SYRACUSE, N.Y. -- There are 1,228 cameras mounted on the trunks of police cars across New York.

From the tiny village of Jordan to New York City, the cameras snap a picture of every plate on every car that drives by.

It's an effortless 100 pictures a minute for each camera, called an automatic license plate reader. A few pictures each shift might produce an alarm from a statewide hotlist updated daily: The registration is suspended, the car is stolen, the driver is wanted.

But the rest of the plate pictures - millions a day across the nation - are mostly warehoused in databases where they sit for anywhere from months to years.

Most of the pictures are seen by no one. If they were, they would show where millions of innocent drivers have been.

The license plate readers are a massive fishing net that is effortlessly cast. This is what makes them so popular and feared. They are the paradox that is intelligence technology.

The data socked away has been used to solve crimes and stop violence. But it also documents to the government where law-abiding people have been for months and even years.

This graphic shows how a license plate reader works.

Does that matter?

It did in New Hampshire. Lawmakers there voted in January to ban the license plate readers aside from limited use in toll plazas.

The laws have not kept pace with the technology. In New York, there are no laws regulating how the records can be used or how long the records should be kept.

Departments are left to make up their own rules. They run the gamut -- from keeping no records at all to ferreting them away for five years or more.

As the data piles up in communities across the nation, the American Civil Liberties Union is in the odd spot of agreeing with Rand Paul and his libertarian supporters. Both fear the damaging potential of so much personal information in the hands of strangers.

The debate over how the technology is used and who has access to the data it creates is just beginning.

Last month, the U.S. Department of Homeland Security pulled the plug on a plan by Immigration and Customs Enforcement to have a private company build a nationwide database of license plate scans after the concept became public.

At the same time, Onondaga County continues adding to a database that contains pictures of license plates captured by 19 different police agencies across Central New York. On slow days, road patrol officers cruise high-traffic spots with the goal of scanning as many plates as possible.

Onondaga County's database has 5.2 million records. All of the participating police agencies and the state police are allowed to search the database.

Sgt. Crayg Dykes, of the Onondaga County Sheriff's Office, oversees several road patrol deputies who use the county's 13 license plate readers. One day, out of curiosity, he entered his own license plate number.

A trail of where he'd been over the past year popped up on his screen. Though Dykes knew the county had more than a dozen license plate readers deployed, he was surprised to see his own path over time. It made even him uneasy.

"I can see how it would be creepy if I wasn't in this business," Dykes said.

Onondaga County keeps the license plate pictures in the database for one year.

Deputy Robert Bechtel, who patrols the roads in northern Onondaga County, spends each shift with the license plate reader as his sidekick.

As he drives and responds to calls, the cameras continuously scan the cars that drive by. Each click gets fed back to the county's database. The number and location are both recorded.

On slow days, the reader does extra work. Bechtel cruises the Shop City parking lot off of Teall Avenue for cars on the hotlist. It's usually a treasure trove of potential hits.

When the alarm sounds, he double checks the plate number, then waits for the owner to show up.

Bechtel's car is outfitted with the Mobile Plate Hunter 900. It's a model made by ELSAG, the main U.S. manufacturer of license plate readers.

Two cameras are mounted, like eyes, on the trunk of the car. They are linked to the computer in the patrol car, which has access to both the state's hotlist of wanted plates, which is updated daily, and the county's database.

Over the past decade, ELSAG has sold nearly 8,000 license plate readers to 2,000 police agencies and municipal parking authorities. The majority of the purchases were paid for by government grants, said Nate Maloney, of ELSAG.

There has been a similar explosion in private use, mostly by the car repossession industry, through other manufacturers. ELSAG does not sell to private users, Maloney said.

The technology that powers the plate hunter and other license plate readers was invented in Great Britain in the 1970s as part of that nation's ongoing efforts to stop terrorism at the hands of the Irish Republican Army.

As technology improved and became more affordable, the cameras went from little-used spy gadgets to must-haves for police departments big and small.

New York State Police have the largest single network of license plate readers in the state. The agency has 140 in cars. The state police also have their own database where they keep plate pictures for five years.

While state police are allowed access to Onondaga County's database, the state does not allow other agencies to search its records, a spokeswoman said.

The rules about who sees the data and how long it gets kept should be made clear when a police department buys the license plate readers, said David Roberts.

Roberts is a police technology expert with the International Association of Chiefs of Police, based in Alexandria, Va.

"We do think that agencies absolutely have to have policies in place that define a data retention period," Roberts said. "Where agencies are going to get into trouble is if they implement the technology and don't have policies in place."

Roberts also said there is little specific data that measures the license plate readers' success. Few, if any, departments keep statistics on how many arrests or other law enforcement actions were the direct result of a license plate reader.

Most just have powerful anecdotes. Like this one:

Bechtel, the Onondaga County Sheriff's deputy, was working his usual shift when he heard a call for a kidnapping in progress. A man had his ex-girlfriend at knifepoint.

Police had his plate number. Bechtel's license plate scanner was hunting every car that passed for matching letters and numbers.

Finally, there was an alarm. Bechtel looked at the plate number to make sure it was the same. Then he pulled the car over and went to the drivers' window with his gun drawn.

He freed the woman and arrested the man.

There's no doubt that Bechtel is the hero. He walked up to the car and pulled the gun. He made the arrest and saved the girl.

But he can't tell the story without first giving credit to his silent and always-watchful partner: the Plate Hunter.

Contact Marnie Eisenstadt at meisenstadt@syracuse.com or 315-470-2246.