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The Duties of Expert Witnesses

Wendy Reynolds from Slaw recently posted on a proposed regulatory change to the Rules of Civil Procedure with respect to the duties of expert witnesses. Coming into force in two years, the December 27, 2008 Ontario Gazette lists several amendments to the Rules of Civil Procedure including:



Duty of Expert

  It is the duty of every expert engaged by or on behalf of a party to provide evidence in relation to a proceeding under these rules,

(a) to provide opinion evidence that is fair, objective and non-partisan;

(b) to provide opinion evidence that is related only to matters that are within the expert’s area of expertise; and

(c) to provide such additional assistance as the court may reasonably require to determine a matter in issue.

Duty Prevails

(2) The duty in subrule (1) prevails over any obligation owed by the expert to the party by whom or on whose behalf he or she is engaged.  


It will be interesting to see what impact, if any, this amendment will have on the duties of expert witnesses. Case law already suggests expert witnesses are already required to report in an independent manner and cannot been seen as an advocating for the party that retains them. The strength of an expert witness comes from their objective evidence and the evidence of an expert witness will be rejected if they are bias.


Does this proposed Rule merely confirm the well established principles of expert evidence as it has developed in case law or does it go beyond establishing the independence of an expert witness? Are we moving towards the use of joint experts to assist the Court? We have a few years to find out.


Thanks for reading,


Diane Vieira