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Accreditation vs. Certification

For a long time now, various groups have recommended that forensic service providers become accredited and/or certified,1,2,3 with accreditation taking a front seat in the discussions.

While these terms have very specific meaning and purpose they are sometimes confused.  I have discussed certification elsewhere but, until now, I have not discussed accreditation, at length.  This post, hopefully, will resolve that and provide my view of these two things.

Each has clear benefits, but there are also some negative aspects.

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Practical Issues when applying the logical approach to FDE work

Applying the logical approach to evidence evaluation in forensic work can be a challenge. I am the first person to admit that is the case. However, I would argue that (1) a challenge is not something to be avoided — it’s something to take on, and (2) the traditional way of doing things is not easy — it too is a challenge. In fact, it is very important to understand that the logical approach is no more difficult or challenging than what has always been done by forensic document examiners. Indeed, in many ways it is simpler and more straight-forward than our ‘traditional’ approach to such things. This post will touch upon some of the practical issues faced by examiners when applying the logical approach to FDE work.

After studying and using this approach for some time I can assure you that it is not a particularly difficult approach to apply. In select aspects it differs from the traditional approach and, as a result, it feels unfamiliar. Often, this relates to the need to consider things more fully; giving consideration to things we tend to ‘quickly assess’ (or dismiss) when using the traditional approach. But it does not change most things that we do. In fact, it primarily affects the evaluation element of the work; not the elements of analysis or comparison. It requires a different way of thinking about the evaluation process which starts with the focus of the evaluation.

The earliest workshops I presented on this topic were focused, for the most part, on the theory and philosophical bases of the approach, plus the benefits of using it. I did not try to delve into the practical side of things, mainly due to time constraints, but also because I was simply trying to convey its value. FDE’s are, however, a practical lot so I feel that my approach has had limited impact. The most common feedback has been, “I can’t see how it will work in practice…”

That is a fair enough criticism, all things considered. More recently, I have been involved in workshops designed expressly for hands-on practice — after all, there really is nothing like hands-on activities to make something real and tangible. More of those workshops are needed, but they are time-consuming to create. For now, here are some thoughts on these issues deriving mainly from feedback received to date during those workshops.

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But doesn’t that mean it is ‘more likely than not’?

When an examiner expresses an opinion along the lines of ‘the findings support one proposition over another proposition’, a question often follows. Specifically, does that opinion mean ‘it is more likely than not that the favoured proposition actually happened’?1 The short answer is “no, it does not mean that.” At least, not necessarily.

In order to reach such a conclusion one must consider information that goes beyond the FDE evidence. As a rule, any opinion I provide will be constrained to the probability of the findings/observations in terms of one of at least two possible explanations.2 Ultimately, equating the two statements is inappropriate because they are not equivalent.3Read more

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Science, experimentation & forensic examination

People sometimes question whether forensic work is scientific in nature. Given that the overall discipline is called ‘forensic science’ this is an interesting, if rather meaningless, question. I say ‘meaningless’ because, practically speaking, it is a non-issue.

Why? Simply because a court may choose to admit anyone as an expert, whether their expertise is scientific, purely experiential, or something else entirely. Nonetheless, it is interesting to consider the issue, if only because forensic document examination is one of those disciplines where this is a common challenge — does it involve any “science” at all?

As a result, this topic is worth some discussion.

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Science vs Pseudoscience

Years ago, in 2013 to be precise, I was invited to speak at the ICA conference held in Montréal, Québec.  The conference had a special session on “distinguishing between science and pseudoscience in forensic acoustics”. Now, I am definitely not an expert in forensic acoustics.  In fact, I know almost nothing about the field other than what I’ve read from time to time. So I wasn’t there to tell the audience anything about forensic acoustics, per se.

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Is Absolute Uniqueness Necessary?

Many years ago I came across an interesting, if limited, discussion in a blog post entitled “Expert testimony in pattern evidence cases – is absolute uniqueness necessary?”1,2 That post is dated Sept 4, 2009, shortly after the publication of National Academy of Science’s report “Strengthening Forensic Science in the United States: a Path Forward”.3 But the basic question posed in it is still relevant today. I would say that most forensic practitioners today would answer the question about the necessity of ‘absolute uniqueness’ in the negative. However, their individual reason(s) for their answer will still vary.

For many people, ‘absolute uniqueness’ is mainly a ‘forbidden’ concept because of some policy they must follow, or because of a more personal recognition of an (often vague) issue relating to the ‘limits of science’. For other people the matter is a well-defined issue in science and logic dictated by the nature and limits of information (knowledge), what information can really tell us about the world, and how information can and should be used to update beliefs about the world. For the latter group (which is steadily increasing in size as awareness and understanding improves), the concept of ‘absolute uniqueness’ is neither required, nor even beneficial in forensic work.

