Il est approprié pour l’avocat de réviser et de discuter du projet d’expertise (draft report) avec l’expert.
 Third, 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 counsel improperly influenced an expert witness. Judges have not shied away from rejecting or limiting the weight to be given to the evidence of an expert witness where there is evidence of a lack of independence or impartiality. In Medimmune, at para. 111, the court noted that “partisan expert evidence is almost always exposed as such in cross-examination, which is likely to reduce, if not eliminate, the value of the evidence to the client’s case”; see also Alfano v. Piersanti, 2012 ONCA 297, 291 O.A.C. 62, at paras. 106-120.
 I agree with the submissions of the appellant and the interveners that it would be bad policy to disturb the well-established practice of counsel meeting with expert witnesses to review draft reports. Just as lawyers and judges need the input of experts, so too do expert witnesses need the assistance of lawyers in framing their reports in a way that is comprehensible and responsive to the pertinent legal issues in a case.
 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.
 For these reasons, I reject the trial judge’s proclamation that the practice of consultation between counsel and expert witnesses to review draft reports must end. However, as I will discuss below, the trial judge’s unwarranted criticism of the appellant’s counsel on this basis did not, in my view, affect the outcome of the trial.
La protection conférée par le privilège relatif au litige s’étend également aux notes, enregistrements ou toute autre consultation entre l’expert et l’avocat, et ce, même si la partie compte faire témoigner l’expert.
 Pursuant to rule 31.06(3), the draft reports of experts the party does not intend to call are privileged and need not be disclosed. Under the protection of litigation privilege, the same holds for the draft reports, notes and records of any consultations between experts and counsel, even where the party intends to call the expert as a witness.
 Making preparatory discussions and drafts subject to automatic disclosure would, in my view, be contrary to existing doctrine and would inhibit careful preparation. Such a rule would discourage the participants from reducing preliminary or tentative views to writing, a necessary step in the development of a sound and thorough opinion. Compelling production of all drafts, good and bad, would discourage parties from engaging experts to provide careful and dispassionate opinions and would instead encourage partisan and unbalanced reports. Allowing an open-ended inquiry into the differences between a final report and an earlier draft would unduly interfere with the orderly preparation of a party’s case and would run the risk of needlessly prolonging proceedings.