The issue of how a trial judge is to assess a purported absence of motive to fabricate in assessing a witness’ (usually the complainant’s) evidence was considered by the British Columbia Court of Appeal in R. v. Swain, 2021 BCCA 207, May 26, 2021.

In Swain, the accused was charged with the offence of sexual assault. The only witnesses who testified at the trial were the accused and the complainant. In convicting the accused, the trial judge stated:  

Another conclusion mandated by Mr. Swain’s version of events is that, even though the brief encounter in the kitchen was witnessed by no one else, the complainant thereafter fabricated in her phone diary a detailed version of events involving multiple incidents of sexual interference and sexual assault at the hands of Mr. Swain. Mr. Swain offers no explanation why the complainant might do such a thing and, of course, he is under no obligation to do so. Nonetheless, the absence of evidence offering some rationale or motivation for the complainant’s conduct in that regard reinforces its improbability.

The accused appealed from conviction, arguing that the trial judge had reversed the onus of proof.  

Absence of Evidence of a Motive to Fabricate:

The Court of Appeal indicated that “a trier of fact is entitled to consider an absence of evidence of motive to fabricate when assessing a complainant’s credibility”, but that there are “certain risks arising from this consideration that must be avoided” (at paragraphs 30 to 33):

Notwithstanding some recent ambiguity in the case law (see e.g., R. v. Cooke, 2020 NSCA 66 at para. 17; R. v. A.S., 2020 ONCA 229 at para. 59; R. v. S.H., 2020 ONCA 34 at para. 11), it has been held that a trier of fact is entitled to consider an absence of evidence of motive to fabricate when assessing a complainant’s credibility…There are, however, certain risks arising from this consideration that must be avoided. These risks are often interrelated.

First, the trier of fact must not equate the mere absence of evidence that a complainant has a motive to fabricate evidence with a proven absence of motive: see Greif at para. 41 and the other authorities referred to in that paragraph. The Crown must meet a high bar to prove an absence of motive to fabricate. For example, evidence that the complainant and the accused had a good relationship is insufficient, without more, to establish that the complainant had no motive to fabricate: Ignacio at para. 33; Bartholomew at para. 25; John at para. 94; L.L. at para. 45. The reason a high standard is required is the recognition that “[p]eople may accuse others of committing a crime for reasons that may never be known, or for no reason at all”…

Second, and for the same reason, the trier of fact must not consider that an absence of evidence of motive to fabricate, or even a proven absence of motive, conclusively establishes that the complainant is telling the truth: R.W.B. at para. 28; Batte at paras. 121, 125; Mirzadegan at para. 14; Stirling at para. 11. In other words, the trier of fact may consider the absence of evidence of a motive to fabricate as one of various factors in assessing the complainant’s credibility and must not place excessive weight on it: R.W.B. at paras. 28, 48; Ignacio at paras. 47–58. In some cases, reliance on an apparent absence of motive to fabricate has been considered appropriate because it was “one of many” or one of “numerous” factors that were present in the court’s assessment of credibility…

Third, the trier of fact must not reverse the burden of proof, which remains on the Crown to prove its case against the accused beyond a reasonable doubt. Specifically, the trier of fact must not look to an accused to explain why a complainant has made the allegations they have or be under any impression that the accused has an onus to demonstrate that the complainant has a motive to fabricate evidence in order to achieve an acquittal: Greif at paras. 39–41; Stewart at para. 26; Batte at para. 121; M.S. at paras. 15–16. Most notably, this issue has arisen where Crown counsel has inappropriately cross‑examined the accused as to why the Crown’s witnesses would fabricate their evidence…

Conclusion:

The Court of Appeal set aside the conviction and ordered a new trial.  The Court of Appeal concluded that the above passage for the trial judge’s reasons “indicate that the trial judge impermissibly shifted the onus to the appellant to explain the complainant’s apparent lack of motive to fabricate. While saying there was no ‘obligation’ on the part of Mr. Swain to provide such an explanation, the judge ‘nonetheless’ considered that his failure to do so weighed against him in the assessment of his credibility’ (at paragraph 50).