In August 2011 the ACLU issued public records requests to over 380 state and local law enforcement agencies and found that virtually all of the departments that responded tracked cellphones, most without warrants.
The majority of the 200 agencies that responded engaged in some cellphone tracking. Only a handful of those said they regularly seek warrants and demonstrate probable cause before tracking cellphones, according to the ACLU report.
Most law enforcement agencies said they track phones to investigate crimes, while others said they use tracking only in emergencies like a missing persons case. Only 10 agencies said they never use cellphone tracking.
Some law enforcement agencies provided enough documentation to paint a detailed picture of cellphone tracking activities. For example, Raleigh, North Carolina, tracks hundreds of cellphones per year based on invoices from phone companies. In Wilson County, North Carolina, police obtain historical tracking data where it’s “relevant and material” to an ongoing investigation, a standard the ACLU notes is lower than probable cause.
Police in Lincoln, Nebraska, obtain GPS location data on phones without demonstrating probable cause. GPS location data is even more precise than cell tower location information, according to the ACLU.
Furthermore, the ACLU notes that cellphone tracking has become so common that cellphone companies have manuals that explain to police what data the companies store, how much they charge for access to data and what’s required for police to access it.
However, some law enforcement agencies do seek warrants and probable cause before tracking cellphones. Police in the County of Hawaii, Hawaii, Wichita, Kansas and Lexington, Kentucky, do seek a warrant and probable cause.
The ACLU says that if “police departments can protect both public safety and privacy by meeting the warrant and probable cause requirements, then surely other agencies can as well.”
The civil liberties organization argues that cellphone companies have made transparency worse by concealing how long they store location data. For example, Sprint keeps tracking records for as many as 24 months and AT&T maintains records from July 2008, according to the U.S. Department of Justice.
In an open letter to wireless carriers, the ACLU implores them to “stop routinely retaining data about your customers’ location history that you happen to collect as a byproduct of how mobile technology works,” and asks them to disclose how information is being kept and give customers more control over how their information is used.
The ACLU is not alone in its concern. Members of both chambers of Congress have introduced legislation that would require law enforcement agencies to obtain a warrant before tracking cellphone data. The act, known as the Geolocation Privacy and Surveillance (GPS) Act, has bipartisan support but has not yet moved out of committee.
“Law enforcement, in my mind, has overstepped its bounds and thrown out many of our Fourth Amendment rights,” said Utah Republican Rep. Jason Chaffetz.
Another effort is being made by Vermont Democratic Sen. Patrick Leahy, to update the 1986 Electronic Communications Privacy Act (ECPA), which includes “a warrant requirement for real-time tracking, but not for historical location information.”
“I think the American public deserves and expects a degree of personal privacy,” said Chaffetz. “We in America don’t work on a presumption of guilt.”
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