There is zero tolerance for friction ridge identification error in forensic science.
Ignoring standards causes errors. A minimum number of Galton detail "points" does NOT equal an identification standard. The standard for identification is not a number.
As demonstrated below,
relying on a specific number of allegedly
matching "points" can be a formula for disaster. The misleading comfort
of a "number" can lead Examiners (and Police administrators) to ignore more
important factors which insure reliability.
Since the mid-1970's the International Association for Identification (IAI) and its Latent Print Certification Board have worked with state and regional chartered IAI Divisions throughout the U.S. toward the goal of improving professional abilities. Since 1995 the Federal Bureau of Investigation has sponsored the Scientific Working Group on Friction Ridge Analysis, Study and Technology (SWGFAST) for developing consensus standards which preserve and improve the quality of service provided by the latent print community nationwide.
During 1995 through 1997 American Latent Print Examiners established minimum qualification, training and quality assurance SWGFAST guidelines through review, discussion and feedback at local and national meetings, and through peer review in professional journals.
Latent Print Examiners are able to reliably make positive identifications:
1. With appropriate training (SWGFAST training content guidelines);
Analysis – the qualitative and quantitative assessment of Level 1, 2 and 3 details to determine their proportion, interrelationship and value to individualize.
Friction ridge identification reliability is insured by Training, Experience and Ability coupled with ACE-V to effect a positive identification when sufficient quality (clarity) and quantity of corresponding Level 1, 2 and 3 detail exists. Quality (clarity) and quantity vary with each friction ridge impression.
Analysis is objective.
Comparison uses objective observations.
The final identification decision is subjective and is reached when sufficient quality (clarity) and quantity of corresponding Level 1, 2 and 3 friction ridge details are present.
The quality (clarity) and quantity of details necessary to effect the identification can vary based on training, experience and ability of the Latent Print Examiner.
Even though each latent print can have different quality (clarity) and quantity of Level 1, 2 and 3 details... Latent Print Examiners with similar training, experience and ability should be able to identify the same latent and inked prints.
Quality assurance and quality control guidelines exist to detect erroneous friction ridge impression identifications. The Examiner making the error is immediately suspended from casework activity. Remedies to insure operational reliability include the following:
David Ashbaugh's important Ridgeology publication defines Level 1, 2 and 3 details and explains in plain language the scientific methodology called ACE-V in use by Latent Print Examiners worldwide.
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Error Rate for Friction Skin Identifications is ZERO
If you are a Latent Print Examiner, you know the above statement to be true. If you are an attorney, police administrator or other non-expert, this may sound unrealistically strict. Scientists generally concur that a reliability of 95% constitutes scientific certainty (1), (2). In many areas of science and many professions, such reliability serves society well. For example, the acceptable error rate for Chicken Sexers (persons who examine the backsides of one-day-old chicks to sort males from females) is between 2.3 and 5 percent when examining 700 to 800 chicks per hour.
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|Third Case - another problem identification
from the same EU Laboratory as above.
Click here for details about this case and the resulting inquiry, and government laboratory quality control/quality assurance improvements.
presented above are much sharper than
charted images used in court with this "identification."
You can see the dots of the "coach scene" background pattern in the latent
print photos on this page, versus the blurred court chart images of the
|As an expert working in fingerprints since 1971, I have seen some
of the skeletons in my discipline's closet. In the below paragraphs
you can read my personal reasons for building this page. --Ed German
In 1984, a friend of mine (a Latent Print Examiner in the Midwest) brought me the charts shown above in the "first case" (a burglary investigation). That same day I (and coworker Steve Kasarsky) caused an incarcerated prisoner to be freed and charges dropped because we pointed out the error. The wrongfully incarcerated prisoner was on parole from prison. The Latent Print Examiner, being relatively new in the business, had not previously caused anyone's incarceration based upon fingerprint evidence (the chart represents his first latent print "identification" that resulted in a warrant issued for an arrest) and the Prosecutor decided that no future warrants would be issued based on just the local examiner's work. The "first case" Latent Print Examiner was decertified and continued working as a policeman and crime scene technician (not as a Latent Print Examiner issuing identification reports). He is still employed by the same agency and to my knowledge has since always submitted potential fingerprint identifications to outside agencies for expert examination. I do not reveal the city or state here because I am proud of his (and his department's) integrity and professionalism.
