As courts around the world continue to grapple with the complex technical and scientific issues raised in toxic tort and product liability lawsuits, some U.S. commentators have recently looked to Australia where the “concurrent evidence procedure,” also known as “hot tubbing,” may provide a cost-effective and efficient way for factfinders to sort through the challenging expert witness battles that often confront them.  

According to University of New South Wales School of Law Professor Gary Edmond, the procedure allows “experts from similar or closely related fields to testify together during a joint session. The openings of these sessions tend to be more informal than examination-in-chief (that is, direct) and cross-examination, which are associated with conventional adversarial proceedings.” “Merton and the Hot Tub: Scientific Conventions and Expert Evidence in Australian Civil Procedure,” Law & Contemporary Problems (2009).  

Edmond also notes that “[f]or at least part of their testimony, experts are freed from the constraints of formally responding to lawyers’ questions. During concurrent-evidence sessions, expert witnesses are usually presented with an opportunity to make extended statements, comment on the evidence of the other experts, and are sometimes encouraged to ask each other questions and even test opposing opinions.” While Edmond concludes that the practice “is not a panacea for partisanship, adversarial bias, or the difficulties created by expert disagreement and decisionmaking in the face of uncertainty,” he concedes that it does have “the potential to improve communication and comprehension in the courtroom.”  

At least two U.S. legal commentators have recently seized on the idea and believe that it could significantly improve the presentation and evaluation of scientific expert testimony here. Scott Welch, writing in the Journal of International Commercial Law & Technology, states, “Granted, the procedure stands in stark contrast to the traditional adversarial methods of conducting expert witness examination used in American courtrooms; it seemingly fits in well with the liberal interpretation of the Federal Rules of Civil Procedure and Evidence.” “From Witness Box to the Hot Tub: How the ‘Hot Tub’ Approach to Expert Witnesses Might Relax an American Finder of Fact,” Vol. 5, Issue 3 (2010).  

Megan Yarnall, who authored “Dueling Scientific Experts: Is Australia’s Hot Tub Method a Viable Solution for the American Judiciary?” published in the Oregon Law Review, concludes that this innovative approach, while it may require modification for use in U.S. courts, would provide “significant improvements in the presentation and evaluation of scientific expert testimony.” Both commentators were particularly enthusiastic about adopting the procedure during pretrial proceedings, such as hearings testing the admissibility of expert testimony under Daubert v. Merrell Dow Pharmaceuticals, Inc. 509 U.S. 579 (1993).