Breaking NEWz you can UzE...
compiled by Jon Stimac
The CSI Effect –
US NEWS.COM - April 25,
2005 ...on TV, it's all
slam-dunk evidence and quick convictions. Now juries expect the same
thing--and that's a big problem...
Patient Process of Fingerprinting Yields Rich Rewards of Evidence
– AUBURN JOURNAL,
CA - April 24, 2005
...fingerprints left behind at the scene of a crime
could lead investigators right to the culprit who inadvertently left
Wendy's Recovering from Finger Hoax –
NEW YORK TIMES, NY - April 23, 2005
...the 'victim' has since been
arrested, and police believe the incident was a hoax....
Does the FBI Have Your Fingerprints? –
SLATE - April 22, 2005
...perhaps, if your one of the following: criminal, suspected
criminal, government employee, military personnel, and a few
Last week, we took a look at the Human Identification 2005 e-symposium
from the week before. The fingerprint related presentations are now
archived and can be listened to at any time by visiting the website,
registering, and accessing them at your leisure:
This week we look at the publication of recent information regarding the
fundamental difference between experts and non-experts by Dr. Tom Busey of
Indiana University and John Vanderkolk, Indiana State Police.
Fingerprint study offers clues to how expert minds
By Bethany Nolan, H-T Staff Writer
April 18, 2005
They’re the staple of every television crime show — the earnest expert who
testifies the suspect’s fingerprints match those found at the scene.
While such experts exist in real life, do they really know more about
fingerprints than the rest of us?
Yes, says Tom Busey, an associate professor of psychology and cognitive science
at Indiana University.
Busey and John Vanderkolk — a veteran fingerprint examiner and laboratory
manager for the Indiana State Police at Fort Wayne — have completed a study that
shows experts’ brains work differently than those of non-experts when confronted
with two prints to examine.
Vanderkolk said the idea for such a study came to him after he learned of a
federal judge who’d ordered a prosecutor to show the fingerprints gathered in a
case to the jury, and let them decide whether the prints proved the suspect was
at the scene.
While the judge later reversed his decision, Vanderkolk was searching for some
way to prove experts are truly experts. “Then, we had no ammunition to show
we’re different,” he said. “Now we do.”
He contacted Indiana University, and began working with Busey.
In the study, Busey first “listened in” to the brains of both experts and
nonexperts as they looked at images.
That process involved a cap that looks a bit like something out of a science
fiction novel — a tight-fitting cloth headpiece wired for sound with dozens of
small multi-colored receptors.
Participants sat in a large recliner in a tiny room deep in the heart of the
psychology building, looking at images on a computer screen as their brains sent
The headpiece allowed him to “hear” neurons firing in the brain, producing a
pattern that could be studied, Busey explained.
That data was contrasted against other data showing how people recognize human
That practice, called configural processing, involves relating parts of an image
to each other. For example, people seeing a human face generally process it
configurally — meaning they see it as a whole, rather than eyes, nose and mouth
once at a time.
That’s how fingerprint experts see the prints they’re examining, especially when
comparing one to another and especially if those prints are surrounded by
“noise” — dust, dirt or other smudges that might be found at a crime scene,
“Experts were better overall,” he said. “They seemed to have superior visual
memories to do particularly well with prints embedded in noise.”
Non-experts — or novices — were affected by longer delays between seeing the two
prints they were comparing and showed no evidence of configural processing.
The study’s findings were published in the February edition of the journal
Vanderkolk and Busey have also presented their findings throughout the world, at
scientific seminars and similar gatherings. Now, they’re hoping their
findings will have larger implications in courtrooms
across the nation.
They believe prosecutors and attorneys will use their findings to reinforce the
admissibility of fingerprints used as evidence in court proceedings.
Fingerprints are one of several forensic methods that are often questioned in
court through what’s called a Daubert hearing — so called after the 1993 civil
case Daubert v. Merrell Down Pharmaceuticals.
The hearing is, in effect, a mini-trial within a trial, conducted before the
judge over the validity and admissibility of expert opinion testimony.
