Expert Witness Report:

Question:What should Ontario litigators and proposed expert witnesses include to prepare an admissible expert witness report for court?

Answer:Legacy Legal Services can help legal professionals and proposed expert witnesses in Ontario understand the requirements for an expert witness report that is more likely to be admitted and relied upon by the court, including meeting the R. v. Mohan criteria, being properly qualified, and clearly linking the opinion to the evidence through a readable, proofed, well-referenced structure with appendices, bibliography, and defined terminology, while also avoiding biased wording and unnecessary criticism of other experts.   To reduce the risk of an inadmissibility challenge, get the report scope confirmed with counsel, use professional formatting (cover page, index, headings, clear summaries, and consistent page and appendix references), and ensure the expert’s conclusions reflect an unbiased view grounded in authentic reasoning.   If you need to prepare or tighten an expert report for litigation in Ontario, call (226) 246-3825 to discuss your matter with Legacy Legal Services.

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Understanding the Requirements When Preparing an Expert Witness Report Document for Court Litigation Purposes

Various best practice habits when preparing expert reports can help ensure a well-crafted document that is both effective and efficient for use within the courtroom. Indeed, a quality expert report can be the difference in making or breaking a case; and accordingly, the choice of expert, the style of report, and the manner used when expressing expert opinion, require careful review.

Note: Please contact Legacy Legal Services by phone at: (226) 246-3825 to discuss any specific questions that you may have.

The Law

Admissibility

For a court to admit an expert report as evidence the expert report must meet the criteria of admissibility.  The criteria was summarized within the case of 2599475 Ontario Inc. v 2549445 Ontario Inc., 2023 ONSC 3508, where it was said:

Quality Expert Reports

Communicate Clearly and Effectively

Prior to drafting a report, the expert should review the required scope of the report with the representative, being the lawyer or paralegal, who seeks the report.  Depending on the nature of the court case, the report may require broad details or may require a narrow focus.  In some circumstances, a brief report is adequate; and in other circumstances a more lengthy report is necessary.  Forgoing this review can result in the waste of preparing an insufficient report or the waste of preparing an excessive report.  Either is a waste of time and therefore money.

A proper expert report includes, and properly references, the evidence documents that support the expert opinions and conclusions. The expert opinion contained within a report should, and perhaps must, refer to supporting evidence documents such as pictures or testing results, among other things, attached as appendices or schedules. A bibliography referencing any authoritative documents or studies that are used to support opinions and conclusions should also be included.

An expert report should express opinions clearly and concisely while being easy to read in an organized and professional layout with spelling, grammar, and punctuation, carefully reviewed for correctness.  The expert report should be written with a vernacular and tone that is consistent with the language of the intended audience whereas, for example, differences may be required for legal cases heard by a judge versus legal cases heard by a jury; and accordingly, language should remain within the understanding of the average layperson while avoiding belittlement of judges, lawyers, and other experts.  Reports should be careful to limit the use of industry specific jargon or abbreviations known only to those with expertise within the relevant field; and, where industry jargon or abbreviations are necessary, a reference table or key to provide definitions should be provided within the report.

More Hints

• Use professional letterhead;
• Use a cover page as well as an index or table of contents;
• Use a curriculum vitae or resume to summarize the qualifications and credentials that confirm that the expert is genuinely an expert;
• Use an introduction page to outline when, and from whom, the report was requested;
• Use 12-point font and double spacing;
• Use headings;
• Use short, concise paragraphs;
• Use a unique reference number for each page, table, chart, and appendix;
• Use a definitions page or section to define technical language and industry specific jargon or abbreviations; and
• Use an upfront summary page to outline final conclusions or opinions.

Things to Avoid

An expert report must be impartial and objective.  The role of an expert is to provide an unbiased opinion to the court for the purpose of aiding in the truth-seeking mission of the court.  The expert must therefore ensure that the expressed opinion is grounded in facts and evidence rather than prepared with a favouring of a litigant.

• Avoid absolute wording and phrasing;
• Avoid words that appear as hedging or guessing;
• Avoid critical commentary regarding credibility of other experts;
• Avoid a scientific and clinical tone by keeping the tone friendly and personable;
• Avoid going into details beyond the purpose of the report;
• Avoid unnecessary adjectives or superlatives.

Summary Comment

The expert preparing an opinion report must remain attentive to the balance required when obtaining input from a legal representative whereas the lawyer or paralegal seeking the report will best understand the factual concerns and legal issues that relate to why the report is needed and can explain the desired scope; however, the findings and opinions as stated within the report must always remain the genuine unslanted view of the expert as author of the report.