The Seattle Police Department has drafted a new policy to guide the use of facial recognition software. The department, which came under criticism over earlier efforts to introduce new surveillance technologies, took steps to get outside advice during the development of the policy on facial recognition software. The software would allow police to check images of suspects against a database with 350,000 mug shots from King County.

Photos in the database would be of people who’ve been arrested, fingerprinted and booked in jail. The department would purchase the “booking photo comparison software” with pending funds from a Department of Homeland Security grant.

While the technology might give pause to some privacy advocates, the American Civil Liberties Union has backed the policy because it narrowly limits the department’s use of the computer system and sets clear rules for oversight. Under the policy, the department can only use the software to identify “a person whom an officer reasonably suspects may be involved in criminal activity.”

This means that cops cannot use the technology to identify witnesses, victims, or other crime scene bystanders. The department is also not allowed to connect the database to “live” surveillance feeds, including the city’s currently offline “mesh network.”

“It would be a great way to expedite some searching we’re already doing,” Assistant Chief Carmen Best told a City Council committee on Wednesday. “This only allows us to do it much more quickly …” […]