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

The Trial Judge's Four Discretions 145
admissibility mentioned here, is exclusionary in nature. 9 In other words, to
be ultimately received, evidence has to simultaneously avoid being
excluded under the rules of relevance and materiality, under specific
exclusionary rules like the hearsay rule, and under the trial judge’s residual
discretion.
The exclusionary discretion power is significant “as it has the
theoretical potential to render all other rules of evidence obsolete and to
undermine the role of the trier of fact.” 10 Reliability of evidence has
traditionally been evaluated narrowly for the purpose of admissibility. It
was only tested to the extent it fell under a specific exclusionary rule. The
prevailing justification for this was that assessing reliability of evidence
relates to weight, and questions of weight are for the trier of fact, who will
be better positioned at the end of the case to assess weight in light of all
received evidence. In other words, trial judges acting as triers of law were
to restrict themselves to questions of admissibility. 11 However, with the
emergence and expansion of a judicial discretion to exclude, a judge who
chooses to exclude evidence is doing so based on an assessment of its
reliability. In other words, he or she is weighing the evidence, albeit in a
much more restrictive way than a trier of fact.
Previous literature has held that there are two general types of
exclusionary discretion: that which exists at common law (which permits
technically admissible Crown evidence to be excluded where its prejudicial
effect outweighs its probative value) and that which exists by virtue of the
Charter 12 and by the Supreme Court of Canada’s decision in R v Harrer 13
(which permits technically admissible Crown evidence to be excluded
9
R v Dawson (1997), 44 CRR (2d) 359 at 369 (available on WL Can) (OCJ Gen Div).
10
Paciocco & Stuesser, supra note 1 at 44. See also R v Duguay, 2007 NBCA 65 at para
54, 320 NBR (2d) 104, for an appellate court’s recognition of this. While Paciocco
and Stuesser here are speaking of a specific form of exclusionary discretion possessed
(namely, the general discretion at common law to exclude Crown evidence where its
prejudicial effect outweighs its probative value), the statement is equally applicable to
the trial judge’s exclusionary power more broadly.
11
Peter K McWilliams et al, Canadian Criminal Evidence, looseleaf (Aurora: Canada Law
Book, 2008) at 5-10 [McWilliams et al].
12
Charter, supra note 4.
13
[1995] 3 SCR 562, 128 DLR (4th) 98, [Harrer cited to SCR].