Canadian Criminal Evidence/Character/Similar Fact Evidence

General Principles
Similar fact evidence is "presumptively inadmissible. The onus is on the prosecution to satisfy the trial judge on the balance of probabilities that in the context of the particular case the probative value of the evidence in relation to a particular issue outweighs its potential prejudice and thereby justifies its reception."

When assessing the similarities of incidents in a similar fact evidence application, the court should consider:
 * 1) the temporal proximity of the incidents;
 * 2) the physical or spatial proximity of the events;
 * 3) the similarity in detail between the various acts;
 * 4) the number of putatively similar acts;
 * 5) the circumstances surrounding the incidents at issue;
 * 6) distinctive features unifying the incidents; and
 * 7) the occurrence and nature of any intervening events.

The risk of "moral prejudice" refers to risks of the evidence being used to draw a prohibited inference that the accused is the kind of person likely to the commit the offence charged.

The risk of "reasoning prejudice" includes risks such as:
 * The trier of fact may be distracted from deciding the issue in a reasoned way because of the inflammatory nature of the proposed evidence
 * The trier of facts may become confused about what evidence pertains to the crime charged and what evidence relates to the similar fact
 * The trial will begin to focus disproportionately on whether the similar act happened
 * The accused will be unable to respond to the allegation that the similar act occurred because of the passage of time, surprise or the collateral nature of the inquiry

Reasoning and moral prejudice are considered less of a concern for trials by judge alone than trial by jury.

Collusion
Potential inadvertent collusion through rumors and media accounts may occur and should not by itself exclude similar fact evidence. However, such occurrence should go to the weight.

Similarities Between Acts
What would be called "generic similarities" are to be given less consideration. The risk of "relying primarily on generic similarities" to support evidence establishing the actus reus includes the risk that the "initial inference arising from the prior conduct becomes so general, that it approaches bad personhood" and also the risk the accused's "non-specific character, generic similarities may mask underlying dissimilarities that could be important in a particular case."

Case Digests

 * Similar Fact Evidence