to the problem and one that will benefit from formal rules governing experts, like Rule 55 in Nova Scotia, when the bias-solution comes to the Atlantic provinces.

The bias-problem was reported in a story in the National Post with the headline “Hired gun in a lab coast: How medical experts help car insurers fight accident victims”. (Ref. 1)  Judges in Ontario noted the bias in the investigation and reporting of some medical doctors on injuries from car accidents.  Also the money they earned from companies who were favoured in the medical reports.

The problem is not unique to the medical profession.  Bias exists in the work of those in different professions and vocations.  I’ve seen it in reports during my engineering work in the Atlantic provinces – blatant bias in one report recently.

The solution to the problem was also noted in the National Post.  It’s the “hot tub” method in which experts give their evidence concurrently.  It was developed in Australia and is getting good reviews in the UK.  It’s being looked at in the US and Canada.

An Australian judge, Justice Steven Rares, gives a detailed explanation of the method with 46 references. (Ref. 2)  The “hot tub” label is obvious on reading Rares’ paper.  The Australian courts have been acknowledged as having the most experience in this technique dating back to about 1985. (Ref. 2)

Briefly, the way it works: After each expert has prepared his or her evidence they confer in a pre-trial meeting, without lawyers.  During the meeting they prepare a joint report on the matters about which they agree and those on which they disagree, giving short reasons as to why they disagree. (Ref. 2)

At trial – in the unlikely event it goes that far – the experts meet again and each is asked to identify and explain the principal issues as they see them, and each is given the opportunity to comment and ask questions of the others. Counsel then has the opportunity to examine the joint report and the experts’ comments on it. (Ref. 2)

There is resonance between this method and the requirements of the formal and strict rules governing experts and their reports. Well written reports by experts retained by opposing parties are a near perfect fit with the “hot tub” solution.

The growing bulk of the academic and legal papers on the topic seem to agree it’s a good idea. (Ref. 3)  However, there is a view by some that the formality of the new rules governing experts and their reports reduces the possibility of discussion amongst experts – key to the “hot tub” method. (Refs 2, 3)

I believe that problem will be overcome because most cases don’t go to trial – and even in the few that do, the solution involving experts’ reports will be made to work because it’s needed.  Well written expert reports and agreement amongst experts, as presented in a joint report, are essential to the successful and expedient resolution of disputes at all stages.

The “hot tub” method is working well in reducing bias, saving court time and reducing civil litigation costs. (Refs 2, 3)  That fact will carry the day.

It’s being called for in Ontario where judges see a bias-problem.  It would work well in the Atlantic provinces.

For certain it’ll work well in the hard sciences like engineering where we are disposed to working together to figure things out and solve problems, without getting cranky with one another.


  1. Blackwell, Tom, “Hired gun in a lab coast – how medical experts help car insurers fight accident victims”, National Post, January 7, 2017, page A7
  2. Rares, Steven, Judge of the Federal Court of Australia and an additional Judge of the Supreme Court of the Australian Capital Territory, “Using the “Hot Tub” – How Concurrent Expert Evidence Aids Understanding Issues”, October 12, 2013. Google, January 14, 2017
  3. van Rhijn, Judy, Hot-tubbing experts – should lawyers like it?, Canadian Lawyer July 4, 2011

(Posted by Eric E. Jorden, M.Sc., P.Eng. Consulting Professional Engineer, Forensic Engineer, Geotechnology Ltd., Halifax, Nova Scotia, Canada. January 31, 2017   

Where does civil litigation come from, and how much?

It comes from the built environment.  Exactly where in the environment and how problems can develop – and owners experience damage – is seen below in the answer to this question.  A simple, high-school-level multiplication at the end of this short blog – but first, a few easily understood comments on what’s involved in engineering..

Engineering at its best addresses the concerns and accommodates the interests of the parties involved at each stage in the life cycle of an engineered facility.

  1. Seeing a need
  2. Conceptualizing how to meet the need
  3. Planning
  4. Investigating
  5. Designing
  6. Constructing
  7. Inspecting
  8. Operating
  9. Maintaining
  10. Renovating
  11. Reconfiguring, and,
  12. Decommissioning

The goal of the engineering effort can be seen as satisfying the concerns of people at each of these stages, or at least dissatisfying them as little as possible.”  (Ref. 1)


I added Seeing a Need to this well thought-out list in Ref. 1 because you can’t conceptualize meeting a need until you recognize you’ve got one.

I added Investigating because it’s an important stage, particularly

  • for the part of a facility below the ground surface,
  • for earthworks of any kind,
  • for anything that impacts the environment and
  • when new materials and design and construction procedures are involved.

And I added Inspecting because it’s important to ensuring the facility is constructed according to the design, for the agreed cost.


Forensic engineering can be defined as applying engineering principles, knowledge and experience to problems and failures where legal liability may be decided in a legal forum.  However, much of the work of forensic engineering leads to the resolution of a problem without formal legal proceedings.” (after Ref. 1)

Failure can be defined as an unacceptable difference between an actual condition and the intended or reasonably anticipated condition of an engineered facility.  Failure may not involve a complete or even partial collapse.  It may involve a less catastrophic deficiency or performance problem such as unacceptable: (after Ref. 1)

  • potholes in the pavement,
  • foundation settlement,
  • structural movement and cracking,
  • earthworks, slope and retaining wall movement,
  • water and weather damage,
  • leaking roof,
  • environmental contamination,
  • structure and infra-structure maintenance,
  • repair of a problem, and,
  • mechanical and electrical equipment operation.”

One writer identified 209 ways a building can fail – and that was just in the part of the building above the ground surface. (Ref. 2)  A building can also fail in numerous ways below ground.  In fact, the part of the structure below ground – foundation, basement, utility pipes, drainage systems – is in many ways the most complex part to design and construct.  Not the most glamorous part, just the most complex.  Another writer identified numerous ways that a building’s basement and foundations can cause problems. (Ref. 3)

Contractors will tell you they are glad when they get out of the ground and start erecting the upper part of a structure.

A building is just one of the many 100s of different structures with their component parts that comprise the built environment – think about that, 1 of many 100s.  Look around next time you’re outside and count just the ones you see.

When can a structure fail in it’s life cycle – in the process from it’s inception and birth to it’s decommissioning at the end of it’s useful life?  At any of the 12 stages in the list above.

To answer the question, Where does civil litigation come from?  Count the places:

  • many 100s of different structures
  • multiplied by 100s of ways some can fail
  • multiplied by the 12 stages in an engineered facility’s life
  • multiplied by the different parties at each stage who might feel wronged and entitled to damages.

At it’s simplest, allowing two wronged parties at each stage, almost a quarter of a million ways that civil litigation can develop – 240,000.

I’m sure a similar calculation could be done for personal injury accidents in the built environment.  For example, the numerous slip, trip and fall accidents – likely more than the traffic accidents in the Atlantic provinces in 2016.


  1. Kardon, Joshua B., ed,, Guidelines for Forensic Engineering Practice, The American Society of Civil Engineers (ASCE), Reston, Virginia, 2012
  2. Nicastro, David H., ed., Failure Mechanisms in Building Construction, ASCE, Reston, Virginia, 1997
  3. The National Research Council of Canada, Performance Guidelines for Basement Envelope Systems and Materials, Final Research Report, April 2007