You've arrested someone for disorderly conduct, but he has no identification on his person. How do you know if he has a medical condition impacting his behavior, if he's wanted elsewhere or if he has a history of assaulting police?
Facial recognition system providers say they have a way to answer all these questions quickly with the various applications for their products in the law enforcement arena.
One of the possible applications was reported in the February 17, 2007, edition of "The New York Times," where Adam Liptak wrote about an experiment in Massachusetts.
Three facial recognition specialists ran a photo from the America's Most Wanted Web site against the state's database of 9 million digital driver's license photos. The mugshot looked like one driver, but the license had a different name on it. By alerting police of the similarity, officers were able to track down and arrest the suspect in New York City, where he was receiving welfare benefits under the alias.
While this mix of civil and criminal databases is not legal without a warrant in many states, there are many potential uses of facial recognition to assist law enforcement with catching criminals.The universal image
Dr. Joseph Atick, executive vice president and chief strategic officer of the Identix Division of L1 Identity Solutions, is one of the pioneers in facial recognition.
"About 17 years ago, those of us in the biometrics field started thinking about the future," Atick recalls. "We saw significant promise if computers could learn to recognize faces. We knew they could match fingerprint patterns, an important tool in law enforcement, to narrow suspect searches. We set out to develop the technology to help the law enforcement community with identification (ID) management and use the face as a biometric of choice."
One advantage of using face recognition is that photos are on most forms of ID and the police have used mugshots in identifying suspects for a long time.
"Although the technology we first used is primitive compared to today's, we began with the basics on a small database," Atick says. "We learned that the human's capacity for recognizing faces is limited to about 2,000, but we wondered what the limit was for a computerized system. Over the years we discovered that computerized facial recognition systems are highly scalable. They can store in memory an almost unlimited number of faces and search them with phenomenal speed."
For example, the U.S. Department of State uses a system to screen visa applicants, searching applicant photos against a database of 75 million faces, several thousand times per hour.
Facial recognition systems, usually a camera teamed with software on a computer linked to a central database, perform automated comparison of face images based on unique features of the face.
"The features used by the algorithm vary between suppliers, but typically are ones that do not change significantly over time due to differences in facial hair, glasses or aging," Glen McNeil, criminal justice product manager for Sagem Morpho Inc., explains.
"The products can be used on photographs as well as live still images and video images," says McNeil. "Facial recognition products can be used to identify an individual through a one-to-one comparison, like an e-passport check, as well as search a database, like a watch list at a border crossing, or to check for a duplicate enrollment."
Jonathan Forrester, vice president of marketing for ALIVE Tech Inc., describes two kinds of facial recognition systems. "The first is two-dimensional," he says. "It takes a digital photo and measures points on a face, such as the base of the nose to the edge of the right eye. There are 50 to 60 points on a face."