Stepping into the Hot Tub: Concurrent Expert Evidence in Commercial Arbitration

• Author: Dominique T Hussey & Will Bortolin
• Pages: 335-360

335

chapter twelve

Stepping into the Hot Tub: Concurrent

Expert Evidence in Commercial

Arbitration

dominiQuE t hussEy & Will bortolin

A. INTRODUCTION

The presentation of expert evidence in commercial arbitration

has generally mirrored that in litigation before the courts: Highly

qualied experts appear sequentially before the decision maker,

each party hopes that its expert’s opinion will be adopted and its

opponent’s disregarded, and opinions are elicited and tested only

through counsel’s questions. The result is often that the experts

speak at cross-purposes and advocate rather than elucidate. Char-

isma and craftiness assume the signicance of credentials and

eclipse the quality of the opinions.

Many litigants are dissatised with the traditional method

of adducing expert evidence. The common complaints are that

(1) the other party’s expert witness evidence suers from bias, (2)

adjudicators lacking subject matter expertise struggle to resolve

contradictory opinions, and (3) the process is tedious, time-con-

suming, and costly.

Concurrent expert evidence, also known as hot tubbing or

expert panels, is an alternative method of presenting expert evi-

dence to a tribunal. The core feature is that experts having con-

tradictory views are sworn in at the same time and invited to

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engage in a direct dialogue with a view to explaining, explor-

ing, and potentially resolving their dierences. This method rst

rose to prominence in Australia and has since drawn keen inter-

est from the judicial systems in the United Kingdom, the United

States, and Canada. There are also anecdotal reports of its use in

private arbitrations.1

As the method has made its way to the Canadian courts and

appears to be here to stay, its use in commercial arbitration will

naturally follow. Canadian legal practitioners should therefore

understand the advantages and pitfalls of “hot tubbing.” This

chapter discusses the function of expert evidence and its associ-

ated problems. It then evaluates the purported advantages of hot

tubbing in addressing these problems as experienced in several

jurisdictions and concludes with a suggested framework for as-

sessing whether hot tubbing would be appropriate in a particular

commercial arbitration.

B. THE FUNCTION OF EXPERT EVIDENCE IN

RESOLVING DISPUTES

Expert evidence serves two distinguishable functions. The rst

is informational. In a dispute that involves sophisticated subject

matter, as commercial arbitration often does, the adjudicator may

need help understanding basic principles or background facts ne-

cessary to resolve the dispute. The expert’s “opinion” here func-

tions as factual evidence, which feeds into the legal tests that the

adjudicator will apply. In a patent infringement case, for example,

experts are often called upon to opine on what a “person of ordin-

ary skill” in a particular eld would have known or believed as of a

historical date. With the benet of that information, the adjudica-

tor can determine how the patent should be interpreted, whether it

has been infringed, or whether the patented subject matter was in-

deed inventive and therefore validly granted as of the relevant date.

1 See Doug Jones, “Recent Developments in International Commercial Arbi-

tration” (2008) 11 International Trade and Business Law Review 83 at 104–5.