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Monday, May 12, 2003

BREAKING NEWz you can UzE...
compiled by Jon Stimac

Poised to Expand Fingerprinting Capabilities - THE RALEIGH NEWS OBSERVER, NC - May 10, 2003 ...plan would implement a system allowing authorities to fingerprint all misdemeanor offenders and solve more crimes...

Identity Mix-up Clears Utah Man of California Shooting - THE PROVO HERALD, UT - May 9, 2003 ...man who faced extradition in connection with a murder in CA will stay in Utah after officials in both states discovered he isn't the man...

Cross-border Fingerprint Swap Goes High-speed - THE EDMONTON SUN, CANADA - May 7, 2003 ...RCMP and FBI are electronically exchanging fingerprints to stop terrorists or undesirables from setting up shop in Canada or the US...

Detective Says Fingerprint Matched Accused - THE IRISH EXAMINER, IRELAND - May 6, 2003 ...an expert told the court that a fingermark on a paper bag found in a house matched the fingerprint of the accused man...

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.


Derrick Hammond has verified that the Daubert symposium scheduled for June in Las Vegas has been cancelled.  It seems that low registrations were due to general budget problems nationwide.  If anyone has other information regarding Daubert-related events, I would be glad to place it on the Daubert Training page of the website.


From the May 2003 IAI Monthly Update by Joe Polski:

Ottawa IAI Conference Registration

The registration booklets for the Ottawa Conference were mailed late last week. All US mailings were sent by bulk mail and those outside the US by air mail. You should receive that booklet shortly. Please note that the registration form is now available on the IAIís website (theiai.org). The form will need to be downloaded, completed and mailed to the Conference Registrar, Roy Reed. 

Please note that the address shown in the booklet to return the registration is wrong. All conference registration forms should be returned to: 408 Calloway Ave., Sherwood, AR 72120. We are making arrangements with the post office to forward all registrations to the correct address listed above. The application on the website contains the correct address.

The association has received a number of inquiries dealing with the SARS virus in Toronto. The following information is taken from the IAIís website:

The Association has been monitoring the SARS situation daily. At this point, Conference planning continues and there seems to be no reason to consider altering the dates or canceling it. 

SARS appears to be under control in Toronto. There have been no new cases reported in Toronto for the past 22 day, more than double the incubation period. In addition, the World Health Organization (WHO) on April 29th lifted its alert warning for Toronto.

Note that Ottawa is four hours away from Toronto and there have been no SARS cases reported in Ottawa. 

Please also note that most airlines can reach Ottawa without going through Toronto if that is a concern.

Be assured the IAI will continue to monitor events and update this information as needed.

For those of you who plan to attend the IAIís conference in Ottawa this summer, please note that Canada recently tightened up its entry requirements. US citizens need a birth certificate and photo ID in order to gain entry to Canada. If you have a passport, thatís the best identification to use. Visitors from countries other than the US may require a visa for entry. For complete information on entering Canada from the United States, please visit the US State Department website (http://travel.state.gov/canada.html). For complete information about entry requirements from countries other than the United States, please view the Canadian Embassy website (http://canadianembassy.org/immigration/index-en.asp). 


Joe Polski
Chief Operations Officer
International Association for Identification

Last week, Steve Scarborough gave us some of his thoughts on recent / current research in the field of fingerprints.  This week, we take a look at an e-mail I received from a friend and colleague along the lines of:

Hi Kasey! I had a question for you. In the course, I forgot to ask you a question they still ask in court. It was mentioned in class that when you get that "funny fuzzy feeling" inside you know you have an ident. According to the ACE-V method, the final decision is subjective and is reached when sufficient quality and quantity of corresponding Level 1, 2, and 3 friction ridge details are present. The defense attorney's continue to ask "What is sufficient?" Prior to the class I would testify that I needed a minimum of 8 Galton detail points in the same relative position and area. I have seen two impressions from two individuals that had 5 points in the same relative position and area but never have I seen more than 5. Give me some guidance here to be able to answer this question without having to give them a specific number. You and I both know there is no magic number but the "old dog" defense attorneys have a hard time understanding. One asked me the other day that if part of the print was missing, as in a latent, then one could assume that the area that is missing for comparison may have a dissimilarity in it that could rule it a non-ident? Email me as soon as you can, thanks, signed: (friend and colleague) :)

This correspondence actually has several components, so let's take a closer look at each one.

1) What is that "funny" or warm fuzzy feeling, what should we call it, and where does it fit in the ACE-V process?

2) What is sufficient?  and how do we now address this issue without referencing points?

