Evidence - 'Propensity Reasoning'. R. v. Jahangiri
In R. v. Jahangiri (Ont CA, 2022) the Court of Appeal considered 'propensity reasoning', which appears to be a recent term for character or similar fact evidence:
 Evidence that takes its probative effect from propensity reasoning is presumptively inadmissible, although relevant. The presumption is rebutted when the Crown, on a balance of probabilities, proves that the probative value of the evidence outweighs its prejudicial effect: R. v. Handy, 2002 SCC 56,  2 S.C.R. 908, at para. 55.
 Doherty J.A. explained in R. v. Batte (2000), 2000 CanLII 5751 (ON CA), 49 O.R. (3d) 321 (C.A.), that propensity reasoning involves two inferences: first, one infers from conduct on occasions other than the occasion in issue, that a person has a certain disposition; and second, one infers from the existence of that disposition that a person acted in a certain way on the occasion in issue: “Viewed in this way, the evidence of the accused’s discreditable conduct is a form of circumstantial evidence and meets the legal relevance criterion”: at para. 97.
 The reasons for exclusion of discreditable conduct evidence were described by Doherty J.A. in Batte, at paras. 99 and 100, as follows:
Even where the discreditable conduct is such as to reasonably permit the inferences necessary to give propensity reasoning probative value, that evidence can still be misused by the jury. Often, evidence which can support propensity reasoning will have a much greater potential to improperly prejudice the jury against the accused. As Sopinka J. observed in R. v. D.(L.E.), 1989 CanLII 74 (SCC),  2 S.C.R. 111 at 127-28, a jury may assume from the evidence of discreditable conduct that the accused is a bad person and convict on that basis, or they may convict in order to punish the accused for the discreditable conduct, or they may become embroiled in a determination of whether the accused committed the alleged discreditable acts and lose sight of the real question – did he commit the acts alleged in the indictment?... In R. v. B.(L.), Charron J.A. referred to the “forbidden line of reasoning” in respect of discreditable conduct evidence as “that which leads to the conclusion that the accused committed the offence with which he is charged based, not on the strength of the evidence which has a connection to the issues in the case, but rather, on the strength of the evidence that he is ‘a bad person’ who would have a tendency to commit this offence”: at para. 48. She stated, at para. 43, that the relevance of this kind of evidence “usually depends on the proposition that persons tend to act consistently with their character, or, in other words, that persons have the propensity to act in the manner in which they have acted previously. This underlying proposition is all about propensity” (emphasis added).
Propensity reasoning also imperils the overall fairness of the criminal trial process. It is a fundamental tenet of our criminal justice system that persons are charged and tried based on specific allegations of misconduct. If an accused is to be convicted, it must be because the Crown has proved that allegation beyond a reasonable doubt and not because of the way the accused has lived the rest of his or her life. An accused must be tried for what he or she did and not for who he or she is….
 Contrary to the appellant’s submission, the probative force of the cash seizure evidence did not depend on propensity reasoning, and therefore cannot be properly considered discreditable conduct evidence.
 In a recent decision, R. v. Baksh, 2022 ONCA 481, this court was dealing with what was alleged to have been cross-count similar act evidence in a drug trafficking case where the only issue was the identity of the trafficker. The appellant argued that the trial judge was not permitted to rely on similar act evidence – evidence by an undercover officer that he had purchased cocaine from the same person on all four occasions − without first conducting an inquiry pursuant to r. 30 of the Criminal Proceedings Rules. At para. 23, Favreau J.A. identified as the “threshold issue”, whether the evidence the trial judge relied on across the four drug trafficking counts was properly characterized as similar act evidence (and therefore presumptively inadmissible). In concluding that it was not, she observed that, while the trial judge relied on some of the same evidence across the different counts, “he did not do so for the purpose of embarking on impermissible propensity reasoning … that, because the appellant was the drug trafficker on one occasion, he was more likely to be the drug trafficker on other occasions”: at para. 24. She explained at para. 26:
Not all instances of reliance on evidence across counts amounts to impermissible similar act evidence or evidence that raises a risk of propensity reasoning: see e.g., R. v. Settle, 2021 ABCA 221, at paras. 34-36; R. v. Giesbrecht, 2019 MBCA 35, 373 C.C.C. (3d) 70, at paras. 73-77. Whether the evidence is properly characterized as similar act evidence depends on the use to which the evidence is put: see e.g. R. v. Graham, 2015 ONCA 113, 330 O.A.C. 394, at paras. 29, 33; R. v. deKock, 2009 ABCA 225, 454 A.R. 102, at para. 36.