ALAMEDA -- The public can weigh in on the city's proposed policy for allowing police to use license plate readers on their patrol cars during a Monday forum at the Alameda Free Library.

The event, which will take place at 6:30 p.m., follows the City Council deciding in October that police can seek grant money to purchase the readers, but still wanting more public input before officers can begin working with the devices on the street.

While the Automated License Plate Recognition devices can only be used for official and legitimate law enforcement business, including on routine patrols, the draft policy that city officials are considering also says that reasonable suspicion or probable cause will not be required to use them.

The policy also says the police department will make it a priority to use the devices in a neighborhood where a homicide, shooting or other major incident has occurred. The safeguards to protect privacy include having regular audits and having officers use a password-protected system so that those who have access to the information can be traced, and having all non-law enforcement requests for any of the collected information go through a supervisor.

The move to secure the license plate readers comes after police field-testing two of the devices on a single patrol car last year. Officers used them to take digital images of nearby license plates as a way to locate vehicles that may have been stolen or connected with a crime.

Within about two weeks after first using them on Sept. 18, the devices scanned about 97,000 plates and scored about 85 "hits" on suspicious vehicles, police Chief Paul Rolleri told the council. The plates scanned were within about 50 feet of the patrol car, and the hits included vehicles stolen in San Mateo and San Diego, Rolleri said.

What concerned the council, however, was whether collecting the data was an invasion of people's privacy since license plates of law-abiding citizens are scanned as the patrol car cruises past. The cameras can register up to 1,800 plates per minute at speeds of up to 160 mph, according to a background report prepared for the council. The collected data typically includes a black-and-white plate image, a contextual color image, GPS coordinates and the date and time the image was captured.

The system can cost between $10,000 and $25,000 depending on the manufacturer and the number of cameras mounted on a patrol car, which can be up to four. If the council approves the draft policy and police can get funding, the department will likely enter into an agreement to process the data with the Northern California Regional Intelligence Center, an agency that helps local, state and federal law enforcement collect and analyze information on possible criminal threats.

A representative from the center is expected to take part in next month's forum at the library. Others panelists will represent the police and the American Civil Liberties Union. The center keeps the collected data for 12 months before deleting it, a time frame that Rolleri said he supports because it gives police enough time to retrieve the information if it's needed for an investigation.

The devices field-tested in Alameda were from Lehr Auto/Pursuit North, a company that the police department uses to install emergency equipment on its vehicles.

Reach Peter Hegarty at 510-748-1654 or follow him on Twitter.com/Peter_Hegarty.

if you go
The Alameda police will host a forum on license plate readers at 6:30 p.m. Monday at the Alameda Free Library, 1550 Oak St.