itwbennett writes: Photographs of nearly half of all U.S. adults — 117 million people — are collected in police facial recognition databases across the country with little regulation over how the networks are searched and used, according to a new study from the Center on Privacy & Technology at Georgetown Law. About 20 states, including Texas, Florida, Illinois, Ohio, and Pennsylvania allow police to search drivers license photo databases. Police in a handful of other states and cities San Fransisco, Los Angeles, San Diego, and Chicago can search criminal mug shots, the report said. Police agencies don't need a search warrant to search facial recognition databases, the report said. 'We are not aware of any agency that requires warrants for searches or limits them to serious crimes,' the authors wrote. 'This has consequences.'