Forewarned is forearmed or, if Latin is your thing, “praemonitus, praemunitus”. So the saying goes and clearly there is great value in knowing what lies ahead for us. If we know what is coming our way we can, in theory, prepare properly for any challenge.

Challenges are nothing new to forensic scientists. Critics routinely point out issues with our work. Some of those criticisms are fair and reasonable, others not so much. Much of the critical commentary affects a discipline as a whole demanding an overall, or group, response by members of each discipline. In my experience, disciplines are generally behind the curve in their responses to critics. Nonetheless, over time some issues have been addressed, at least partially if not completely, through empirical research.  Others have not. To be fair, the activities needed to properly address the critics are not trivial and require both time and resources; scarce commodities in modern forensic labs. Overall, things are improving, albeit very slowly.

Criticism takes on a whole new meaning in the context of a court of law. Indeed, I think that criticism is the essence of cross-examination — a fundamental and important aspect of any adversarial justice system. Although essential, it is rarely an enjoyable part of the proceedings for any expert. Read more

R. v. Mohan — Canada’s Daubert

It is safe to say that pretty much everyone working in the forensic sciences has heard of the Daubert ruling or, more specifically, Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).1 It was a pivotal ruling that, together with two subsequent rulings General Electric Co. v Joiner, 522 U.S. 136 (1997)2 and Kumho Tire Co., Ltd. v Carmichael, 526 U.S. 137 (1999),3 has greatly affected many legal jurisdictions in the United States. And, as is often the case, what happens in the USA also tends to have influence elsewhere.

A few years later in Canada there was a key Supreme Court of Canada ruling that addressed admissibility of forensic expertise — R. v. Mohan, [1994] 2 S.C.R. R. v. Mohan — Canada's Daubert 9.4 That is the ruling which laid out the test for the admissibility of ‘novel’ expert evidence (see Mohan, page 4) in Canada. Subsequently, the factors explained in that ruling have been applied, just as those in Daubert were, to many types of traditional forensic science evidence. It is rather ironic that rulings intended to liberalise the admission of new (and potentially) helpful evidence would lead to challenges of all forms and types of evidence.
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