Evidence
- Week 2 Notes: Relevancy, Probative Value, and Prejudicial Effect
R v Watson
(1996, SCC)
Facts
: Watson charged with murder; Hedley and Caine dropped off at victim's workplace. Crown's theory
is that it's a pre-planned hit where Watson was lookout. Defence believes there was a spontaneous
dispute. One expert testified that victim always carried a gun, but Crown objects to relevancy.
Issue
: Whether the evidence of the expert is admissible in court.
Rules
: Relevance must be assessed in the context of the entire case and respective positions taken by
Crown and the defence (
Sims
)
Probative Value
: There is no minimum probative value for evidence to be deemed relevant.
Relevance doesn't involve considerations of sufficiency of probative value (
Morris
)
o
Admissibility
: No exclusionary rules in criminal cases where otherwise relevant evidence is
suggests that party is has bad character (
Arcangioli
); trial judge must determine whether it
will significantly prejudice jury
o
Prejudice
: An improper use or effect of evidence - commonly, the possibility that evidence
might be used to support impermissible inferences
Relevance
: As per
Morris
, relevance requires a determination as to whether as a matter of human
experience and logic Fact A makes Fact B more probable than without Fact A.
o
If it does, then Fact A is relevant to Face B; hence, if Fact B is relevant in itself, then Fact A is
prima facie
admissible
o
Materiality
: A fact is immaterial if it relates to an issue that is of no consequence to the
litigation nor of no moment to the outcome in the case (
Elliot
;
Quiznos
)
Circumstantial Evidence
: (1)
Evidence of Habit
- involves an inference of conduct on given occasion
based on established pattern of past conduct (i.e., reliable predictor of actions)
o
(2)
Evidence of Disposition
- involves inference of the existence of a state of mind from a
person's conduct based on other occasions (i.e., reliable predictor conducts in each
situation)
Application
: Witness's evidence that deceased carried gun suggests repeated and specific conduct, and
inference from possession of gun is relevant to issue at trial.
Admissibility
: Proposed evidence had significant value for defence on question of whether deceased
was armed at relevant time.
Conclusion
: Trial judge erred in holding evidence was inadmissible. Evidence of habits is relevant to
person's behavior on occasion. Chain of inferences are acceptable.
Probative Value and Prejudicial Effects
Prejudicial Effects
: Trial judge's estimate of how likely the jury, even if properly instructed, will use the
evidence for improper purposes or the detrimental effect of the evidence on other aspects of the
process
Most characteristic type is the possibility that evidence, although relevant an in principle admissible
to support one kind of inference, might be used to support an impermissible inference
Forms of Prejudice
: Danger that evidence (1) will arouse jury's emotions of prejudice, hostility, or
sympathy; (2) create a side issue that unduly distracts jury; (3) consume an undue amount of time;