R. v. Cole, 2021 ONCA 759, October 27, 2021, at paragraphs 82 to 85:
As Binnie J. made clear in Handy, at para. 76, “[t]he principal driver of probative value … is the connectedness (or nexus) that is established between the similar fact evidence and the offences alleged”. Connectedness refers to the logical chain of permissible reasoning that enables the extrinsic evidence to inform the issue the evidence is offered to prove. Therefore, for a proper evaluation of connectedness to occur, the issue that the extrinsic misconduct evidence bears upon must be precisely identified: Luciano, at para. 230.
Evidence of extrinsic misconduct which does no more than “blacken” an accused’s character is inadmissible: Handy, at para. 31. In other words, a chain of reasoning between the extrinsic misconduct evidence and the issue sought to be proved will not be permissible if its relevance depends on the inference that the extrinsic misconduct evidence shows the accused to have the kind of general discreditable disposition or bad character to be capable of committing the offence charged: Handy, at paras. 31-36, 65, and 68. To fortify a conviction by relying on the general inference that ‘the accused is the type of person to commit this kind of offence so they may have done so’ carries the risks of illogically and unfairly disregarding the possibility of rehabilitation, and encouraging the police to “round up the usual suspects”: Handy, at para. 38.
In addition, convicting a person because of the type of individual they are, rather than what they are proved to have done, is contrary to the basic principle that an accused person is presumed innocent unless and until the Crown proves that they have committed the specific offence alleged: Luciano, at para. 219; Handy, at para. 43.
Therefore, if evidence depends solely on a forbidden chain of general reasoning for its connectedness, its probative value will not outweigh its prejudice. Even if the evidence does not depend for its relevance on a forbidden chain of reasoning, the evidence will not be admissible if the probative value of the evidence relating to the permissible inference does not outweigh the prejudicial effect the evidence will have.