The LAPD, the L.A. County Sheriff's Department and other law enforcement agencies in Southern California routinely scan millions of license plates via patrol-car-based devices that can track your whereabouts.

What do they do with the info? It's not entirely clear, but the record shows that cops have used such stored data to help piece together cases. Good right? Well, the American Civil Liberties Union wants to know more about the plate scanners that have been almost ubiquitous in SoCal:

The ACLU and the Electronic Frontier Foundation today announced the groups have jointly filed suit against the LAPD and the sheriff's department for allegedly failing to provide requested data under the California Public Records Act.

The organizations say cops failed to produce all the requested documents, including papers on how the plate numbers are used, info how officers are trained to use the readers and their results, and a week's worth of automatic license plate reader data.

See also: License Plate Recognition Logs Our Lives Long Before We Sin.

As LA Weekly reported in a story cited today by the ACLU, the LAPD hangs on to your plate-enabled whereabouts for five years. In greater L.A. cops have done about 22 scans for every one of the 7,014,131 vehicles registered in the county.

“Law enforcement can create a clear picture of the movements of law-abiding citizens,” the ACLU's senior staff attorney, Peter Bibring, told us last year.

Today he says:

Credit: Kevin Dean / Flickr

Credit: Kevin Dean / Flickr

Police can and should treat location information from ALPRs like other sensitive information — they should retain it no longer than necessary to determine if it might be relevant to a crime, and should get a warrant to keep it any longer. They should limit who can access it, who they can share it with and create an oversight system to make sure the limits are followed.

The suit, filed in L.A. County Superior Court, seeks the documents as well as related fees.

The EFF likens the data collection to a version of Big Brother, where cops can know where you were last summer:

By matching your car to a particular time, date and location, and then building a database of that information over time, law enforcement can learn where you work and live, what doctor you go to, which religious services you attend, and who your friends are. The public needs access to the data the police actually collected to be able to make informed decisions about how ALPR systems can and can't be used.


[@dennisjromero / / @LAWeeklyNews]

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