Sometimes expert witnesses attach lengthy appendices to their reports setting out the materials they have reviewed or interview summaries. Reasons for judgement were released today by the BC Supreme Court, Vancouver Registry, addressing this practice.
In today’s case (Maras v. Seemore Entertainment Ltd) a variety of expert reports were challenged prior to a lengthy jury trial. The Court struck several reports and in doing so provided a good overview of the law addressing admissibility of expert reports at paragraphs 9-20 of the reasons. In addressing the issue of expert report appendices Mr. Justice Abrioux provided the following comments:
 As outlined in Rule 11-6(1)(e) and (f), an expert’s report should clearly delineate between “facts and assumptions” and “opinion”. To the extent there is information in an appendix that is a fact or assumption upon which an expert relies, then that should be contained in the “facts and assumptions” section of the report itself. Likewise, to the extent an appendix contains an opinion, then that should be set out in the “opinion” section of the report. Generally speaking, appendices to the report should be streamlined, and only include what is necessary for the formulation of the expert’s opinion and/or the facts and assumptions upon which it is based.
 An appendix containing summaries and comments, to the extent that it does not contain an opinion or underlying facts and assumptions, is no more than a working paper which does not need to be included in the report itself. It should remain in the expert’s file, which is producible pursuant to Rule 11-6(8). As with any other document forming part of the expert’s file, it can be the subject of cross-examination.
 In deciding the threshold question of admissibility, I am also of the view that there is some assistance to be obtained from decisions of this court or administrative tribunals which consider the reasonableness of an expert’s fee on an assessment of costs. Although I recognize that the purpose of the analysis is different, the underlying issue is similar, that is, the necessity of the expert’s report and its assistance to the trier of fact.
 In that regard, there have been many instances in which Registrars or Masters of this court, when considering whether the amount charged by an expert is properly payable by the opposing party, have commented as to whether the charges were reasonable in the circumstances. Experts’ charges have been disallowed or reduced for a variety of reasons, including when the expert’s report contained improperly extensive narrative: Wheeldon v. Magee, 2010 BCSC 491 at paras. 20-29; Bodeux v. Tom, 2013 BCSC 2327 at paras. 20-23.
 Certain British Columbia Workers’ Compensation Appeal Tribunal (“WCAT”) decisions have also discussed the usefulness, or lack thereof, of lengthy appendices to expert reports. These comments appear within the context of WCAT’s discretion to order reimbursement for expert reports on the basis of a “reasonableness” analysis. For example, in WCAT-2013-02657 at paras. 75-85, it was said:
 In summary, although Ms. Gallagher’s report was helpful in my deliberations, and it was reasonable for the worker to obtain it, I find the reasons for its expense to be inadequate. The appendices to the report detailing the worker’s test results were not helpful to lay person. This information is summarized (or should be) in the body of the report. A summary of the evidence contained in the appendix, again, is not useful or appropriate considering it is on the claim file, and in the body of the report. …
Similar examples commenting on the reasonableness of lengthy appendices include WCAT-2012-01770 at paras. 105-107, and WCAT-2012-02617 at paras. 53-58.
 In a decision rendered since my oral ruling in this case, Madam Justice Russell recently summarized the law in this province regarding the scope of disclosure of an expert’s file pursuant to Rule 11-6(8): Conseil scolaire francophone de la Colombie-Britannique v. British Columbia (Education), 2014 BCSC 741 at paras. 25-51 [CSF]. After a thorough review of the relevant jurisprudence, she held:
 With regard to the scheme of the R. 11-6(8), I note that R.11-6(8)(a) enumerates a number of documents that must be served on a requesting party immediately, namely written statements or statements of facts on which the expert based his or her opinion; records of independent observations made by the expert in relation to the report; data compiled by the expert in relation to the report; and the results of any tests conducted by the expert or inspections conducted by the expert. Rule 11-6(8)(a) thus already requires production of the observations and analysis underlying the expert’s opinion. Rule 11-6(8)(b) should therefore be read as requiring production of something more than the underpinning of the report.
 My interpretation of R. 11-6(8)(b) thus takes a middle road between the broad scope of disclosure at common law and the narrow view asserted by the plaintiffs. As I see it, on request pursuant to R. 11-6(8)(b), an expert must produce the contents of the expert’s file that are relevant to matters of substance in his or her opinion or to his or her credibility unless it would be unfair to do so.
 The CSF decision, in my view, supports my conclusion that an expert’s report should be limited to the requirements set out in Rule 11-6(1). To the extent the recipient of the report requires production of further documents, then he or she is to follow the procedure in Rule 11-6(8).
 I would add that if a party seeks production of the contents of the expert’s file earlier than the 14 days before trial provided for under Rule 11-6(8)(b)(ii) and meets resistance in that regard, this could form the basis for a disclosure application at a trial management conference pursuant to Rule 12-2(9)(q).