LAPD: All cars are under investigation

The Los Angeles Police Department says it cannot release information about its automatic license plate reader program because all cars in the Los Angeles metropolitan area are under investigation. 

The LAPD made this legal argument in response to a records request from the American Civil Liberties Union and the Electronic Frontier Foundation (EFF), which sought to find out what the license plate readers had captured, as well as the department's policies for retaining and sharing the data.

Automatic license plate reader (ALPR) systems like the one employed by the LAPD take photos of any and all license plates, storing the plate number, time and location.

The LAPD's legal argument for denying the records request is novel in that it characterizes data collection not tied to a specific criminal case as investigatory, arguing that it may prove useful in future investigations.

The LAPD's filing reads: "All ALPR data is investigatory — regardless of whether a license plate scan results in an immediate 'hit' because, for instance, the vehicle may be stolen, the subject of an 'Amber Alert,' or operated by an individual with an outstanding arrest warrant." 

In a blog post, the EFF's Jennifer Lynch criticized the LAPD's argument, saying that it carries significant Fourth Amendment implications: