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

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.

Below you will find a selection of posts that I find particularly interesting, each for its own reason.  I plan to do a mini-review of each of these to explain how they relate to my view of the logical approach to evidence evaluation (among other things).  Unlike DHK it seems to take me forever to write something worthy of posting so please don’t expect anything in the near future.  However, I will add a link to my work as I get them done.  In the meantime I recommend you take a few minutes to review David’s writings, starting with the following: 

Forewarned…

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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2014 ASQDE-ASFDE Panel Discussion “Conclusions…”

The 2014 ASQDEASFDE conference included an interesting panel discussion with the title “Conclusions… Signature and Handwriting Conclusion Terminology and Scales”. I was fortunate to be able to take part, albeit only remotely via Skype.ASQDE ASFDE logos

The abstract for the session was as follows:

A current and global issue in our field is the topic of conclusion terminology and conclusion scales, particularly in respect of signature and handwriting conclusions. It is an important yet difficult topic to address because, while there is some commonality in the conclusion scales used in different geographical regions around the world, within a number of geographical regions there are multiple scales in use. It is for this very reason that it is also a topic in great need of discussion and there is a strong argument that we should attempt to reach a consensus (even if the result is that we agree to disagree).

This panel discussion is a collaboration of insights from numerous colleagues in our field in person, via Skype and in writing from private and government laboratories in geographical regions across the Americas, Australia, Asia, Africa, the Middle East and Europe.
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