“Our hope is to now take these findings and, at a Daubert hearing, say we think
experts … should be allowed to testify,” Busey said.
electrophysiological evidence for configural processing in fingerprint experts
Abstract from ScienceDirect.com
The Journal: Vision Research
Volume 45, Issue 4, Pages 397-525 (February 2005)
Visual expertise in fingerprint examiners was addressed in one behavioral and
one electrophysiological experiment. In an X-AB matching task with fingerprint
fragments, experts demonstrated better overall performance, immunity to longer
delays, and evidence of configural processing when fragments were presented in
noise. Novices were affected by longer delays and showed no evidence of
configural processing. In Experiment 2, upright and inverted faces and
fingerprints were shown to experts and novices. The N170 EEG component was
reliably delayed over the right parietal/temporal regions when faces were
inverted, replicating an effect that in the literature has been interpreted as a
signature of configural processing. The inverted fingerprints showed a similar
delay of the N170 over the right parietal/temporal region, but only in experts,
providing converging evidence for configural processing when experts view
fingerprints. Together the results of both experiments point to the role
configural processing in the development of visual expertise, possibly supported
by idiosyncratic relational information among fingerprint features.
Synopsis from Dr. Busey's web page:
How do forensic scientists make fingerprint identifications?
Fingerprints contain remarkable structure. The dynamics of the development of
prints in utero dictate that ridges maintain a similar separation. This
provides the kind of regularity that could enable perceptual learning processes
to develop and improve the extraction of features from prints.
To address this question, we designed an experiment that extracted out what we
thought were the essential elements of an identification. We tested both experts
and novices. We first created pairs of print fragments:
We then presented one fragment for subjects to view for about 1
second and then showed a mask for either 200 milliseconds or 5 seconds. Then we
tested the observer with two choices and asked them to pick the one they saw
original. Here is a diagram of the sequence of events:
Fingerprints are often corrupted by visual noise and sometimes
only part of a print is visible. To simulate these effects, we sometimes added
visual noise or partially masked the fragments at test. Here are examples of
What we found
The basic question we're asking is whether experts before better than
novices, and if so, under what conditions. The bottom line is that experts
performed better than novices is all conditions, and perform especially well
when full fragments are embedded in noise. We were able to tie this to a
particular brain process called configural processing, and we use a brain
recording technique called electroencephalography (EEG) to identify this
particular mechanism. We relied on a known component of the EEG signal called
the N170, and the fact that it is delayed when a face (known to be processed
configurally) is inverted. The inversion disrupts the configural process,
causing the delay in the N170.
It turns out that fingerprints have an orientation, and that fingerprint experts
almost always view fingerprints in an upright orientation. In fact, they will
sometimes invert a particularly difficult print in order to gain perspective on
To test to see whether configural processing was active when fingerprint experts
viewed upright fingerprints, we showed upright and inverted fingerprints to
novices and experts. We also showed upright and inverted faces. We expected both
groups to show the delayed N170 component when faces were inverted, but this
effect should only occur in fingerprint experts for the fingerprints.
Here is the data:
The dashed lines come from faces, and the solid lines from
fingerprints. The x-axis is time, with 0 the time that the stimulus (face or
fingerprint) comes on. The y-axis is amplitude recorded from the back-right part
of the head, which records mainly amplitude from the occipital/parietal region
of the brain.
As predicted, the experts had a difference for both faces and fingerprints, but
the novices had a difference only for fingerprints in the N170 component.
This result allows us to attribute the configural processing we observed in the
behavioral experiment to changes in perceptual processing that occur very early
on in the visual stream.
To summarize, the results of the two experiments provide
converging evidence that the visual expertise gained by fingerprint examiners
has profound effects on the earliest stages of visual processing, which has lots
of potential to help them recover fingerprint detail from noisy or degraded
For More Information
To participate in future on-line (web-based) experiments,
contact Tom Busey at firstname.lastname@example.org. Please specify if you have fingerprint
The entire article may be accessed from Dr. Busey's
message board is always open: (http://www.clpex.com/phpBB/viewforum.php?f=2).
For more formal latent print discussions, visit
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