TEMECULA -- The city has invested more money in a camera system for Temecula police cars that law enforcement authorities credit with boosting the number of stolen vehicles recovered by the Police Department.

The system, which links cameras positioned on a patrol car like a three-eyed sentry to a database, works by matching captured images of vehicle license plates with a registry of plates linked to wanted vehicles.

During a recent meeting, the City Council approved the department's request to buy three systems at a cost of $75,000.

After those are installed, the city will have five police cars with the camera systems on the streets.

During a typical shift, the system's cameras, which snap and record images automatically, can collect the images of about 3,000 plates.

Since the first cameras were installed in the summer of 2007, the department has had more than 1,600 hits with the system, said Lt. Jeff Kubel, the city's traffic lieutenant.

A hit is tallied when the image of a license plate matches an image in the system's customizable database.

After noting the hit, an officer double-checks the plate number with a dispatcher.

"It is important to understand that many times, a single license plate can result in numerous hits, primarily because the plate can be scanned repeatedly by more than one camera," Kubel said. "Of the (1,600-plus) hits … we have recovered about 30 stolen vehicles and arrested 20 people for auto theft."

In some communities, the systems have been used to find unlicensed drivers and people with unpaid traffic tickets.

Kubel, however, said the city isn't using the system to track or identify those types of violations right now.

Temecula's cameras are looking for stolen vehicles, stolen plates, missing persons and other wanted vehicles, he said.

At the end of the day, the data collected by the cameras is downloaded into a database at the station.

The system is not tied into any other stations or agencies, but Kubel said there is a potential for sharing information between agencies.

"We may progress to this in the future, but there is nothing in the works currently," he said.

Greg Lary, vice president of West Coast operations for the city's vendor, PIPS Technology, said Temecula has been among the most progressive in its use of the systems among about 400 agencies using them nationwide.

As with most technologies, the camera systems are evolving rapidly, and Lary said PIPS is working on lower-profile cameras that will take up less space.

Prices also are starting to drop a bit, making the systems more affordable for smaller police departments, he said.

Some privacy advocates have complained about the recent proliferation of the systems, calling them a Big Brother type of intrusion into a motorist's daily life.

Especially troubling for some of the advocates is the ability of the system to store vehicle license plate images tagged with global positioning system coordinates.

That information can be used to track a vehicle's movement over time -- if the license plate had been recorded multiple times -- and pinpoint a primary vehicle owner's approximate location.

Law enforcement officials, in turn, have responded to those concerns by noting that using the system in exactly that manner has led to the arrest of a murderer in Los Angeles and a hit-and-run driver in Escondido.

Lary, well-versed in the privacy issues that have been raised in public forums, said the system is not doing anything a police officer couldn't do manually.

He said the system merely makes easier a long-standing police activity -- entering a license plate number into a computer or calling a dispatcher to run the plate.

"With (multiple) cameras running simultaneously, they can scan a very large amount of space in a shorter amount of time," he said.

Without the system in place, an officer typically pulls to the side of the road to enter information into their onboard computers.

"Their eyes are down. They're stopped. They're typing in that system and checking in with their dispatchers," he said.

That's a time-consuming process, and it's time the officer could be spending looking for criminal activity, Lary said.

Talking specifically about the time-saving nature of the systems, former Temecula Police Chief Jerry Williams said recently that the camera-equipped cars can be used to document the vehicles at the scene of a crime -- a process that used to involve an officer handwriting dozens, if not hundreds, of plate numbers and running them through the system.

Another benefit, Williams said, is the ability to customize the systems.

For instance, he said, there was recently a rash of graffiti in the city that was likely the work of a gang member who was released from prison.

Williams said the systems could be programmed to look for that gang member's license plate, making it easier to find the suspected tagger.

Glenn Reynolds, a University of Tennessee professor who has written about the camera systems for Popular Mechanics, said they have virtually no use in fighting crime or preventing terrorism.

"It's social control," he said in a phone interview.

Talking about a study that looked at the use of the surveillance cameras in Britain, Reynolds said there was very little use of the systems to prosecute serious crimes.

Instead, law enforcement authorities there have been using them for "revenue enhancement": picking off the low-hanging fruit, such as traffic ticket scofflaws and other minor criminals.

"They're controlling people and extracting money from them," he said.

For those who argue that picking that low-hanging fruit helps keep a healthy number of officers on the streets and a community safe, Reynolds said the systems should be sold that way.

"Sell it as a tax on stupid people. Let them say so," he said.

As these systems become more popular in the United States, Reynolds said, he also is concerned about the idea of databases filing up with images of GPS-stamped license plates registered to law-abiding citizens.

Kubel, however, said the idea of storing millions of license plate images for use in future cases doesn't make much sense on a computing level.

To make room for the new data that is downloaded at the end of a typical shift, some of the old data is purged, he said.

Call staff writer Aaron Claverie at (951) 676-4315, ext. 2624.