MLJ Volume 36-1.pdf - Robson Hall Faculty of Law

The Trial Judge's Four Discretions 173
general standard for exclusion applicable to expert evidence tendered by
the Crown – where prejudice outweighs probative value – to the exercise
of his exclusionary discretion. The Crown took the position that
significant indicia of prejudice, identified by the Supreme Court in
Mohan, 145 namely, its ability to confuse the jury or cause it to put undue
weight on the evidence, were present on the facts. In any event, argued the
Crown, the evidence was not probative to any issue in the case. All told
this meant that the evidence’s prejudicial effect outweighed its probative
value, meriting its exclusion. Barrow J refused to exclude the evidence,
pointing out that the issue of intoxication was relevant to the question of
the accused’s mental state in relation to the offence with which she stood
charged. 146 More important for our purposes, the trial judge held that
prejudicial effect did not “clearly” outweigh probative value so the
discretion was not exercisable. 147
In balancing prejudicial effect against probative value, there is no
doubt that some of the factors considered by the trial judge in exercising
this form of discretion are specific to or figure more predominantly in this
context and are sensitive to the often delicate nature of the evidence in
question. In R v TJB, 148 the accused stood charged with sexual assault and
sought to introduce evidence from three witnesses to demonstrate the
neighborhood’s view on the complainant’s poor reputation for truth and
veracity. Gorman J had to ascertain whether to allow a foundation to be
laid that would then allow the three witnesses to give evidence of the
complainant’s general reputation for truthfulness in the community. The
proper foundation being the witnesses’ actual knowledge of the
community’s view of the reputation of the complainant as to truth and
veracity in the neighborhood in which she resides. Without this
foundation, the evidence would be inadmissible. 149 The danger of
prejudice was clear in that receipt of the evidence might very well lead to
145
Supra note 2.
146
Young, supra note 144 at para 4.
147
Ibid at para 11.
148
Supra note 132.
149
TJB, supra note 132 at para 1. As a general rule, such evidence is inadmissible. In R v
Diu (2000), 49 OR (3d) 40 at 52, 144 CCC (3d) 481 (CA), the Court of Appeal for
Ontario stated: in “general, the character of a victim of a crime is irrelevant and
neither the accused nor the Crown may lead such evidence.”