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

6 MANITOBA LAW JOURNAL|VOLUME 36 ISSUE 1
placed considerable emphasis on hair microscopy. The RCMP alone
maintained a staff of approximately 35 hair examiners across Canada. 9 But
it was just a tool: hair comparisons were simply intended to provide a
“class association”; that is, as the National Research Council of the
National Academies put it in 2009:
a conclusion of a “match” means only that the hair could have come from any
person whose hair exhibited—within some levels of measurement uncertainties—
the same microscopic characteristics, but it cannot uniquely identify one person.
However, this information might be sufficiently useful to “narrow the pool” by
excluding certain persons as sources of the hair. 10
So it was fundamentally an investigative tool intended to “narrow the
pool” of suspects. Despite this, prosecution services sometimes used the
results of the comparison as evidence in criminal prosecutions. Hair
microscopy faded from prominence during the early to mid-1990s (at least
on the court side) with the advent of DNA technology.
For reasons I will now examine, hair microscopy probably yielded
nothing more than an educated guess. 11 Its probative value was slight, the
prejudicial effect on the conduct of the trial was significant, and its use
ought to have been confined to investigations and not extended into the
courtroom. 12
9
Report of the Commission of Inquiry Into Certain Aspects of the Trial and Conviction of James
Driskell, (Winnipeg: Government of Manitoba, 2007) (The Honourable Patrick J
Lesage, QC), at 174, online: [Driskell Report].
10
NRC, supra note 6 at 156.
11
To adopt the phrase used consistently (albeit in a different context) in the following
appellate decisions: R v Ranger (2003), 67 OR (3d) 1 at para 82, 178 CCC (3d) 375
(CA); R v Clark (2004), 69 OR (3d) 321 at para 78-79, 182 CCC (3d) (CA); R v
Klymchuk (2005), 203 CCC (3d) 341 at paras 33-37 (available on WL Can) (Ont CA)
[Klymchuk].
12
Even if the test for admissibility of expert evidence is met, a trial judge may reject the
proffered evidence if its prejudicial effect on the conduct of the trial outweighs its
probative value: R v DD, 2000 SCC 43 at para 11, [2000] 2 SCR 275. I will turn to
this later on in this section, but the Ontario Court of Appeal has powerfully observed
that items of evidence amounting to nothing more than an ‘educated guess’ “… can
play a valuable role in the investigation of crime by directing the police to fruitful
areas of investigation. They cannot, however, be admitted as evidence under the guise
of expert opinion”: Klymchuk, supra note 11 at para 37.