“During the trial both parties put enumerable texts and emails into evidence. These contained many self-serving, prior consistent statements by each of them. Tendered as part of the narrative, in my view, a more rigorous application of the rules of evidence is called for.
The general rule is set out in Sopinka, Lederman & Bryant, The Law of Evidence in Canada, 4th ed at paras. 7.1 to 7.3:
There is a general rule against the admission of self-serving evidence to support the credibility of a witness unless his or her credibility has first been made an issue. The rule is generally applied to prior consistent statements of the witness. A witness, whether a party or not, may not repeat his or her own previous statements concerning the matter before the court, made to other persons out of court, and may not call other persons to testify to those statements. Although contradictory statements may be used against a witness, “you are not entitled to give evidence of statements on other occasions by the witness in confirmation of her testimony.”
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Different rationales have been given for the exclusion of such evidence. The one most commonly relied on is that, due to the risk of fabrication, no person should be allowed to create evidence for him or herself.
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Justice Pepall in R. v. B. (D.), added that:
The repetition is self-serving and the source lacks independence. Lastly, given that the evidence will have already been adduced at trial through oral testimony, exclusion of prior consistent statements serves the desirable objective of trial efficiency.
Moreover, it would take needless trial time in order to deal with a matter that is not really in issue, for it is assumed that the witness is truthful until there is some particular reason for assailing his or her veracity.
More recently the Ontario Court of Appeal decided R. v. B.Z., 2017 ONCA 90 (CanLII), [2017] O.J. No. 512. The Court overturned a conviction for sexual assault based on the trial judge’s use of the complainant’s prior consistent statement. Shortly after the alleged assault she had sent an anonymous email to the police saying the appellant had sexually assaulted her. Her description of the assault in the email was consistent with her trial testimony. The trial judge was held to have erred in relying on the email as corroboration of her trial testimony, a use of the prior consistent statement which was dependent on the truth of its contents.
The Court of Appeal confirmed that a prior consistent statement may be admissible for an evidentiary purpose for which the truth of its contents is irrelevant. For example the fact of sending of an email, the fact of a response to an email, or the fact of a failure to follow-up on an email may be relevant, independently of the truth of the contents of the email.
It may be that a contemporaneous email could be used if necessary to refresh a witness’s testimony, to confirm the date of an event, or by the opposing party for purposes of cross examination. But the wholesale use of emails and text messages as the platform from which to testify should be curtailed.”