Biometric” technology, which is a topic adored by sci-fi writers and fans alike, has found a real-world implementation with law enforcement.  Dozens of police departments nationwide are gearing up to use a tech company’s already controversial iris- and facial-scanning device that slides over an iPhone and helps identify a person or track criminal suspects.

But its use has set off alarms with some people who are more concerned about possible civil liberties and privacy issues.  Constitutional rights advocates are concerned, in part because the device can accurately scan an individual’s face from up to four feet away, potentially without a person’s being aware of it.

“This is (the technology) stepping out of the cruiser and riding on the officer’s belt, along with his flashlight, his handcuffs, his sidearm or the other myriad tools,” said John Birtwell, spokesman for the Plymouth County Sheriff’s Department in southeastern Massachusetts, one of the first departments to use the devices.

“What we don’t want is for them to become a general surveillance tool, where the police start using them routinely on the general public, collecting biometric information on innocent people,” said Jay Stanley, senior policy analyst with the national ACLU in Washington, D.C.

The smartphone-based scanner, named Mobile Offender Recognition and Information System, or MORIS, is made by BI2 Technologies in Plymouth, Massachusetts, and can be deployed by officers out on the beat or back at the station.  An iris scan, which detects unique patterns in a person’s eyes, can reduce to seconds the time it takes to identify a suspect in custody. This technique also is significantly more accurate than results from other fingerprinting technology long in use by police, BI2 says.

iPhone 4.0 empowers you a more realistic effect because it has front-facing camera. Just as we see in science-fiction blockbusters, iris recognition is a new and cool method for identification based on the biological features, which has significant value in the information and security field.   When attached to an iPhone, MORIS can photograph a person’s face and run the image through software that hunts for a match in a BI2-managed database of U.S. criminal records.

In other use cases of recognition technology, Facebook’s Automated Photo Tagging’s new feature “recognizes” faces in photos, shortening the often tedious tagging process, which enables users to connect a face in a photo with an actual friend on Facebook. The process is now semi-automated: Facebook provides suggestions for individuals in photos, and the user chooses to accept or reject them.

Facial recognition and iris scans have some practical uses in more ways than one, but they also raises some privacy concerns. Nevertheless, such technology can be used to combat identity fraud, and could potentially be used in traffic stops when a driver is without a license, or when people are stopped for questioning at U.S. borders.