There has been a LOT of discussion about this in recent years, but I found the blog post interesting at the time even though it focused mainly on latent print examination. I feel that not much has changed since then so, even now, it deserves recognition and consideration.  Since the blog itself is no longer active, I have reposted the complete series of messages here (pulling them from archive.org).

The topic started with a post from the moderator (Barry Fisher) who wrote:

Expert testimony in pattern evidence cases – is absolute uniqueness necessary?
What information is needed to form a conclusion about an identification? Do conclusions require statistical data, as in DNA cases, to offer an opinion? Is it possible to state that two items of evidence come from a sole source? What may an expert opine when no statistical data is readily available and only experience suggests a conclusion? The National Academy report raises some profound questions and some intriguing research possibilities. But in the interim, while we wait for academics to study the multitude of pattern evidence forensic scientists encounter in their day to day work, who may report cases and testify in court? Readers are invited to speak to these issues.

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Impinging on the Court’s authority

One of the strangest things I have heard raised in argument against the logical approach is that use of the approach means the expert’s testimony will end up impinging upon the authority of the Court.1 I have heard this a few times recently. I find this particularly troubling because it has come from lawyers. Unfortunately, this has always happened in circumstances where I could not actually discuss the matter with them.

As an objection to the logical approach, this is the most unexpected thing I have ever heard, without a doubt. In reality, proper application of the logical approach is one of the few ways to ensure that this issue will not happen.

To clarify, it is important to first understand the concept of “usurping the role of the Court” which means, in essence, to improperly influence the court’s procedures and decision-making, often by speaking inappropriately to or about the ultimate issue. Or, in other words, to impinge on the Court’s authority to make decisions about the ultimate issue, or ‘what happened’. To be sure, there is a legitimate concern that this could be a problem, particularly when the court is listening to an expert. As a result, the concept has been discussed literally for years and it is not a new concern.

In fact, it can be found in various codes and directives regarding expert evidence. Indeed, Justice Sopinka noted this precise issue in the 1994 R. v. Mohan ruling when he stated, in part, “There is also a concern inherent in the application of this criterion that experts not be permitted to usurp the functions of the trier of fact.” 

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Book announcement: Forensic Document Examination in the 21st Century

FDE in the 21st CenturyI am very pleased to have been contributor to a new textbook, Forensic Document Examination in the 21st Century.  The text was edited by Jan Seaman Kelly and Miriam Angel and will be published by CRC Press.

My personal contribution is chapter 3 entitled “The Logical Approach to Evidence Evaluation”.   The complete list of contributors is impressive and includes Jan Seaman Kelly, Miriam Angel, Brett M.D. Bishop, Rigo Vargas, Mara L. Merlino, Samiah Ibrahim, Lucinda Risi, Lisa M. Hanson, Carolyne Bird, Linda L. Mitchell, Elaine X. Wooton, Donna O. Eisenberg, Thomas W. Vastrick, Marie E. Durina, Kathleen Annunziata Nicolaides, Khody R. Detwiler, Tobin Tanaka, Larry A. Olson, Zain M. Bhaloo, Peter Tytell, Timothy A. Campbell, and Mark T. Goff.  
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Book announcement: Forensic Examination of Signatures

Forensic Examination of Signatures CoverI was pleased be a co-contributor for Dr. Linton A. Mohammed’s latest textbook, Forensic Examination of Signatures.  Other contributors, along with Dr. Mohammed, were Lloyd Cunningham, William Flynn, and Kathleen Nicolaides, with the Foreword by the esteemed Professor David Kaye.  The text was published June 6, 2019 by Elsevier’s Academic Press (ISBN:  978-0-12-813029-2, https://doi.org/10.1016/C2016-0-04445-5).

The book focuses on the forensic examination and evaluation of signatures which is one of the most difficult areas of Forensic Document Examination.  My contribution was Chapter 11 entitled “Conclusions, Reporting and Testimony”, co-written with Dr. Mohammed.
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Human Factors in Forensic Handwriting Examination

EWGHFHE cover

One of the projects I had the pleasure to be involved in was the “Expert Working Group for Human Factors in Handwriting Examination”. The WG was convened in 2015 to conduct a scientific assessment of the effects of Human Factors in Forensic Handwriting Examination, with the support of the National Institute of Justice (NIJ) Office of Investigative and Forensic Sciences (OIFS) and the National Institute of Standards and Technology (NIST) Special Programs Office.

It was a lengthy process involving a lot of people drawn from many different domains. The authors of the report included Melissa K. Taylor, Carolyne Bird, Brett Bishop, Ted Burkes, Michael P. Caligiuri, Bryan Found, Wesley P. Grose, Lauren R. Logan, Kenneth E. Melson, Mara L. Merlino, Larry S. Miller, Linton Mohammed, Jonathan Morris, John Paul Osborn, Nikola Osborne, Brent Ostrum, Christopher P. Saunders, Scott A. Shappell, H. David Sheets, Sargur N. Srihari, Reinoud D. Stoel, Thomas W. Vastrick, Heather E. Waltke, and Emily J. Will.

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