In my view, the trial judge was correct in refusing to admit
the proposed opinion evidence of Dr. Harlow.
 The context in which the evidence is tendered for admission, as well as the nature of the evidence itself, are important
factors in any analysis and decision involving the reception of
 It was common ground at trial that the shooter was
the man whom Grant immobilized then released after the man
approached Grant from behind within minutes of the robbery at
Whispers. None of the eyewitnesses to the events identified the
appellant, or anybody else, as that man and thus the shooter.
 To establish the appellant’s identity as the shooter, the
Crown relied on the cumulative force of several pieces of evidence.
The video surveillance evidence coupled with Det. Idsinga’s testimony identifying the appellant as the only person whose image
appeared on the video who shared all the characteristics of the
shooter. In addition, the appellant was at Whispers and the DNA
evidence linked him to Grant.
 Dr. Harlow’s proposed evidence was directed at one of the
several identifiers visible in the video surveillance from outside
Whispers: a white spot visible on the front of the shooter’s shirt.
The Crown submitted that this spot was a reflection of a chain
and medallion around the shooter’s neck, consistent with the
length and size of chain and medallion seized from the appellant
on arrest. Dr. Harlow considered this reflection a possible source
of the white spot, but said it was unlikely because the spot did
not move between two frames 0.133 seconds apart in the video
 At the very least, the proposed evidence failed to satisfy
the necessity requirement at the threshold stage of the admissibility analysis. Fundamental to Dr. Harlow’s opinion were his
observations of the surveillance videos and his conclusion that as
between two frames the white spot did not move. The videos were
available to the jury for their review. No special learning, skill or
expertise was required to determine whether the spot moved
or remained stationary between frames. Items of jewelry such as
that seen here are commonplace in today’s society. Likewise, their
movement with the wearer’s activities. None of this was beyond
the everyday experience of the members of a jury. Nor was it
something about which the jury was unlikely to get right absent
expert opinion from a physicist.
 In addition, as the trial judge pointed out, at least some
aspects of Dr. Harlow’s opinion appeared to extend beyond his
expertise as a physicist. For example, he took measurements of
the appellant’s face, then attempted to transpose them to scenes