Crime solving done by hand
Texas county's automated print system works across databases to track, finger suspects
- By Michelle S. Haase
- Sep 08, 2007
The Sheriff's Department in Bexar County, Texas, recently completed the installation of a new automated fingerprint identification system to help streamline the jail booking process and identify criminals more quickly.
Within its first week of use, the system provided a new lead in an unsolved 1993 homicide.
Before implementing the automated system, the county used
a manual database, but the growing population in the county ' which includes San Antonio ' has resulted in a larger number of arrests, and the Sheriff's Department had a hard time keeping up.
'We're averaging an intake of 207 people a day with the same size staff
as 15 years ago, when we were handling maybe 100 people a day,' said David Dunbar, supervisor of Identification Services at the department. 'We needed to go automatic just to keep up with the processing involved.'
'When a person is brought in the door, we put them on the Fast ID system and see if they exist in our database.'
' DAVID DUNBAR, BEXAR COUNTY, TEXAS
The county uses NEC's Automated Fingerprint Identification System (AFIS), which captures fingerprints and palmprints and compares them to prints stored in the county's database.
If the county doesn't get a match, it can send the print to the Texas
Department of Public Safety, whose database contains about 6.5 million prints, said Chuck Thomas, client solutions manager at NEC's Identification Solutions Division.
If the Texas DPS does not find a match, the process goes to the next link in the chain, forwarding the print to the FBI. AFIS captures prints in the standard format specified by the National Institute of Standards and Technology, the only format the federal government accepts.
Thomas said that if no manual intervention is necessary ' that is, the print quality is good and the NIST requirements are met ' AFIS can conduct an end-to-end search from the county to the state to the FBI in less than an hour.
For Bexar County, one of the key AFIS applications is FastID, which captures an arrestee's fingerprints ' usually one print from each hand ' before the formal booking process begins.We have your number
'When a person is brought in the door, we put them on the FastID system and see if they exist in our database,' Dunbar said. 'If they do, we know who they are, and we have their ID number that is already in our system, and we can process them a lot more expediently. In the long run, it's going to save the taxpayers money.'
AFIS can capture palmprints and as many as 10 fingerprints, and it can capture and match both flat and rolled prints. Rolled prints are taken by rolling the fingertip from one side to the other.
The system can capture live prints at booking, but it can also search the database using latent prints collected from crime scenes. To do this, the print is lifted from the scene with tape, after which a digital photograph is taken and scanned.
Both fingerprints and palmprints are collected and stored during booking. Palm prints are important because they often are the only type of print left at a crime scene.
'Thirty-five to 40 percent of all prints left behind at a crime scene actually come from some portion of the palm or the side of the hand,' Thomas said. These prints are left when criminals lean against, grip or press on objects.
Dunbar said Bexar County is the only county in the state that captures full-hand palmprints, which extend from the wrist to the tips of the fingers. The county shares prints with the Texas DPS so the agency can start populating its palmprint database, which is not yet online.
County officials decline to discuss the 1993 case because it's still under investigation, but the collection of prints on the database could produce similar matches.
'For years, these were pretty much the unsolved pieces because there was nothing to match against,' Thomas said. 'Once [Bexar County] populates its database, we anticipate a lot of crime scene hits that in the past they couldn't hit against.'