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Monday, July 29, 2002

BREAKING NEWz you can UzE...

IAI Conference in Las Vegas next week! It's not too late to register. Visit theiai.org for program and registration information.

Military Works on High-Tech ID's. 29 July, 2002, Future versions of military identification cards will encode information about fingerprints or other physical characteristics, the Pentagon's latest move to tighten security.

Good morning via the "Detail," a weekly e-mail newsletter that greets latent print examiners around the globe every Monday morning. The purpose of the Detail is to help keep you informed of the current state of affairs in the latent print community, to provide an avenue to circulate original fingerprint-related articles, and to announce important events as they happen in our field.

Last week, Steve Scarborough and Ray York introduced a neat concept: The Daubert Card.  We will be following up on their idea in a week or two, after the IAI conference in Las Vegas (next week), and after everyone has had an opportunity to discuss the questions with their co-workers.  If you didn't get a chance to read over the questions or would like to print them out, visit the Detail Archives.

This week, as I prepare for the Daubert presentation Ron Smith and I are giving in Vegas, I realize we never really addressed the "minimum point requirement" issue as it has been brought up in Daubert-type challenges.  Several of the motions to exclude fingerprint evidence have used the argument that since different countries have different point standards, and even further that some countries HAVE NO standard, that demonstrates a lack of standards in the field.  This argument has also been extended to agencies and examiners within the US.

Of course, there is a fundamental flaw in that logic, but if you are not prepared to deal with the issue, it might be difficult to articulate on the stand.  The fact is, you don't just look at points.  In fact, nobody looks JUST at points.  Every examiner I know looks at pattern first, and then points.  Most continue on and consciously look at ridge shape, and the rest do this unconsciously.  The POINT is (ha ha),  we ALL use more detail than just ridge path in any given latent print examination, so we know there is more to a standard of identification than just points.  And this fact itself is agreed upon.  The 1973 IAI resolution, the 1995 Ne'Eurum declaration, and more recently, the SWGFAST QA Guidelines all indicate that no [valid] [scientific] basis [exists] for requiring that a pre-determined [minimum] number of [corresponding] friction ridge [features] (or) [characteristics] must be present in two impressions in order to establish [positive identification] (or) [individualization].

The second part of a foundation to answer this challenge involves ACE-V.  As we covered in earlier Details, ACE-V definitely IS the standard that is used and has always been used by latent print examiners.  Not everyone has always defined what they do with this acronym, but they have always ANALYZED the latent print first, COMPARED the latent to the inked, and EVALUATED the total amount of information they have taken in as they reach a conclusion of identity or non-identity.  That's just the way things have always happened.  So the standard methodology is and has always been ACE-V.

As far as the actual standard of identification itself, it does not rest only on ACE-V and ridge formations.  In reality, the question being asked is "how much do you have to have in order to form an opinion of individualization?"  The question used to be "how many points must you have?" but the answer to that question, of course, is that we don't JUST look at points.  We look at ALL the information that is present.  This includes levels 1, 2, and 3.  To just look at points would be to disregard the other levels of detail present, and that wouldn't be very good scientific practice, now would it?  It can be further explained that both the quantity AND the quality of detail present determines whether an opinion of individualization can result from that particular impression.  This concept can and should be emphasized, because most jurors can relate to a CLEAR image being more valuable than an unclear image, even if it is smaller.  If pressed further on this issue, you can simply explain that the number of matching points has been unitized as a simplistic way to explain to someone that two impressions match, but that it has never been the standard of identification itself.  As latent print examiners, we hold ourselves to a much higher standard than just a number of points.  We have to have 4 elements in order to form an opinion of individualization.  Without all 4 elements, NO latent print examiner ANYWHERE could identify a latent impression.  So how much do you have to have?  I'll tell you exactly what I have to have in order to identify a latent impression:

1:  RIDGE FORMATIONS.  Without them, you can't have an Ident, can you?  Of course, this includes more than points.  Ridge formations include anything that happens in friction ridge skin.  All 3 levels, and other features that occasionally happen: scars, creases, warts, incipient ridges, etc...

2: IN SEQUENCE.  Without it, no ident.  We used to describe this as "relative position," but we realize there is more to sequence than just that concept.  Sequence also involves position along a ridge, direction of opening, angles, all of which are established by visual comparative measurements during the comparison phase of the methodology.  There are other issues involved in sequence, including a thorough analysis to establish sequence of simultaneous impressions. 

3: HAVING DETECTABLE UNIQUENESS.  If the uniqueness does not show up, no ident.  If the uniqueness is not recognized by the examiner, no ident.  We say it this way because all latents are unique.  Even a little smudge will never be exactly reproduced.  The question is, how much of the detail present on the source transferred to the surface we are examining?  That unique detail has to be present, and it has to be sufficient...

4: TO INDIVIDUALIZE.  This is a very high order, and goes above possibly or probably.  When you identify a print, you are saying that no source could have made that impression except the one you are examining.  That is a VERY high standard!

So don't let some defense attorney talk you in to point requirements and the lack of point requirements as being a LOW standard, or even a non-existent standard.  The fact is, we all have to have these elements; and it goes far beyond a simple number of points.  In short, this IS the high standard in the field of friction ridge analysis.  This is the philosophy of identification, and it is our "mission statement" as David Ashbaugh puts it.

So the next time you are asked about the number of points required to make an identification, let that person know that you use MORE than just points, and that you adhere to a very high standard.  But you had better be ready to articulate your position! 

The CLPEX chat board is currently "down."  It says "invalid username" when you attempt to bring it up.  I am currently in communication with Proboards, and if they can't retrieve my data I will set up a new board.  Check back throughout the week; it should be worked out or I will have a new board by the end of the week. (http://www.clpex.com/phpBB/viewforum.php?f=2)

The onin.com forum (http://onin.com/fp/wwwbd/) is also available for more formal latent print-related discussions.


UPDATES on CLPEX.com this week...

No major updates on the site.

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Until next Monday morning, don't work too hard or too little.

Have a GREAT week!


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