Law enforcement agencies have been using an obscure cellphone tracking tool

Local law enforcement agencies from suburban Southern California to rural North Carolina have been using an obscure cellphone tracking Mass Surveillance on a Budget, a new tech toolthat allows them to follow people’s movements months back in time. Local law enforcement is at the front lines of trafficking and missing person cases, yet these departments are often behind in technology adoption. All mobile devices are assigned what’s called an advertising identification number, a unique code that allows apps with location services to target consumers with promotions.

Virginia-based Fog Data Science offers a service called ‘Fog Reveal. Public records and internal emails obtained by The Associated Press show police have used the database known as Fog Reveal. Fog Reveal has been used since at least 2018 in criminal investigations ranging from the murder of a nurse in Arkansas to tracing the movements of a potential participant. Reveal uses an identification number to track a device’s wanderings when location services are enabled. Federal oversight of companies like Fog is an evolving legal landscape.

Mass Surveillance on a Budget:

Police have used "Fog Reveal" to search hundreds of billions of records from 250million mobile devices, and harnessed the data to create location analyses known among law enforcement as patterns of life. It’s sort of a mass surveillance program on a budget. That information is then sold to companies like Fog. It relies on advertising identification numbers, which Fog officials say are culled from popular cellphone apps. 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.

The company said it does not access or have anything to do with personally identifiable information and is leveraging commercially available data. The company was developed by two former high-ranking Department of Homeland Security officials. Fog’stech tool is accessed through a web portal. Investigators can enter a crime scene’s coordinates into the database, which brings back search results showing a device’s Fog ID, which is based on its unique ad ID number.

Fog heavily markets its product to law enforcement by promoting what it calls a ‘pattern of life’ analysis, which can stretch back months. Fog, which is listed as a task force sponsor, has been invaluable to cracking missing children cases and homicides. The secrecy surrounding Fog, however, there are scant details about its use, and most law enforcement agencies won’t discuss it, raising concerns among privacy advocates that it violates the Fourth Amendment to the US Constitution, which protects against unreasonable search and seizure.