Expert Witness Report: A Well Documented and Supported Opinion from a Subject Matter Expert

Question: What are the key components of a successful expert witness report in court?

Answer:   A successful expert witness report must adhere to the criteria for admissibility, which include relevance, necessity, and proper qualifications, as outlined in R. v. Mohan, 1994 CanLII 80 (SCC).  It's crucial to communicate clearly and precisely, focusing on the intended audience, to ensure the report is understood by all parties, including judges and lawyers.  White Owl Legal assists clients in preparing meticulous expert witness reports that meet all legal standards and support their cases effectively.  Ensuring your report is thorough and well-organized can make a significant difference in court proceedings. 

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

A proper, well crafted, expert witness report can make the difference between success or failure within a lawsuit; and accordingly, avoiding mistakes within an expert report is of utmost importance so to ensure that the expert report is admissible, and may be relied upon, within the court proceeding. If an expert report is deemed inadmissible, such may jeopardize the legal case.

The Law

Admissibility

When reviewing whether to admit an expert report as evidence, a court will seek to ensure that the report meets the required admissibility criteria.  Expert evidence admissibility criteria summarized within 2599475 Ontario Inc. v 2549445 Ontario Inc., 2023 ONSC 3508, whereas it was stated:

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.

It is also necessary that the supporting evidence documents reviewed by the expert are adequately included and properly referenced.  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.  Additionally, a bibliography to summarize any authoritative documents used for research should be included.

The report should read clearly with ease and appear professional and proofed for proper spelling, grammar, and punctuation.  The expert should write in a style directed towards the intended audience, balancing need that the report be understood by an average layperson without belittling highly intelligent judges and lawyers or other experts.  Reports should omit or limit industry specific jargon and abbreviations; but, if such is necessary, include definitions 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

A biased or slanted expert report can be disastrous – and should be!  The expert is expected to provide opinion as a friend of the court for the primary purpose of assisting the court in the truth finding effort.  The expert, while having an opinion that may favour one litigant over another, must base the opinion on authentic reasons rather than as friend 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.