Relevance, materiality and admissibility

R. v. Luciano, 2011 ONCA 89, a rather nasty double murder case released this week, has a useful passage regarding relevance, materiality and admissibility:

Relevance

[204] Relevance is not an inherent characteristic of any item of evidence. Relevance exists as a relation between an item of evidence proposed for admission and a proposition of fact that the proponent seeks to establish by its introduction. Relevance is a matter of everyday experience and common sense. Attaching a label like "evidence of after-the-fact conduct" or "post-offence conduct" to an item of evidence does not establish its relevance. An item of evidence is relevant if it renders the fact it seeks to establish slightly more or less probable than it (the fact) would be without the evidence, through the application of everyday experience and common sense.

[205] We assess the relevance of items of evidence in the context of the entire case and the positions of counsel. Relevance does not exist in the abstract or in the air: R. v. Cloutier, [1979] 2 S.C.R. 709, at pp. 730-32. An item of evidence does not cease to be relevant or become irrelevant because it can support more than one inference: R. v. Underwood (2002), 170 C.C.C. (3d) 500 (Alta. C.A.), at para. 25.

[206] To be relevant, an item of evidence need not prove conclusively the proposition of fact for which it is offered, or even make that proposition of fact more probable than not. What is essential is that the item of evidence must reasonably show, by the application of everyday experience and common sense that the fact is slightly more probable with the evidence than it would be without it: 1 McCormick on Evidence (6^th ed.), para. 185, at p. 733.

Materiality

[207] To make its way into a criminal trial, an item of evidence must also be material. Evidence is material if what it is offered to prove or disprove is a fact in issue. What is in issue is determined by and a function of the allegations contained in the indictment and the governing procedural and substantive law. If the fact the evidence is offered to prove is not in issue, for example because of an admission, the evidence is immaterial: Candir at para. 49.

[208] In a prosecution for unlawful homicide charged as murder, evidence that tended to show the identity of the killer and the killer's state of mind contemporaneous with the killing would be material.

Admissibility

[209] Admissibility is a legal concept. Its rules, which are negative and exclusionary, are rooted in policy considerations we regard as of sufficient importance to justify the exclusion of relevant and material evidence. No single policy underlies every admissibility rule. Sometimes, an admissibility rule is animated by concerns about the reliability of evidence. In other instances, a rule may attempt to curb a prohibited chain of reasoning.

[210] Admissibility rules are not unyielding. They give ground, admitting evidence by exception. What justifies exceptional admission varies from one admissibility rule to another, but is generally linked to the policy that underpins the rule of exclusion.