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G o o d   M o r n i n g !
Monday, October 18, 2004

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.

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

Border Patrol Expands Fingerprint Searches FCW.COM  - Oct. 7, 2004 ...Patrol agents can now search through two federal fingerprint databases to see if aliens crossing illegally into the US are wanted...

Man Accused in Bombings Sues Government   SALEM STATESMAN, OR  - Oct. 5, 2004 arrested by FBI after his fingerprint was incorrectly matched claims he was singled out because of his faith...

Detainee Fingerprint Ruckus   NEWSDAY, NY - Oct. 5, 2004 ...Police Department illegally printed the majority of people detained during the Republican National Convention...

L.A. Fugitive Apprehended After 13 Years MIAMI HERALD, FL - Oct. 5, 2004 ...Florida fugitive task force members pick up a Pompano Beach man wanted for a 13-year-old murder in California...

Last week
we looked at a link to the Mayfield case and the IAI update.

This week

the Boston Globe reports that the Boston, Massachusetts Police Department will temporarily shut down operations in the latent print section as a result of an audit stemming from the Cowans erroneous identification.

Mark Beck brings us our feature article this week...

A Cautionary Tale for Fingerprint Examiners Re: LiveScan/AFIS
by Mark David Beck, CLPE/CSA

My training and experience are in latent print examination, crime scene investigation, and general investigations as a police detective.  For the past year and a half I have been employed as an AFIS Operator for a relatively small state agency.  In this capacity I have learned a number of things that I believe fingerprint examiners should know but may not be aware of or seriously consider on a regular basis.  One incident in particular has been an enlightening experience for me, and I hope through this article that recent incident will be an “eye opener” for someone who needs it.  I will address five issues in this article, some more obvious than others, but hopefully there is something here for everyone.

While processing livescan criminal arrest submissions, I recognized that there was an identical fingerprint on two separate submissions from one livescan site.  One person was male and one female, coming in within a few minutes of each other.  The #6, “left thumb,” and the left thumb of the simultaneous impressions were of the same finger on both cards.  All other prints on the cards were different.  Because neither person was still in custody and there were no other prints on file for either person, the origin of this “thumb print” is unknown.  How the error occurred, be it operator or system problem is also unknown.

The livescan system did not indicate an error to the operator or on the submitted “card”…as far as it was concerned, the fingerprints were of sufficient clarity and were in sequence.

The AFIS system did not indicate the error for two reasons.  First, one submission was male and the other female.  As it searches by sex first, one could not have hit on the other.  Second, as livescan submissions are processed in batches, neither would have been completed and registered in the system before the other searched.

The reasons the error was discovered were due to what I believe is a somewhat unique set of circumstances.  First, I am an admittedly slow but thorough AFIS Operator who looks at every fingerprint on every card. Second, my experience and training are as a latent examiner and not as a ten print examiner.  I often remember some fingerprints better than some people’s names.  And third, I am privileged to work for an agency that currently allows me to stress quality over production quantity. With a faster operator, a production and volume driven agency depending on scores and the system to indicate errors or in a “lights out” system or “semi lights out” system, this type of error probably would have gone unnoticed.

The fact is, that there are two sets of criminal arrest fingerprint cards with the same “left thumb” print which is of unknown origin.  It is not hard to postulate that given my short time in an AFIS-related work environment and the fact that our agency does not process the volume of submissions that many do, finding one such error indicates that the possibility of finding additional examples of that type of error is quite likely.

Although most likely statistically insignificant, the existence of this type of error is something I did not previously imagine, yet it is something that we should all be aware of.  It is not hard to imagine what the result could have been in this case: a hit to a print on a criminal card that was not that person because one of their file prints was not really theirs.  It is not hard to also imagine a miss on a good latent because a file print on a card or in AFIS is not that person’s and the actual true print is completely missing.  In a situation as the one I am relating, one submission being male and one being female, a search by sex would automatically miss one and the appearance of the print on two different persons’ entries would go undetected.  Even if a “hard card” was obtained, it would still be a print out of the livescan submission and the fact that there is an identical print on another person’s card or to whom the print actually belongs would be unknown.

Although somewhat obvious, it should be recognized that the fingerprints on an arrest card/AFIS entry, do not necessarily belong to the person whose information is on the card.  It is not uncommon through clerical error or false identity claims that the prints and the person are not the same.  Even a simple error such as entering the gender incorrectly will cause a miss if gender is used as a search parameter.

It is not uncommon for a fingerprint to be out of sequence or for one or more fingers to be repeated in two boxes as in the #2 finger being rolled in the #2 and #3 boxes and the #3 finger not being rolled at all. Sequence errors as indicated by livescan stations are so common that they are often overlooked and even over-ridden by operators.  Sequence checking in AFIS systems is often a function that is turned off to speed up processing. You may have a good latent print that misses because a finger did not make it onto the card and therefore not into AFIS.  Likewise, a finger may be out of sequence and in the wrong box; setting a search parameter of the correct finger number would actually cause a miss.

It is also possible for a good quality latent print to miss a good quality known print because of the manner in which the systems plot points.  AFIS systems do not use the same rules that fingerprint examiners are generally taught.  AFIS also sometimes plots so-called “false-minutia”:  incipient ridges, ridge endings along voids left by scars or wrinkles, or bifurcations at large pores.  It may miss pattern type or axis and core.  AFIS systems even occasionally miss good tenprint to good ten print searches because of these reasons and because they can plot different characteristics for submissions of the same person as the appearance can be somewhat different.  Just because your search missed doesn’t mean the correct matching known fingerprint is not in the system.   And just because you’ve registered a latent print in AFIS doesn’t mean that you don’t need to try again at a later date.  Data files may change as new submissions may be substituted for older ones.  AFIS may plot new submissions significantly different that earlier ones and you may in fact plot a new search differently or set new search parameters and be more successful.

Don’t assume a criminal has prints on file or in the system.  Being arrested and booked doesn’t mean that a person was fingerprinted and/or that their fingerprints were entered into the system.  Even if it’s a felony, even if the state involved says there are prints on file…for various reasons, the arrest prints may not exist.  You can’t hit what isn’t there.

A miss does not always mean the criminal has no prints on file or in the system.  The latent print may miss due to quality control issues with the system.

Oh yeah…. and most obvious and yet the cause of a great many misses, a lot of tenprints (inked or livescan) and therefore also AFIS known prints are of worse quality that any latent you will ever declare to be “of value for identification”.

There are many more observations that I have made in this incarnation, and because of them I am a much better and more enlightened examiner…I hope that by sharing this cautionary tale of a spurious “known” fingerprint, that a greater awareness of the potential pitfalls will help other examiners on their latent path through the fingerprint forest.

Good hunting and good Karma.


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