“But I don’t want to be an expert”

By David Debenham, President of the ACFI, counsel of Low Murchison Radnoff, LLP (Ottawa)

Lawyers presume that all of their professional witnesses have to be qualified as experts. Do they?

Under Rule 701 of the American Federal Rules of Evidence, a witness is not testifying as an expert, if the witness testimony is limited to one that is (a) rationally based on the witness’s perception; (b) helpful to clearly understanding the witness’s testimony or to determining a fact in issue; and (c) not based on scientific, technical, or other specialized knowledge.

Lay testimony has surprising breadth. For example, most courts have permitted the owner or officer of a business to testify to the value or projected profits of the business, without the necessity of qualifying the witness as an accountant, appraiser, or similar expert, [1]  as it is based on his knowledge and participation in the day-to-day affairs of the business). Such opinion testimony is admitted not because of experience, training or specialized knowledge within the realm of an expert, but because of the particularized knowledge that the witness has by virtue of his or her position in the business. 

In Brown[2], the court declared that the distinction between lay and expert witness testimony is that lay testimony “results from a process of reasoning familiar in everyday life,” while expert testimony “results from a process of reasoning which can be mastered only by specialists in the field.” 

The Federal Rules do not distinguish between expert and lay witnesses, but rather between expert and lay testimony. Certainly, it is possible for the same witness to provide both lay and expert testimony in a single case. [3] (law enforcement agents could testify that the defendant was acting suspiciously, without being qualified as experts; however, the rules on experts were applicable where the agents testified on the basis of extensive experience that the defendant was using code words to refer to drug quantities and prices). The amendment makes clear that any part of a witness’ testimony that is based upon scientific, technical, or other specialized knowledge is governed by the standards of expert testimony.

A summary is typically presented as a chart, summary, or calculation, often presented by the witness who prepared it and is familiar with its contents; a summary can, however, simply take the form of a witness’s oral testimony.7 There are three types of summary evidence: (1) summaries of voluminous records [4](2) pedagogical summaries of evidence allowed by the court through its discretion under Federal Rule of Evidence 61 1(a); and (3) “hybrid” summaries which perform both functions in an effort to reliably assist the factfinder. Summaries contain voluminous writings, recordings, or photographs which cannot conveniently be examined in court so they may be presented in the form of a chart, summary, or calculation.  These charts are only admissible where the underlying documents they purport to summarize would be admissible.  Although the Federal Rules of Evidence do not explicitly allow – or require – the proponent of a summary chart to have the preparer come into court as a witness to explain the chart, courts have held that such testimony

is within the broad discretion of the trial court to admit or exclude evidence. These witnesses need not be experts to sift through the documents being summarized. 

By contrast, pedagogical summaries are not evidence themselves, but are demonstrative evidence used  used merely as an aid to the jury by allowing a witness to review testimonial or other evidence that has been introduced during a trial.   These pedagogical summaries apparently serve the twin aims of (a), the efficient “ascertainment of the truth” and (b) the avoidance of “needless consumption of time.

The third category is the hybrid secondary-evidence summarizing evidence and explaining its significance to the fact finder.

In R. v. Vuong [1]the crown was prosecuting a fraud over $5,000 in relation to a large-scale investment scheme. Owing to there being no prejudice, the Court of Appeal for Ontario dismissed the appellants’ application that the trial judge erred by permitting a forensic accountant to testify as a non-expert witness. The ruling permitting the forensic accountant to testify as a fact witness was focused on a “Source and Application of Funds” Analysis. His evidence was limited to following the flow of money deposited by the various complainants through the accuseds’ bank accounts.In his report, the accountant made findings, for example, that payments to investors could only have been funded by other investor deposits. That is an opinion. He also opines that the trading was speculative and not profitable. Those are also conclusions made based on his review of the underlying facts and not just a resuscitation of the facts based on his experience and knowledge as a forensic accountant. The trial judge originally found that the opinions rendered the accountant an expert.  Then the Court of Appeal released its decision in R. v. Ajise, [2] In Ajise, the majority held that a Canada Customs and Revenue Agency (“CCRA”) investigator did not have to be qualified as an expert witness because the witness offered only factual information that did not require expertise to present and could be assessed by the jury as a matter of logic and common sense. The trial judge then reversed herself and held that the accountant could be called as a non-expert witness, so long as he not to proffer any opinion evidence at trial.


In your case, are you really proffering an opinion that depends on your expertise, an opinion that any lay witness could come to, or simply a summary of facts?  The answer to this question can make all the difference in the world regarding whether you testify, and how.


[1] R. v. Vuong and Quach, 2018 ONSC 3631 (CanLII), <https://canlii.ca/t/ht7kj>

[2] 2018 ONCA 494, 361 C.C.C. (3d) 384, aff’d 2018 SCC 51, [2018] 3 S.C.R. 301.

[1] See, e.g., Lightning Lube, Inc. v. Witco Corp4 F.3d 1153 (3d Cir. 1993)

[2]  836 S.W.2d 530, 549 (1992),

[3] See, e.g., United States v. Figueroa-Lopez, 125 F.3d 1241, 1246 (9th Cir. 1997)

[4] as provided in Federal Rule of Evidence 1006;