KQED: Cellphone-Tracking Tool Offers Police ‘Mass Surveillance on a Budget‘ by Garance Burke and Jason Dearen (AP):
Local law enforcement agencies from suburban Southern California to rural North Carolina have been using an obscure cellphone-tracking tool, at times without search warrants, that gives them the power to follow people’s movements months back in time, according to public records and internal emails obtained by The Associated Press.
Police have used Fog Reveal to search hundreds of billions of records from 250 million mobile devices, and harnessed the data to create location analyses known among law enforcement as “patterns of life,” according to thousands of pages of records about the company.
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What distinguishes Fog Reveal from other cellphone location technologies used by police is that it follows the devices through their advertising IDs, unique numbers assigned to each device. These numbers do not contain the name of the phone’s user, but can be traced to homes and workplaces to help police establish pattern-of-life analyses.
“The capability that it had for bringing up just anybody in an area whether they were in public or at home seemed to me to be a very clear violation of the Fourth Amendment,” said Davin Hall, a former crime data analysis supervisor for the Greensboro, North Carolina, Police Department. “I just feel angry and betrayed and lied to.”