Canada: Non-Testifying Experts Are Now To Produce All Background Information

Evaluating the strength of a plaintiff's claim just got a bit more complicated. Following a new Superior Court decision, the common practice of retaining an expert just to advise on the merits of the case has been put under more scrutiny, and a manufacturer and its counsel will have to be more cautious in sharing information with their experts – even if those experts will never see the inside of a courtroom. In Andereason v. The Corporation of the City of Thunder Bay ("Andereason"), Justice D.C. Shaw was asked to rule on the extent of expert data that must be disclosed to a plaintiff before the defendant has decided whether or not to call that expert as a witness at trial. The defendant in this case had served the expert's report on the plaintiff, but had not yet decided whether that expert would give evidence at trial. The plaintiff sought production of the underlying data the expert used to generate her report, as well as the expert's entire file.

The Ontario Rules of Civil Procedure allow for discovery of the "findings, opinions and conclusions" of an expert unless:

(a) they were made in preparation for contemplated or pending litigation; or

(b) the party undertakes not to call the expert as a witness at trial. 

The Rule makes no mention of data provided to the expert. The question before the Court was where to draw the line between a litigation-privileged report and file, which the Rule protects, and the potentially unprotected foundational evidence from which the expert drew her conclusions. In this case, some degree of litigation privilege had already been waived since the report had been served, but the Court's ruling as to the foundational data did not hinge on that fact.

Upon reviewing the caselaw, the Court came to two major conclusions. 

First, the Court adopted the following principles as set out by Master Short in Aherne v. Chang ("Aherne"):

1)    If information is sent to an expert, then the same information should be sent to the opposing party to allow that party to test the expert's opinion.

2)    An opposing party is entitled to the facts on which the expert's opinion is based.

3)    So long as an expert read a document sent to him or her, then that document was considered, such that it is a finding that must be produced.

4)    The privilege claimed over a document sent to an expert is waived at the time that it was decided to rely on that expert's opinion or in circumstances where privilege is waived over the report, even if the waiver was inadvertent.

5)    By sending a defence medical assessor portions of surveillance, privilege over the full surveillance video or all photographs is waived.

The case of Aherne, however, concerned experts that were definitely going to provide evidence – either as experts in court or under the Rules concerning defence medical examinations. 

In Andreason, the Court took a step further, finding that foundational information underlying an expert's report must be provided regardless of whether the expert will testify or not.

Product manufacturers and their counsel ought to be cognizant of this development, as it complicates the practice of hiring an expert to determine the strength of a case. The Court has now ruled that whatever information is available to one party for the purposes of seeking expert advice, must also be provided to the other party.

On the one hand, this strikes a blow for trial fairness by ensuring that this information, which is relevant to the resolution of the claim, is distributed to both sides and that their dispute resolution process is transparent. Settlement will be easier and more fair, and cross-examinations more efficient, by eliminating information asymmetry.

On the other hand, it is now incumbent upon manufacturers and their counsel to think twice before retaining an expert purely to advise them about the scope of their exposure or the merits of their case. They must be particularly cautious not to provide any proprietary or confidential background information to such an expert unless it is:

(a) necessary for her to arrive at her conclusion; and

(b) sufficiently relevant and proportional to the case that it will have to be disclosed in any event.

Key Takeaway Principle:

As the court system continues to progress towards a more open and transparent environment in terms of expert witnesses, the Andreason case marks a milestone after which all defendants have to assume that anything passing before the eyes of an expert – any expert, retained for any reason – could well pass before the eyes of the plaintiff.  

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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