While you are doing the exercises I will pass out by business card.
Latent Fingerprint Individualization
EQUAL JUSTICE UNDER LAW
Objectives of Presentation
The target audience of this presentation, prosecution and defense
teams, hopefully giving them a little better understanding of:
Fingerprint identification process (ACE-V).
Some of the causes of missed and bad identification.
AFIS and latent identifications.
Policies and procedures to insure an accurate result.
FEDERAL RULES OF EVIDENCE RULE 702.
Testimony by Experts
Post-Daubert and Kumho
If scientific, technical or other specialized knowledge will assist the trier of fact to
understand the evidence or to determine a fact in issue, a witness qualified as an
expert by knowledge, skill, experience, training or education, may testify there to
in the form of an opinion or otherwise, provided that (1) the testimony is based
upon sufficient facts or data, (2) the testimony is the product of reliable principles
and methods, and (3) the witness has applied the principles and methods reliably
to the facts of the case.
AMERICAN INSTITUTE OF APPLIED
“The basis of fingerprint identification is the premise that the configurations
formed by the raised ridges of the palmar surface of the hands are unique
and do not undergo any natural changes, except growth, from fetal life until
Minutiae/Points of Identification
What makes the finger unique is the ridge characteristics in each
finger/palm, the average finger has 75 to 150 Ridge characteristics.
The ridge characteristics are the ending ridges, ridges that divide
and converge back into the ridge (enclosure), ridges that divide
(bifurcations). For an examiner to declare an individualization, these
ridge characteristics must appear in the same order on the latent
print and the exemplar. These ridge characteristics are often
referred to as Minutiae or Galton characteristics.
What Constitutes a Good Latent Identification?
How many points are required ?
What is the process used to draw a conclusion ?
Are there standardized policies and procedures?
Training and proficiency required for the examiners ?
Number of Points of Identification to Individualize a
latent to a Known Exemplar
The IAI took a position in August 1973 that quot;No valid basis exists at this time for requiring that a predetermined
minimum number of friction ridge characteristics must be present in two impressions in order to establish positive
This was reinforced in June of 1995 by the Ne'urim declaration in Israel. A conference convened of fingerprint
experts from all over the world. Following the conference a declaration was made quot; there is no scientific basis
requiring a specific number of matching ridge characteristics for a fingerprint identification.
When sufficient minutiae are located in the same true relative sequence or unit relationship, an identification is
made. If a fingerprint examiner identifies a single unexplainable point of dissimilarity between two fingerprint
impressions, an identification between the two fingerprint images cannot be made.
The Identification Procedure Accepted by the World
Fingerprint Community is the Scientific Methodology:
Analysis – the qualitative and quantitative
assessment of Level 1, 2, and 3 details to
determine their proportion, interrelationship
and value to individualize.
Comparison – to examine the attributes
observed during analysis in order to determine
agreement or discrepancies between two
friction ridge impressions.
Evaluation – the cyclical procedure of
comparison between two friction ridge
impressions to effect a decision, i.e., made by
the same friction skin, not made by the same
friction skin, or insufficient detail to form a
Verification/Validation – an independent
analysis, comparison and evaluation by a
second qualified examiner of the friction ridge
Study patterns, points and shapes of ridges.
Focus on a target group of points.
Apply that group to the suspect/elimination print.
Both process’s occur simultaneously:
the same minutiae are present (a bifurcation, ridge ending etc.).
the minutiae flow in the same direction ( the bifurcation is on a ridge running
horizontally and the two divided ridges are to the right of the bifurcation)
the minutiae occupy the same relative positions to each other (i.e. the
bifurcation is separated from an ending ridge by two intervening ridges).
There can be no unexplainable point of dissimilarity between the
two fingerprint impressions
Another equally qualified latent examiner using Analysis, comparison and
evaluation comes to the same conclusion of individualization.
This example has 7 points marked,
would you be comfortable with this?
Latent Image Comparisons
Some identifications are not difficult when the latent image is substantial with good
clarity and the exemplar is a good quality image. Since the introduction of AFIS there
has been a significant number of suspects produced that while not an identification,
contain minutiae very similar to the latent lift image being searched. Since latent
images are often small fragments of the original image and often lack clarity, these
suspect images are challenging fingerprint comparisons. An examiner that only
compares images part time or inexperienced examiners will have a difficult time
making a determination with these more challenging comparisons.
What are the Skill Sets required to be a latent examiner and
how are they acquired?
Of course the basic training courses that everyone takes, usually 1
week long. These courses are followed by more advanced training
Courses which do a good job of giving examiners an understanding of
the identification process. In addition to the training a latent examiner requires
significant fingerprint identification experience in identifying fingerprint impressions.
FBI requires a latent examiner to do 250,000 comparisons before
testifying in court.
Examiners in a state like NY for example, usually work with fingerprints for 10 or
more years before being trained as latent examiners.
This experience identifying fingerprints prior to latent work is crucial.
Scientific research has concluded that it takes eight-to-twelve years of
training for an individual to reach elite levels. This translates to slightly
more than three hours of practice daily for ten years. I believe the 3 hr’s
a day applies to latent Examiners as well, having 10 or more years full
time experience making Fingerprint comparisons is critical in giving the
latent examiner the skill sets needed for today's complex AFIS
Many state and local agencies can’t justify the costs for training or for a full time
latent fingerprint examiner. A situation that increases the likelihood of an error.
What are some of the Ramifications of Erroneous
Individuals wrongly convicted
Dennis Fritz in 1988, in Pontotoc County, Oklahoma, was sentenced to life in
prison for a1982 murder. Five years after the murder an incorrect analysis of
Gene Bibbins 15+ yr’s, fingerprints from the crime scene were inconclusive,
and that the analyst had checked those findings with the state crime lab. In
fact, Bibbins was excluded as the source of the fingerprints, in a state crime
While Erroneous Identifications get the most
Headlines, Missed Identifications can have a
significant impact a Court Case
If the print is missed an individual essential to the case may not be identified. This could deprive
investigators of information/evidence critical to a case. Whether prosecution or defense some of the
questions that should be asked:
Did the case have unidentified latent fingerprints and how many times was it searched in AFIS ?
Latent search is 85% accurate when both images have 15 points of identification on both the search
and target print. Accuracy goes down when fewer points are available.
Agency AFIS search procedures ?
Did the search produce a strong suspect and was it evaluated by only 1 examiner, should a 2nd.
qualified latent examiner have evaluated the print. Was the print searched just locally or
Were any of these fingerprint comparisons considered inconclusive by an examiner(s)?
While misses are often regarded as less serious than bad identifications, the results of a missed or
bad identification can both lead to a loss of life in extreme cases.
Forensic Biometric Identification Solutions (FBIS).
In today's world, FBIS’s services
are available to agencies and
Can provide services to evaluate:
individuals across the country.
Most if not all comparison work
Training and experience of the latent fingerprint examiners.
can be evaluated electronically,
Policies and procedures used by the agency.
by CD or mail.
On the current examination did the 2nd. Examiner know the
conclusion of the 1st. Examiner before making a
determination or was it a blind validation.
Did any examiners examine this identification and not
individualize the latent to the exemplar.
Is a court exhibit available with good quality images.
Proficiency test results and the procedure used to
administer the testing.
Either examiner ever been involved in an incorrect
Feel free to contact us by phone or e-mail for more information.