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Posted in: Ontario Court of Appeal | Ontario | Practice & Procedure

May 11, 2015

Ontario Court of Appeal Clarifies Procedures for Communicating with Expert Witnesses

In Moore v. Getahun (2015 ONCA 55), the Ontario Court of Appeal recently provided much needed clarification to the limits governing appropriate communications between lawyers and expert witnesses following the 2014 Superior Court decision of Justice Wilson (2014 ONSC 237), which called into question the long-standing practice of lawyers assisting expert witnesses in the preparation of their evidence.

Justice Wilson held that lawyers must stop reviewing draft reports and must significantly restrict their communications with experts in order to ensure that expert witnesses meet their duty to the court to provide fair, objective and non-partisan evidence.[1] Any input from a lawyer, Justice Wilson held, was only appropriate after the expert's report was finalized and only for the limited purpose of clarification or amplification of any part of the report. Furthermore, all communication for that limited purpose should be in writing and should be disclosed to opposing lawyers.[2]

Justice Wilson's comments raised questions as to whether or not the recommended restrictions on communications with experts would apply in proceedings before administrative tribunals, like the Ontario Energy Board (Board). Experts appearing before the Board have a similar duty of impartiality as those appearing in civil court proceedings. Experts before the Board are required to give evidence that is "fair and objective."[3] The Board has stated that the purpose of expert evidence is not to advocate on behalf of any party, but to assist the Board in understanding the issues in dispute.[4] However, just as in civil proceedings prior to Justice Wilson's ruling, it has been common practice for lawyers to review and discuss draft reports with the experts retained to provide evidence before the Board. Justice Wilson's decision had put that practice into question. Were the restrictions on communications with experts as prescribed by Justice Wilson necessary to ensure impartiality of experts in the context of proceedings before the Board?

The decision of the Court of Appeal has now resolved the uncertainty around this issue in favour of retaining the long-standing practices governing communications between lawyers and expert witnesses. The Court of Appeal unanimously rejected Justice Wilson's conclusions on the issue deciding that, not only is consultation and collaboration between a lawyer and expert witness appropriate, it is "essential" to ensure that the expert witness understands his or her duties in a legal proceeding. Further, the Court of Appeal held that such consultation is in the interests of justice and efficiency as it enables a lawyer to ensure that the expert report complies with the applicable procedural rules and rules of evidence, addresses and is restricted to the relevant issues and is written in a manner that is accessible and comprehensible.[5] Lawyers, the Court of Appeal held, "play a crucial mediating role by explaining the legal issues to the expert witness and then by presenting complex expert evidence to the court."[6]

The Court of Appeal noted that the restrictions outlined by Justice Wilson were not necessary as the independence and objectivity of expert witnesses is fostered under existing law and practice in the following ways:

  • Ethical and professional standards of the legal profession forbid lawyers from engaging in practices likely to interfere with the independence and objectivity of expert witnesses;[7]
  • Ethical standards of other professional bodies place an obligation upon their members to be independent and impartial when giving expert evidence (e.g. engineers, actuaries, chartered business valuators, etc.);[8] and
  • The adversarial process, particularly through cross-examination, provides an effective tool to deal with cases where there is an air of reality to the suggestion that lawyers improperly influenced an expert witness.[9]The Court of Appeal's decision in Moore v. Getahun endorsing the long-standing practices governing interactions between lawyers and expert witnesses resolves the uncertainty created by Justice Wilson's decision, not only in the context of civil litigation, but also for administrative tribunals that regularly hear expert evidence. Provided that lawyers and expert witnesses adhere to their professional ethical obligations, there ought to be no concerns within Board proceedings about the independence and objectivity of expert witnesses.

The existing practices cited by the Court of Appeal as fostering the independence and objectivity of expert witnesses are also found in the context of hearings before the Board. Lawyers appearing before the Board are bound by the same ethical and professional standards as lawyers appearing in court. Further, many of the experts retained to provide evidence within Board proceedings are themselves subject to the ethical standards of their professions, including engineers, accountants and others. Finally, hearings before the Board allow for the cross-examination of expert witnesses whereby any improper influence may be exposed.



[1] Moore v. Getahun, 2014 237 at para 520.

[2] Ibid at para 299.

[3] Ontario Energy Board, Rules of Practice and Procedure, Rule 13A.02.

[4] EB-2012-0031, Decision on Procedure for Oral Hearing of Concurrent Expert Evidence and Procedural Order No. 12 (February 1, 2013).

[5] Moore v. Getahun, 2015 ONCA 55 at para 63.

[6] Ibid at para 64.

[7] Ibid at para 57.

[8] Ibid at para 60.

[9] Ibid at para 61.