3) What about the missing area?  How do you know there isn't a dissimilarity there?

Who sings?  Do you hum a toon?... say "Gotcha!", "Hooooah", or any one of a number of little releases of that deep down excitement DURING the comparison, before you put your pointers down.  You are at that point in the comparison where you have found your target group, you are side-by-side going ridge by ridge, and at a certain point, BAM... it hits you.  You know.  

As the e-mail said, deep down inside you know it is a match.  you KNOW it.  but you don't stop the comparison there, do you?  Think about it.  At that point, you don't ever stop.  You keep going a little bit more.  You find a couple of more characteristics, or an area of clarity with third level detail... or you run a ridge or two to another area of the print and explore some more.  But you never stop at the first "OOOoooohh".  Why not?  Why do you always find a few more characteristics even though you know deep down it matches?  You know they will be there... IT'S A MATCH!  yet you have to find them anyway.  Why?

That is part of the process.  Your mind is geared toward confirming, or "testing" your tentative conclusion.  You have tentatively concluded that the prints match, and your mind is searching for confirmation of that fact.  This plays directly into the scientific method, immediately before your conclusion is reached.  If you couldn't find anything else to confirm that "warm fuzzy feeling", many would argue you do NOT have a match.  If you got all the way to the point of tentative conclusion and could not find those few more characteristics, then the comparison would be inconclusive.  We don't testify to probable, possible, good chance, very good chance, "I have a warm, fuzzy, feeling it is a match, your honor".  How well would that go over?

No, our conclusions are more than tentative conclusions.  Our reports state that the print WAS made by so-and-so, and the implication is (and should be): to the exclusion of all others.  This is the standard the latent print community chooses to adhere to.  Nothing short of this is an acceptable conclusion.

So how do we articulate what it takes to get to that point?  How much does it take to make an ident?  I always ask my class a couple of questions along those lines.  How much paint does it take to paint a house?  How much fried chicken does it take to feed a redneck?  It depends on the redneck, doesn't it?  (and by the way, I can say that because I AM a redneck!  I have a hound-dog, a rusty pickup-truck, and I shoot guns in my back yard on a regular basis)  But back to the subject... How much paint it takes to paint a house depends on the house!  How much detail or information does it take to identify a print?  It depends on the print.

The major reason is CLARITY.  It takes a sufficient quantity AND quality of information in two images in order for individualization of the unknown image to occur.  If you mention only points, you are disregarding clarity. (see The Detail # 83 for the chart of this concept)  The type and extent of distortion present affects what is necessary for an identification.

So if someone asks you how many points would it take, what they are asking you to do is say how many gallons of paint it would take to paint a house.  Do you know the condition of the house?  Whether it was just painted last year or has never been painted before?  Of course that will affect how much paint it takes.  So will the surface area of the house.  And the paint brush.  And a hundred other things.

The bottom line is that points are only part of the equation.  Sure, they are almost a necessary part of the equation.  And they are a part of the equation that we use quite a bit.  I have heard "points" referred to as the "backbone" of the comparison process.  And perhaps rightly so.  We use this type of detail when it is available.  But it is not the entire equation.

So how do we address the question "how much does it take"?  Ashbaugh states that there are 4 elements in the philosophy of identification:

1) Ridge Formations
2) Sequence
3) Uniqueness
4) Individualization (or exclusion of every other source)
Without any one of these elements, do you have an ident?  No; you have to have them all.  Obviously without ridge formations you don't have a friction ridge print, so you can't have a friction ridge identification.  What about sequence?  

A good example of ridge formations out of sequence appears on page 406 of the Journal of Forensic Identification, Vol 52 No. 4.  Find the bifurcation opening downward that appears 3 ridges below and to the left of the core (at about 7:00) in both the latent and the known print.  Now look at the feature two ridges to the left and down from there.  In one print, you go down and to the left to about 7:30, but in the other print it is more like 8:30.  These characteristics are out of sequence.  Can that be justified?  If there was pressure stretching out the latent print from top to bottom, then perhaps.  However, in our example, the bifurcation directly above our starting point appears CLOSER than in the inked, not farther.  This is in conflict with the distortion we would have to have in order to justify the first area.  Again, these characteristics are out of sequence.

