Transcript Document

Presented by Robert Carpenter
UCI Undergraduate Research Symposium
May 14, 2005
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Example cases of fingerprint misidentification:
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After serving six years of a 35 year sentence for allegedly
shooting a police officer in 1998, on January 23, 2004 a 33year old (Stephan Cowan), was freed after prosecutors
learned that a fingerprint used in his trial belonged to
someone else.
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After the fingerprint analysis of a detonator bag from the
Madrid train bombings, the FBI announced, “The FBI
lab stands by their conclusion of a 100 percent positive
identification (of American lawyer Brandon Mayfield).”
Within the month a federal court threw out the case against
him. The FBI expressed regret for a fingerprint
identification error that led to his arrest.
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158 people have been EXONERATED and
released from prison after their cases have
been proven by DNA to have been
miscarriages of justice. www.InnocenceProject.org May 1, 2005
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Many of these people were released
from death row.
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How many inmates are imprisoned
because of “mistakes” made during
fingerprint identification?
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When examining the prints of a
subject, how many points are lost in a
latent print as opposed to the points
in the rolled print?
Does the retraining of personnel
increase the quality of processing for
both rolled and latent prints?
When evaluating the points of
identification of a subject’s fingerprints,
there will be fewer than half of the
identification points in the latent print
when compared to those found in the rolled
print.
Retraining personnel will increase the
quality of processing both rolled and latent
prints, creating more points of
identification.
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Belief that fingerprints are unique to each
person dates back thousands of years.
They have been used for over a century to
convict suspects.
They have been used as the ultimate,
indisputable form of identification, without
serious scrutiny of the process.
There has been a lack of standardized
training.
Latent Print
A fingerprint made by deposits of oils
and/or perspiration, not usually visible to the
human eye.
Rolled Print
When the pad of a finger is inked and
rolled on a fingerprint card.
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Campus of the University of
California, Irvine
Chosen for convenience
Researcher access
 Availability of subjects
 Financial considerations
 Availability of the AFIX Tracker Software
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AFIX Tracker
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Gender: Females 366, Males 157
Participants in the subject pool were
volunteers who receive class credit.
Consent forms were signed prior to the
administration of fingerprint processing.
Subjects were briefed at the time of the
experiment to ensure that all rules of
ethical consideration were adhered to.
400
350
300
250
200
150
100
50
0
Female
Male
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Research Assistants were trained at the
beginning of this research project.
They were trained in the techniques used
by law enforcement in the collection of
latent prints.
The methods of rolling fingerprints onto
“ten-print” cards were also taught.
Retraining in these methods was conducted
midway through the research project.
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Subjects entered, read and signed consent forms
and filled out demographic information.
Subjects were informed that their fingerprints
would be protected in a locked university facility.
Subjects were asked to touch two different items.
Subjects then had fingerprints “rolled” at station 2.
Subjects’ fingerprints and consent forms were
logged by student ID numbers.
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Number of rolled prints
collected…5250
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Number of latent prints
collected…1683
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Total number
of prints processed…6933
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All rolled and latent prints were scanned
into the computer utilizing the AFIX Tracker
software.
All fingerprints were subjected to “autoextraction” to identify points of
identification.
Statistical analysis programs were utilized
to answer all pertinent questions.
AFIX Tracker was used to run latent print
searches against the rolled prints obtained
from the subjects.
60
50
40
Rolled
Latent
30
20
10
0
Initial
Retrained
120
100
80
% Of 60
Change
40
20
0
A
B
C
D
E
F
G
H
I
J
Research Assistant Coded Identity
K
L
500
450
400
350
% Of 300
Change 250
200
150
100
50
0
A
B
C
D
E
F
G
H
I
J
K
Research Assistant Coded Identity
L
M N
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Here are examples of accurate and
inaccurate matches made by AFIX.
8 point match
11 point mismatch
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All latent prints were searched against the
corresponding rolled prints from the same
subjects.
30% of the time AFIX was not able to match
to any subject.
Of the “matches” made:
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60% of the matches were to the proper subject.
 40%
of the time it matched to the
WRONG subject.
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These findings mirrored an earlier study.
(Karrie Casada, 2004)
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The use of Live Scan decreases
the error rate among rolled
prints. The technician can see
the quality of print at the
moment and re-roll as needed.
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The increase of identifiable points of latent
prints and the improved proficiency rating
of the research assistants is most likely
attributed to the retraining of the latent
print processing techniques.
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The issue is: Can a fingerprint be linked to
one and only one person?
Additional studies need to be conducted.
Standardized performance criteria for field
officers/investigators who process latent
fingerprints, as well as periodic retraining
sessions.
“Blind” fingerprint examiners, not under the
influence of the police department, should
do the comparative analysis.
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Thank you to those who made this
research possible:
Professor Simon Cole Ph.D.
 Professor Valerie Jenness Ph.D.
 Rachel Dioso Ph.D. Candidate
 Gerhard “Harry” Georgescu
 UROP - Undergraduate Research Opportunities
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Program
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The Phoenix Group, Inc. AFIX Tracker
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The volume and quality of fingerprints collected would not have been possible without the following:
Research Assistants:
Edward Auttapibarn
Stacey Brown
Danielle Campbell
Farah Chaugule
Ana-Maria Comsa
Joy deVera
Adam Dorn
Danielle Evans
Ernest Hu
Jazmin Ibarra
Christine Lee
Wally Liu
Thank you all!
Allyson Maddy
Neha Mahajan
Scott Manese
Chivan Ngo
Marina Ovanessian
James (JB) Robinson
Geoff Ross
Jeremy Takahashi
Bunneat Thap
Ngoc-Suong “Sophie” Vo
Shanshan Yu
Contact Rob Carpenter
Department of Criminology, Law & Society
University of California, Irvine
[email protected]