How the Government Is Tracking Your Movements

You Are Being Tracked.

Law enforcement is taking advantage of outdated privacy laws to track Americans like never before. New technologies can record your every movement, revealing detailed information about how you choose to live your life. Without the right protections in place, the government can gain access to this information – and to your private life – with disturbing ease.

As long as it is turned on, your mobile phone registers its position with cell towers every few minutes, whether the phone is being used or not. Since mobile carriers are retaining location data on their customers, government officials can learn a tremendous amount of detailed personal information about you by accessing your location history from your cell phone company, ranging from which friends you're seeing to where you go to the doctor to how often you go to church. The Justice Department and most local police forces can get months' worth of this information, without you ever knowing – and often without a warrant from a judge.

Here's a peek into what law enforcement can learn about you by tracking your location:

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Freedom from unreasonable government snooping has always been a foundation of liberty in America.

For many years, long before cell phones, law enforcement has only had to meet an easy legal standard to get some details about the phone calls a person makes and receives. Now the government is also lumping in location data, thereby getting even more personal information without showing probable cause to a judge – essentially doing an end-run around the privacy protections of the Fourth Amendment.

It's still unclear just how often law enforcement accesses Americans' cell phones without warrants. We do know that the cases number well into the thousands, possibly the tens of thousands. Some of them are especially concerning – in 2010, for example, Michigan police officers sought information about every cell phone near the site of a planned labor protest.

Under open-government laws like the Freedom of Information Act, the ACLU sought records from the Justice Department and hundreds of state and local police departments to learn more about their cell phone location tracking policies and practices. A second coordinated records request sought to learn how law enforcement uses license plate readers to track the whereabouts of American drivers.

What we learned was disturbing. Read on to find out more about these technologies, and where Congress and the courts stand on the issue.

Cell Phone Location Tracking

Of all of the recent technological developments that have expanded the surveillance capabilities of law enforcement agencies at the expense of individual privacy, perhaps the most powerful is cell phone location tracking.

In August 2011, ACLU affiliates filed public records requests with hundreds of law enforcement agencies in over 30 states, asking for policies, statistics, and other information on the use of cell phone location tracking.

We received over 5,700 pages of documents from roughly 250 law enforcement agencies – the vast majority of which have engaged in at least some cell phone tracking, many of them quite frequently. Most of them do not obtain a warrant.

Learn more about what we found on cell phone location tracking »

License Plate Readers

The government can track innocent people's whereabouts even if they're not carrying a cell phone – with automatic license plate scanners. Their use is spreading rapidly around the country, but until recently, the public had little information about how they are used to track motorists' movements, including how long data is stored, and whether police departments pool this information in state, regional or national databases.

Here's how automatic license plate scanners work: 

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In July 2013, the ACLU released a major report on the expanding use of this powerful tracking tool. The study is based on documents from hundreds of police departments requested by ACLU affiliates in 38 states and Washington, D.C. We found that they're more and more widespread, with few privacy protections in place.

Learn more about what we found on automatic license plate scanners »

The Courts on Location Tracking

In 2012, the Supreme Court ruled in U.S. v. Jones that the government conducts a search under the Fourth Amendment when it attaches a GPS device to a car and uses it to track the driver's movements. The court did not decide, however, whether police need a warrant to conduct GPS tracking, or whether a lower standard applies. The ACLU filed a friend-of-the-court brief urging the Court to find that the wealth of personal details gleaned from the 24/7 GPS location surveillance rises to the level of private information that is covered by the Fourth Amendment.

Since Jones was decided, courts around the country have been grappling with how to apply the ruling to location tracking using GPS devices, cell phone location information, and other technologies. A panel of the Third Circuit Court of Appeals has ruled that police need a warrant to attach a GPS tracker to a car (the ACLU reargued the case to the full court in May). The supreme courts of states around the country, including New York, Washington, Oregon, South Dakota, Virginia, and Massachusetts, agree. The Eighth and Tenth Circuits are currently considering the issue, in cases out of Missouri and Kansas.

Appeals courts have also begun to address whether police need a warrant to track a person's location using their cell phone. In an important victory for privacy, the Eleventh Circuit ruled in June 2014 that law enforcement must obtain a warrant to get people’s phone location histories from their cell service companies, and that failure to do so constitutes a violation of the Fourth Amendment. The Third Circuit has ruled that magistrate judges have discretion to require a warrant for cell phone location data, while the Fifth Circuit has disagreed, holding that people have no reasonable expectation of privacy in their location information. The Fourth Circuit is considering a case involving warrantless requests for months' worth of historical cell site location information, and in a narrow opinion, the Sixth Circuit has ruled that a warrant is not required for three days' worth of real-time cell phone location tracking. State courts are also starting to address cell phone tracking, with the New Jersey and Massachusetts supreme courts holding that a warrant is required to track cell phone location data.

The ACLU has filed friend-of-the-court briefs in most of these cases, and will continue to advocate for courts to apply full Fourth Amendment protections to electronic location tracking by police.

Congress on Location Tracking

The GPS Act, presently pending in Congress, would go a long way in protecting our location privacy by requiring law enforcement to get a warrant based on probable cause before accessing private location data.

TAKE ACTION: Tell your representatives in Washington to support the GPS Act »


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