The department's policy on fingerprinting has not changed, said Charlie Makinnie, the mayor's liaison to the police. ''They have always had a policy where you have to have probable cause or reasonable suspicion,'' he said.
The IBIS unit is also being tested in Eagan, Minn., a Minneapolis suburb. There, too, the device raised public concerns, according to Kent Therkelsen, the Eagan police chief. He said the device was used only when the police already had legal authority to take prints. ''It doesn't change our laws, it doesn't change our ethics,'' Chief Therkelsen said. ''It is just a tool for a very specific niche.''
Eagan police used the device recently when a shoplifter provided dubious identification. While the suspect was still in the store, officers determined her identity and learned that there were active warrants for her arrest.
In addition to Portland and Eagan, the IBIS device is being used in Ontario, Calif. The Ontario Police Department deployed the devices in October 2001 and now has 50 in service, enough for use by about 85 percent of the on-duty patrol force, said Ann Punter, the department's forensics manager. According to a case study published by Identix, the devices were used more than 3,000 times in Ontario from June to October 2003, yielding more than 700 matches and leading to about 170 arrests. The device has also proved useful in death investigations, Ms. Punter said, having helped identify victims of a hit-and-run accident and a suicide.
Besides Identix, a handful of other companies offer fingerprint identification devices that are tailored for law enforcement. A law enforcement agency in Texas is expected to begin testing a new product from Motorola called Mobile AFIS at the end of September. Mobile AFIS is expected to be available for shipment in December, and government agencies in Serbia have ordered about 1,000 for use in law enforcement and other settings, said David G. Hall, Motorola's product manager for the system.
Motorola, through its Printrak products, is one of several providers of the large computerized systems that store the fingerprint records. These systems are called automated fingerprint identification systems or AFIS's.
The mobile automated system can match fingerprints against those records using radio communications or over a cellular network. It can also store up to 5,000 fingerprints on its hard disk, enabling the user to check a print without the need for wireless communications.
The system can run on modified iPaq's and other devices that run the Windows Pocket PC or Windows CE .NET platforms.
There is potential for sales in the private sector as well, Mr. Hall said. For example to verify identity during a banking transaction, a customer's fingerprint could be matched against one that is encrypted and stored digitally on a wallet-size ID card that could be swiped through the device.
Atsonic, based in Schaumburg, Ill., is another company that offers a fingerprint identification system. Called SweetFinger, the device is in the testing stage at several law enforcement agencies, said Joe Pirzadeh, the company's chief executive. It can communicate directly with law enforcement systems to match prints, Mr. Pirzadeh said, and it can cost $1,500 to $4,000 depending upon options.
The company also offers SweetFinger to identify and track students boarding and exiting school buses, and a Global Positioning System tracking option to monitor the location of the buses. The system has been deployed by the Ontario-Montclair school district in California.
Barriers against wide-scale implementation of biometrics tools in law enforcement remain, including cost. The technology is still new and expensive. But for many law enforcement officials, the hope is that the use of these tools becomes routine.