The reader takes in license information from all nearby vehicles, not just a suspect's. And that information can be fed to other law-enforcement agencies, according to the American Civil Liberties Union (ACLU), which published a report on the issue in July.
About 30 Bay Area government agencies use license-plate readers, according to a report by the Center for Investigative Reporting, including the City of East Palo Alto. Menlo Park plans to add readers to its criminal-catching arsenal.
The Santa Clara County Sheriff's Office gave a reader to each law-enforcement agency in the county and will gather the data countywide from multiple police departments. Palo Alto received its device at no cost, Perron said.
But the Sheriff's Office has not yet decided whether it only will use the information to solve crimes or will submit the information to a federal agency for broader intelligence purposes, Sheriff's Office Sgt. Kurt Stenderup said.
License-plate data is collected in the Bay Area through the Northern California Regional Intelligence Center, one of 78 "fusion" sites nationwide established after the Sept. 11, 2001, terrorist attacks.
"The goal is to create a system we can use to share information," Stenderup said. "We all know crime doesn't stay in one city."
Since the system is new throughout the county, Palo Alto police are working with other county law-enforcement agencies to write a policy that is consistent with state and federal law, Perron said.
The policy will include information on proper auditing and inspections of the system to ensure it is being legally used and the length of time records will be retained, he said.
"The initial plan at this point is for the Sheriff's Office to retain the data for a period of one year. The Santa Clara County Police Chiefs' Association will be discussing the system and policy governing its use at their next meeting on Aug. 8. And while the system went 'live' yesterday in Palo Alto, no data is actually being stored until Aug. 26," Perron stated in an email Wednesday.
Stenderup stressed that the system and policies governing privacy are "very much in the infancy phase."
Palo Alto police are governed by the department's procedures controlling access to law-enforcement information, Perron said. Officers are required to have a legitimate "right to know" and "need to know" in order to see the information.
The reader consists of four cameras mounted to the top of the car that can look forward and back, he said. The camera reads the information, which is fed into a database that is shared with county law enforcement. It can immediately flag any license plate that comes up stolen or for which police have a warrant, Perron said.
He maintained the device isn't doing anything that officers don't already do, but it will do it much faster.
"It is not different from officers typing in the license plate to an in-car computer, which we have been doing for 15 years. This automates it. It's an additional set of eyes," he said.
Millions of license plates are being read statewide each day, according to the ACLU. The reader photographs every license plate it encounters and adds a time and location stamp.
The ACLU found a wide disparity in how municipalities store data. Milpitas had no record-retention policy as of 2012, for example, but Los Angeles police keep the records for up to two years.
Former state Senator Joe Simitian, now a Santa Clara County supervisor, introduced a bill in 2012 that would have required California police departments and data-collection companies to purge the data after 60 days. The bill failed.
Civil-liberties watchdogs are squeamish about the expanded use of license-plate readers.
Because the technology is becoming ubiquitous, it can track a person's movements. The readers can identify what, where, when and with whom someone is congregating. An individual can be photographed going to church, school, a lover's home, a public or private meeting, a political protest or a medical appointment, the ACLU noted.
One computer-security consultant who asked the City of San Leandro for a record of each time the scanners had photographed his car received 112 images, according to a report by the Center for Investigative Reporting. One image from 2009 shows him and his daughters stepping out of his car in their driveway.
The Palo Alto City Council discussed license-plate readers, and privacy concerns, in January 2009 when it approved $40,000 to install a reader in a patrol car and one on a parking-enforcement vehicle. The technology was never installed, but the council at the time debated the implications to civil liberties.
Then-Vice Mayor Jack Morton questioned why the license-plate data would be held for longer than necessary to determine daily parking violations.
Councilman Larry Klein saw no civil-liberty concerns. Payment for license plates includes a contract with the state. The liberty of driving is granted with the agreement that some identifying data from licensing is available to law enforcement, he said.
TALK ABOUT IT
Do you favor the use of license-plate readers by law enforcement, and if so, what restrictions would you place on use of the data? Share your opinion on Town Square, the community discussion forum on Palo Alto Online.
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