Police agencies across the U.S. are building large databases of palm prints.
By Shaila K. Dewan, The New York Times
For more than a century, the fingerprint has been the quintessential
piece of crime scene evidence. But fingerprints are only a tiny part
of the story. All of a person's "friction ridged skin" is
distinctively patterned: soles, palms and even the writer's palm, as
the outer side of the hand is called.
Surveys of law enforcement agencies indicate that at least 30 percent
of the prints lifted from crime scenes - from knife hilts, gun grips,
steering wheels and window panes - are of palms, not fingers.
That is why in April, the New York Police Department began having
prisoners place their whole hand, not just their fingertips, on the
glass platen of a scanner when their prints are captured. Beginning
next month, the department will be able to do computerized matches of
the 100,000 palm prints it has already collected. As the database
grows, it will become one of the largest of its kind.
The cost of image storage and computerized matching equipment once
limited database entries to fingertips. But technological advances
have enabled a growing group of law enforcement agencies across the
country - about 30 so far, based on information provided by companies
that sell the systems - to build their own palm databases. The Los
Angeles metropolitan area began using one last month. Miami, Palm
Beach, Philadelphia and Indianapolis have created databases this
year. And Harris County, Tex., which includes Houston, has a database
in the works.
Using palm prints for identification concerns some defense lawyers,
who point out that the reliability of fingerprint matching has come
into question in the courts in recent years, and that there is even
less data available on palm prints. But proponents of using palm
prints note that none of the dozens of fingerprint challenges have
There is as yet no national repository for palm prints, but the
Federal Bureau of Investigation is currently assessing three systems,
including one by Sagem Morpho, the biometrics company based in
Tacoma, Wash., that designed New York's database and scanners.
Police departments have long taken palm prints with ink, either
routinely or case by case. But computerized databases are expected to
exponentially increase the number of matches, as they did with
fingerprints. Since 1999, when the F.B.I. computerized its
fingerprint database, its crime lab has matched about 1,200 crime
scene prints, more than five times the number found in 15 years of
laborious manual matching, said Stephen Meagher, the head of the
lab's latent print operation.
Though statistics on palm data are hard to come by, the law
enforcement agencies that have begun using palm databases have
reported good results, said Steven Nash, the chairman of the
International Association for Identification, adding that many
detectives have run prints from older cases. "They are getting hits
on previously unknown and unused latent palm prints that are just
lying around doing nothing," he said.
One city that has kept a count is Indianapolis, which has come up
with a match in 15 percent of its palm searches, according to
statistics provided by Identix, the company that created the system.
That is not as high as the 31-percent success rate for the city's
fingerprint database. But there are only 16,000 palms in the system
thus far, compared with 300,000 fingerprint records.
Investigators are hopeful that the palm technology will help solve
more property crimes, many of which depend on fingerprints for
resolution. Property crimes nationally are solved at a much lower
rate than violent crimes - 16.5 percent compared with 46.8 percent,
according to F.B.I. statistics.
"It's worth every cent, and especially the victims are going to think
that," said Sgt. Donna Wright, an investigator for the Palm Beach
County Sheriff's Office who has gotten two hits so far from running
palm prints on burglaries. "A burglar goes out and probably commits
300 or 400 crimes a year."
Police Commissioner Raymond W. Kelly of New York said through a
spokesman, "This is cutting edge technology that gives our detectives
another powerful tool to help solve crimes."
At the police academy in Manhattan last week, Officer Maximilian
Velazquez stood by a row of new ILS2 palm scanners, each one about
the size of a video arcade machine. The department has 83 of what
will eventually be 140 scanners - at least one for every precinct,
courthouse, transit and housing bureau. When officers book an arrest,
the machine prompts them through the print collection process.
Fingers, thumbs and palms are positioned on the glass in sequence, as
the print images appear, much magnified, on the screen.
The best thing about the new machines, said Officer Velazquez, a
coordinator in the computer training unit, is that it rejects faulty
prints, gently scolding with messages like "finger rolled too slowly"
or "finger shifted vertically."
Just as with the old scanners, each set of prints is transmitted
directly to the department's database, where the computer brings up
possible matches and a fingerprint examiner at Police Headquarters
makes the final determination as to whether it is a hit. With the new
database, examiners could conceivably make a match from a fraction of
a palm print smaller than a dime.
While a few departments have had palm print databases for several
years, New York will be one of the first to have a system that uses
live, or inkless, scanners that feed directly into the database, said
James E. Simon, the head of the N.Y.P.D.'s Central Records Division.
(The department has used live scanners for fingers since 1997.)
While the scanners offer images of astonishing resolution,
significant chunks of the fingerprint record-keeping system seem
stuck in the dark ages. For instance, the city scans in fingerprints
and transmits them to the state, which then makes hard copies and
mails them to the F.B.I., which rescans them into the national
When three people were murdered in an apartment over the Carnegie
Deli in Manhattan in 2001, the police ran a check on one suspect and
learned that he had been arrested in Georgia. The palm print card
from that arrest was carried to New York by a special courier, said
Barbara Thompson, a spokeswoman for the Manhattan district attorney,
Robert M. Morgenthau. The card matched a palm print found on duct
tape used to bind the victims.
The palm database is part of an upgrade to the New York Police
Department's print archive, including the digitization of two million
ink fingerprint cards dating back to 1981, which were not searchable
by suspect or arrest number. The database project will cost $5.9
million over the next five years, Mr. Simon said. The 140 new
scanners will cost an additional $5.8 million.
Why undertake a project like this when DNA profiling is advancing so
quickly? "DNA is subject to destruction," Mr. Simon said, adding that
340 World Trade Center victims were first identified by fingerprints,
and 50 of them remain identified only by fingerprints.
Some defense lawyers raise the same objections to palm print
identifications as they have to fingerprints. "The criminal courtroom
is no place to experiment with a scientific method that may
incriminate someone," said Steven D. Benjamin, the co-chairman of the
forensic evidence committee of the National Association of Criminal
But even if the scientific basis of palm matching is questioned,
Edward J. Imwinkelried, an evidence expert and professor at the
School of Law at the University of California at Davis, said that
judges will most likely still admit it as "nonscientific expertise,"
just as they have sometimes done with fingerprints.
Mr. Meagher, of the F.B.I. crime lab, said that the scientific
underpinnings of palm print identification are the same as those of
fingerprint identification, and he does not expect either to be
successfully challenged. "It wouldn't surprise me if four or five
years from now we were having the same conversation about adding
footprints" to the database, he said.