CARLSBAD, Calif. – This city is expanding its use of automated license plate readers into a system that aims to collect the registration information of every vehicle that enters the city.

The $1 million Police Department project — which will add stationary cameras at 14 intersections, creating a virtual gateway at the city's borders — was approved by the City Council last week, sparking outrage over privacy rights and government control from several residents and one council member.

Four council members said they were confident the information can be kept secure and that the system will increase safety for residents and police officers. They also said it could deter criminals.

"To me, $1 million is a drop in the bucket when you are trying to protect 100,000 or more people, and everyone who comes into our city every day," said Councilman Keith Blackburn, a retired police officer. "I don't think this … is going to violate privacy."

Several law enforcement agencies in San Diego County use license plate readers on a more limited basis. The devices are attached to certain patrol cars, scanning the plates of vehicles that cross their paths. They have proved especially useful in finding stolen cars, officials have said.

Other cities across the nation, from Laguna Beach in neighboring Orange County to Palm Beach Shores, Fla., have focused plate readers on key access points into town — the blanket effect that Carlsbad is going for with its expansion.

But privacy rights advocates say widespread use of the devices can be a slippery slope and that laws are needed to govern how and when the information can be used.

"You can end up with a record of innocent drivers stored for an endless amount of time," said Kellen Russoniello, a staff attorney at the American Civil Liberties Union of San Diego. "It's fairly easy for nefarious government actors to find out where [people] go to the doctors, where they practice their religion. … You can basically track wherever a person goes."

Carlsbad first equipped four patrol cars with the readers in 2011 and two remain in use, police Capt. Mickey Williams told the City Council.

The cameras automatically recognize license plates and check the information against a law enforcement database, searching for hits about stolen vehicles, missing persons and other police cases.

In Carlsbad, Williams said, the data collected will be deleted after about a year unless it's needed for a criminal investigation.

Councilwoman Cori Schumacher cast the only vote against the plan. "This would greatly affect the private lives of our citizens," she said.

The equipment is expected to cost over $1 million in the first year of operation.