Note: The below 1987 incident is in no way a reference
to any Latent Print Examiners currently working in North Carolina (the persons
involved are no longer employed by any law enforcement agency at all to
my knowledge). The City/County Bureau of Identification which employed
the below Latent Print Examiners no longer exists. Both the Cumberland
County Sheriff's Department and Fayetteville City Police Department have
advanced tremendously in the past two decades, incorporating modern procedures
and guidelines (IAI, SWGFAST, etc.) in all areas of Latent Print Examination.
In 1987, a Latent Print Examiner with
a City/County Bureau of Identification in
Carolina, brought me a crime scene mark (latent fingerprint) for "computer
enhancement" because he was having trouble charting it. I told Trogden
that no enhancement in the world would ever change the fact that the print
was not made by the suspect. The Examiner said he wanted a second opinion
and I sent him immediately to Marty Ludas in Raleigh, North Carolina who
also told the Examiner it was a "bum ident." On the morning jury selection
commenced for the trial, the Prosecutor related to Defense and the court that
he had recently learned that although there was enough similarity in the
latent print to make a tentative identification, it was NOT a positive identification.
This was a ludicrous remark (tentative identification upon which to base
arrest), one I have never heard since. The charges were dropped on
the spot and the defendant (who had been jailed for 13 months primarily based
on the identification) was immediately released.
When I learned of the sequence of events, I contacted the Prosecutor and Chief of Detectives in North Carolina to relate that the error had been revealed two weeks earlier and was not even "close" to being an identification. Also, because the erroneous "expert" was self-trained and was the trainer for the only other "expert" in his office (the blind leading the blind regarding expertise), I urged the Chief of Detectives to have 100% of all their prior casework reviewed by outside experts. The local police balked at my suggestion and told me their experts said it was a once in a lifetime error and I was just attacking them because they refused to participate in the IAI's certification testing program.
I continued to assert that where there is smoke, there is fire. After several calls and formal letters to the local police and Prosecutor, I finally "won" and it was decided that no new warrants would be issued based on the North Carolina examiner's reports until completion of an outside review of all their casework. The North Carolina state crime lab declined to participate, but Robert Hazen, Senior Expert at the FBI's Latent Fingerprint Section, agreed to supervise the 100% review by his office's experts. The review revealed a number of serious errors, including erroneous fingerprint identifications involving co-suspects as well as "elimination" prints... and also revealed that valid identifications against suspects in serious crimes had been missed. Nobody else was freed from jail, but I still felt vindicated from the claims I was persecuting the two "experts." The last I heard, both experts had left the agency and the senior of the two was teaching Criminal Justice at a college.
I know that fingerprint (latent print examination) experts perform an invaluable service to society. I also believe that quality control/assurance and other checks and balances such as international peer review must exist to insure the discipline's reliability.
In the "first case," the wrongfully accused was immediately released. In the North Carolina case, I have always regretted that the defendant spent an additional two weeks in jail because I trusted the system to notify Defense and the court immediately.
If you are an expert and have knowledge of an erroneous identification impacting a person's liberty or reputation you must "do what has to be done" to inform the investigators in charge of the case... and verify timely notification to the Prosecutor and/or Defense/Court.
If you are an expert and have additional examples of erroneous identifications you think might benefit the discipline through Internet posting, please e-mail me.
--Ed German, CLPE,
|The webservant desires to assure readers
that the content herein does not purport to represent the position or opinion
of the US Government, US Department of Defense, US Army, US Army Criminal
Investigation Command, Intelligence Division of the HQ, US Army Criminal
Investigation Command, FBI, SWGFAST, ASCLD/LAB, or any other entity or organization
with which the webservant was or is affiliated.