Following a controversial earlier decision, the Court of Appeal for Ontario has clarified the scope for lawyers to speak to expert witnesses. The outcome appears similar to the position in Australia.
John O’Sullivan wrote:
Ontario litigators breathed a sigh of relief last Thursday when the Court of Appeal overturned a trial judge’s ruling that it was improper for a lawyer to review and discuss draft expert reports with an expert witness, and that such discussions must be documented and disclosed to an opposing party….
The court concluded the well-established practice of counsel meeting with expert witnesses to review draft reports should not be disturbed.
In Moore v Getahun  ONCA 55 at  – :
 Consultation and collaboration between counsel and expert witnesses is essential to ensure that the expert witness understands the duties reflected by rule 4.1.01 and contained in the Form 53 acknowledgment of expert’s duty. Reviewing a draft report enables counsel to ensure that the report (i) complies with the Rules of Civil Procedure and the rules of evidence, (ii) addresses and is restricted to the relevant issues and (iii) is written in a manner and style that is accessible and comprehensible. Counsel need to ensure that the expert witness understands matters such as the difference between the legal burden of proof and scientific certainty, the need to clarify the facts and assumptions underlying the expert’s opinion, the need to confine the report to matters within the expert witness’s area of expertise and the need to avoid usurping the court’s function as the ultimate arbiter of the issues.
 Counsel play a crucial mediating role by explaining the legal issues to the expert witness and then by presenting complex expert evidence to the court. It is difficult to see how counsel could perform this role without engaging in communication with the expert as the report is being prepared.
 Leaving the expert witness entirely to his or her own devices, or requiring all changes to be documented in a formalized written exchange, would result in increased delay and cost in a regime already struggling to deliver justice in a timely and efficient manner. Such a rule would encourage the hiring of “shadow experts” to advise counsel. There would be an incentive to jettison rather than edit and improve badly drafted reports, causing added cost and delay. Precluding consultation would also encourage the use of those expert witnesses who make a career of testifying in court and who are often perceived to be hired guns likely to offer partisan opinions, as these expert witnesses may require less guidance and preparation. In my respectful view, the changes suggested by the trial judge would not be in the interests of justice and would frustrate the timely and cost-effective adjudication of civil disputes.