Uniqueness is another major element of the philosophy of identification.  What good are ridge formations in sequence if they are common?  Not as good as if they were rare.  In his book, Ashbaugh mentions "degree of rarity".  Basically, not all features have the same weight on the scale of identity.  Some features hold more individualizing power than other features.  Have you ever been conducting a comparison and saw something really strange in the latent print... and sure enough, exactly in the same position in the known print was that really strange formation?  That would be an example of this concept.  And there has to be a sufficient volume of this "uniqueness" in order to satisfy the fourth and final element:

Individualization.  When we issue a conclusion of identity, we are excluding every other possible source from the equation.  We are saying this print matches beyond any doubt, and to the exclusion of every other finger of every other individual on earth.  Is this a high order?  Sure!!  We are latent print examiners!

Some disciplines use the word "identify" to place an impression in a category or a group.  An example that is often used is that of a footwear examiner identifying an impression as having originated from a Nike, Air Jordan shoe.  They haven't individualized the shoe, they have simply identified that shoe with a particular class or group of shoes.  But in latent prints, we use the word "identify" to express the higher order of "individualization".  This is the fourth and final element of the philosophy of identification for a latent print examiner.

But what about the area that we couldn't see?  Are we sure there wasn't a dissimilarity there?  What if you made an identification in a very small area of high-clarity impression.  You are absolutely sure it is a match, but there just isn't a lot there.  If someone were to ask you how sure you are, you would tell them "absolutely 100%! There is no doubt in my mind this is a positive identification."  So what about the other area?

Do you honestly believe you would find anything different in that area?  Of course not.  No examiner who identifies a print would believe there would be anything different off the edge.  Why not?  Because it MATCHES!, right?  You don't honestly believe there would be a dissimilarity somewhere else, because you know they came from the same source.  You have already identified the print!  If you admit the possibility that something off the edge could be dissimilar, you are admitting that you aren't sure it's a match!  So don't ever let an attorney push you into believing this is a possible scenario.  If you have identified the print, it is an impossible scenario!  It just means you will have to explain to the attorney and/or the jury that you already individualized the print, which means it came from the same source as the known print to the exclusion of every other source.  It would simply be impossible to find a "dissimilarity" in two impressions from the same source.  There might be distortion, but not a true dissimilarity.

And of course, you can always use the analogy that all prints are partial anyway.  Every print we identify is from a source that was not completely reproduced.  Even two fully-rolled know fingerprints have areas near the tip that were not reproduced.  It all comes back to quantity AND quality.  If there is a sufficient quality and quantity of information in both impressions, in sequence, having uniqueness to individualize, then we have a match.  And if we have two impressions from the same source, there is no way we can possibly have a true difference or "dissimilarity" between those two sources.  (except for injury or damage of the source.)

This week's Detail has centered around the question of "how much it takes," but a couple of other issues have allowed us to expand on the question and include some thought-provoking ideas on associated concepts.  I am curious if anyone will discuss the "warm fuzzy feeling" or "individualization versus identification".  If you have any other discussion, or questions / comments about this week's Detail, feel free to visit the CLPEX
message board off the homepage of the website, or at (http://www.clpex.com/phpBB/viewforum.php?f=2)

And as usual, the onin.com forum (http://onin.com/fp/wwwbd/) is also available for more formal latent print-related discussions.

For discussions with an international flair, check out Dave Charlton's forum at: http://charlton97.proboards12.com/index.cgi



"Although the Galton-Henry system had many variants, the most basic observation shows that there is only one main variable- the twist of the lines."


Copied on
3-12-03 by Amanda Taylor.  
Thanks, Amanda!


UPDATES on CLPEX.com this week...

Added several new acquisitions the CLPEX bookstore:

1) Clarence Collins, 1985, "Fingerprint Science" (currently unavailable, but added a link to the new 1994 edition on Amazon)

2) FBI "Classification of Fingerprints" condition: 9+ 1941 edition:
almost perfect except for very lightly bumped corners and light fading to the cover.  No markings, and inside as new!

3) J.A. Larson, Single Fingerprint System, 1924 in excellent condition.

4) Institute of Applied Science correspondence course literature from the 1940's, including all 23 lessons in fingerprints.

Several other books were listed, and I will try to list several more next week.

Feel free to pass The Detail along to other examiners.  This is a free newsletter FOR latent print examiners, BY latent print examiners. There are no copyrights on The Detail, and the website is open for all to visit.

If you have not yet signed up to receive the Weekly Detail in YOUR e-mail inbox, go ahead and join the list now so you don't miss out!  (To join this free e-mail newsletter, send a blank e-mail to: theweeklydetail-subscribe@topica.email-publisher.com )  Members may unsubscribe at any time.  If you have difficulties with the sign-up process or have been inadvertently removed from the list, e-mail me personally at kaseywertheim@aol.com and I will work things out.

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

Have a GREAT week!