CSFS Position paper on the Logical Approach

I recently published an editorial in the Journal of the Canadian Society of Forensic Science.  Two versions were published almost simultaneously (the original written in English and a translation in French) entitled, respectively, “CSFS Document Section Position on the Logical Approach to Evidence Evaluation and Corresponding Wording of Conclusions” and “La position de la Section des documents de la SCSJ sur l’approche logique de l’évaluation de la preuve et le libellé des conclusions”.

I wrote these in my capacity as the sitting chairman of the Documents section of the CSFS, on behalf of the members of that section.  The impetus for writing them was to introduce the “logical approach” and related topics to the Canadian forensic community in a ‘formal’ way (hopefully resulting in ongoing discussion) and to provide the public and the courts with the perspective of forensic practitioners who have reviewed the literature and studied this issue in depth. To that end, the document references many initiatives relating to the topic. I will note that it’s not a perfect document but it covers the main points reasonably well.

Please note that this position paper was first written a few years ago.  There was considerable delay in publication relating to the production of an acceptable French-language translation of the document. I must thank Julie Binette who was invaluable in that process. The delay, however, means the references provided in the paper are not fully up-to-date with the very latest developments in this area.

Nonetheless, that shortcoming doesn’t detract from the position expressed.  Today there is even more support and justification than is outlined in the paper. 

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David H. Kaye’s “Forensic Science, Statistics & the Law” Blog

David H. Kaye (DHK) is one of my favourite writers. He is truly prolific and always manages to provide great insights for the reader. His grasp of statistics, logic, and the law is second-to-none, and his ability to communicate those very challenging topics to his audience is equally impressive.

As a mini introduction, David “…is Distinguished Professor, and Weiss Family Scholar in the School of Law, a graduate faculty member of Penn State’s Forensic Science Program, and a Regents’ Professor Emeritus, ASU.” If you would like to see a list of his publications check out http://personal.psu.edu/dhk3/cv/cv_pubs.html 

Yes, DHK has written many things on many topics.1  But I would like to focus on his less formal writings from his blog  Forensic Science, Statistics & the Law.

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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

The ‘best’ textbook ever written about forensic handwriting identification…

Okay, determining the ‘best’ of anything is always a challenge. It is, in almost every instance, a highly subjective decision based on some set of appealing features or characteristics… appealing to the person making the determination, of course. And, because this is my blog, that person happens to be me.

In fairness, there are a number of authors who have written extensively on the topic: Osborn, Ellen, Hilton, Harrison, Hilton, among others (and I apologize to those I have left off this list). I have read all of those textbooks (including most editions) and each has its strengths and weaknesses.

Nonetheless, in my opinion the best general textbook written to date on the topic of handwriting identification was done by co-authors Roy A. Huber and A.M. (Tom) Headrick, both long-time document examiners in the R.C.M. Police laboratory system.

That textbook is Handwriting Identification: Facts and Fundamentals.1

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Can of worms…

When someone “opens a can of worms” it usually spells trouble. Worms in a canFor many people, that phrase evokes a powerful image of a writhing mess of worms escaping from a previously-sealed, but now opened, can or container. With the result of such action being serious problems for the owner of said can, often problems of an unanticipated or uncertain nature. In the context of our work as Forensic Document Examiners I sometimes hear this in discussions of how to handle questions on the stand. The advice goes along the lines of ‘keep your answers simple and say as little as possible in order to limit any opportunity for questions from the other side.’

It is suggested that lengthy or complex answers will only lead to more questions and more discussion. The latter are the proverbial “can of worms” that one must strive to avoid opening.

That makes little sense to me.
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