Government Location Tracking: Cell Phones, GPS Devices, and License Plate Readers
The government is taking advantage of outdated law on privacy and technology to track Americans like never before. 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 – and mobile carriers are retaining location data on their customers.
As a result, 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. Law enforcement can get months’ worth of this information, without you ever knowing – and often without a warrant from a judge.
Freedom from unreasonable government snooping has always been a foundation of liberty in America. But all too often, police take advantage of outdated privacy laws to get their hands on this valuable private information by demanding it without a warrant. For many years, long before cell phones, law enforcement has only had to meet an easy legal standard to get less-revealing data about phone calls. Now the government is inappropriately lumping in location data, and getting it without showing probable cause to a judge – essentially doing an end-run around the privacy protections of the Fourth Amendment.
The Justice Department and most local police forces are currently tracking Americans' cell phones without getting warrants – but just how common and widespread the practice is remains unclear. We do know that the cases number well into the thousands, possibly the tens of thousands. Some of them are especially disturbing, for instance, in 2010, 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.
State and federal courts around the country have made conflicting rulings on whether location information should be protected by the Fourth Amendment, and Congress is considering bills that would require investigators to get warrants. Opponents argue that such rules would hamper police investigations – but in fact, there are many police agencies that already get warrants for tracking with no problems reported. The ACLU is fighting in the courts and on Capitol Hill to make sure that you don’t have to choose between your cell phone and your privacy.
Proposed Location Tracking Reform Laws in Congress
There are two pending efforts in Congress on location tracking: one is a pair of bipartisan measures sponsored in the Senate by Senators Ron Wyden (D-Oregon) and Mark Kirk (R-Illinois) and in the House by Representatives Jason Chaffetz (R-Utah), Peter Welch (D-Vermont) and Jim Sensenbrenner (R-Wisconsin).
The other effort is part of democratic Vermont Senator Patrick Leahy’s proposal to update the 1986 Electronic Communications Privacy Act (ECPA), which the government also uses to secretly access people’s email accounts. The bill includes a warrant requirement for real-time tracking, but not for historical location information.
TAKE ACTION: Ask Congress to update ECPA today »
Supreme Court and Other Court Cases on Location Tracking
In January 2012, the Supreme Court ruled in U.S. v. Jones that the government violated the Fourth Amendment when it placed a GPS tracking device to Antoine Jones’s car and tracked his movements continuously for a month. Although this case was specifically about whether police need a warrant to put a GPS device on a person’s car, it is the closest the Court is likely to come anytime soon to addressing location tracking, and the decision could influence the law on cell phone tracking. 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 surveillance of GPS tracking rises to the level of private information that is covered by the Fourth Amendment.
Learn more about the importance of Supreme Court case U.S. v. Jones »
In 2011, two federal district court judges in New York and Texas turned down Justice Department requests for cell phone location information without a warrant. The ACLU filed a friend-of-the-court brief in the Texas case, which the government has appealed to the U.S. Court of Appeals for the 5th Circuit (the ACLU has again filed a friend-of-the-court brief). Since 2005, magistrate judges (who are below district court judges) in various places, including New York, Pennsylvania, Texas, and Washington, D.C., have ruled that the government needs a warrant for cell phone location history. Importantly, these two recent rulings in Texas and New York are the only times that district court judges have upheld magistrate judges on this issue (in 2010, the U.S. Court of Appeals for the Third Circuit ruled that magistrate judges do have the discretion to require a warrant for cell phone location data). In August 2012, the Sixth Circuit ruled that a warrant is not required for 3 days’ worth of cell phone location data.
Learn more about the federal district court decisions »
State supreme courts have made various rulings on the issue. The supreme courts of Washington, Oregon, and New York have said that a warrant is required.
Demanding Information About Government Location Tracking
Part of the problem with warrantless cell phone tracking is that the public is largely in the dark about the use and potential abuses of the government’s tracking methods. In 2007, the ACLU filed a FOIA lawsuit against the Justice Department to force the release of records on the use of people's cell phones as tracking devices. In September 2011, the U.S. Court of Appeals for the D.C. Circuit ordered the government to turn over a list of cases where phones were tracked without a warrant.
Learn more about the ACLU’s FOIA lawsuit against the Justice Department »
Different state and local police departments around the country use different legal standards to get location data – some get warrants while others do not. In August 2011, ACLU affiliates filed FOIA 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.
Learn more about the ACLU’s national FOIA request »
One of the documents unearthed through the ACLU’s FOIA request is a Justice Department chart that reveals how long the top U.S. cell phone companies hold on to people’s private usage data, including location (cell tower) information, call and text message logs, and IP addresses.
See the DOJ's Cell Phone Company Data Retention Chart »
In July 2012, responding to a request from Reps. Edward Markey (D-Mass.) and Joe Barton (R-Texas), cell phone companies revealed that in 2011 alone they received approximately more than 1.2 million requests from police for customer information such as location or text message data. The ACLU has sent a letter to the CEO’s of the nation’s major cell phone providers asking them to stop routinely collecting and storing data on their customers’ daily movements.
License Plate Readers
Learn more about the automatic license plate scanners and the ACLU’s national FOIA requests »
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Learn more at dotRights.org: Location Information: Do You Know Where Your Privacy Is? (PDF) |




