Super Bowl fans never knew it, but police video cameras focused on their faces, one by one, as they streamed through the turnstiles in Tampa on Sunday. Cables instantly carried the images to computers, which spent less than a second comparing them with thousands of digital portraits of known criminals and suspected terrorists.

In a control booth deep inside the stadium, police watched and waited for a match.

The extraordinary test of technology during the highest-profile U.S. sporting event of the year yielded one hit, a ticket scalper who vanished into the crowd, reported an official at the company that installed the cameras.

But the decision to scan the unwitting crowd at the Super Bowl and countless visitors to the popular entertainment district of Ybor City for days before the big game inspired support and opposition yesterday over the nature of the technology and its intended uses.

Police spoke of a benign new law enforcement tactic no more intrusive than the use of a video camera at a convenience store. Civil libertarians challenged the involuntary videotaping of football fans and the growing use by police agencies of digital databases of physical traits.

"This was just the latest tool," said Tampa police spokesman Joe Durkin, who reported that the system made 19 matches during Super Bowl week. All had criminal histories but had committed no crimes of a "significant nature." He said police made no arrests as a result of the surveillance cameras' use.

"It's identifying these people who have a propensity to whatever led them into being in the database, whether it's a known pickpocket or a flimflam person," Durkin said. "Had the system been able to identify a known terrorist and had Tampa police been able to stop him, this tool would have been invaluable."

The American Civil Liberties Union opposes the involuntary capture of biometric details, such as face-recognition data, DNA and retina scans. The organization, in its list of "Privacy Principles," considers the fingerprinting of convicted criminals a worthy exception.

"We are quickly moving to the point where law enforcement and the private sector will be able to identify us no matter where we go, no matter how anonymous we think we are," said Barry Steinhardt, the ACLU's associate director. "Not only is it going to rob us of our anonymity, but it's going to be used as a tool of law enforcement to round up 'the usual suspects' and to hassle people on the streets."

The practice is almost certainly legal, but it is in an emerging area of the law that has not been fully tested in court, said Harvard Law School professor Bill Stuntz.

It may seem troubling to some that police can conduct such surveillance, but the practice is similar to the use of police cameras at busy intersections to capture speeding motorists, Stuntz said. In those cases, license plate numbers snapped by the cameras are traced to the cars' owners, who are then mailed speeding tickets.

Casinos use face-recognition technology to identify card counters and other patrons considered undesirable, according to two providers of such systems. British police installed the American technology in the gritty East London borough of Newham in 1998 and have since reported a significant drop in crime.

In Newham, 300 cameras surveil the town center and such well-traveled locations as public transport exits. A town security official last year described the system, installed by New Jersey-based Visionics Corp., as less like Big Brother than "a friendly uncle and aunt watching over you."

Yet two years ago, thousands of Americans objected on privacy grounds when they learned that their driver's license photographs were being sold by states to a private company that wanted to create a national database for use by retailers to combat fraud. The states canceled the project.

The system used for the Super Bowl project, first reported yesterday by the St. Petersburg Times, was lent by companies seeking to market the technology to law enforcement agencies. Tampa police accepted the free use of the system as an experiment and worked with local and national police agencies to manage it during the week of the game, said Durkin.

Dave Watkins, managing director of Graphco Technologies Inc., said the event gave the company a chance to learn how the software would perform, which camera angles were most effective and how the lenses of the 20 video cameras should be focused in a public place.

As each person passed through the four main stadium gates, a camera captured dozens of images, which were fed into computers. The computers compared the portraits against a database assembled from law enforcement agency files by a Massachusetts company, Viisage Technology Inc., which markets the software. The digitized images were constructed using 128 facial characteristics -- everything from the width of a nose to the angle of a cheekbone.

Each apparent match at the game was designed to be flashed side by side onto a computer screen at a stadium command post. A police officer determined whether the faces were those of the same person. The turnstile images were then discarded.

"We had several possibles. We had one confirmed," said Watkins, whose company has no customers yet. "They did try to find the individual, but he had already left. He was a known ticket scalper."

Durkin, the police spokesman, said the crowd surveillance is both legal and appropriate.

"The courts have ruled that there is no expectation of privacy in a public setting," Durkin said. "I think the vast majority of the public, they welcome anything they can utilize to make their visit safer and do a preemptive strike on crime."

Nor does the technology suggest Big Brother, proponents say.

"For the last 10 years, every time you went to a bank, a McDonald's, a Dunkin' Donuts, a gas station, your image is being picked up," said Tom Colatosti, president of Viisage. "Not only is it being picked up but, worse, it's being stored."

[Written by Washington Post Staff Writer Peter Slevin and published Thursday, February 1, 2001.]

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