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Judge to Feds: To Track Cell Phones, Get a Warrant

Law enforcement agents must get a warrant to access cell phone location records
Catherine Crump,
Staff Attorney,
ACLU Speech, Privacy and Technology Project
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November 17, 2011

In a victory for the privacy rights of everyone with a cell phone, a court has held that law enforcement agents must get a warrant to access cell phone location records. The ACLU, ACLU of Texas and Electronic Frontier Foundation submitted a brief urging the court to adopt exactly this position. The Constitution requires nothing less.

In the case, the government asked for 60 days’ worth of records about where certain cell phones had traveled. It conceded that it had not demonstrated probable cause. A magistrate judge denied the government's request, writing that the Fourth Amendment sets probable cause as the constitutional minimum. It noted that “[t]wo months’ worth of hourly tracking data will inevitably reveal a rich slice of the user’s life, activities, and associations.”

The government appealed this decision, the government and the ACLU and its allies filed briefs and, yesterday, a federal judge in the Southern District of Texas issued an order upholding the earlier decision finding that the government violates the Fourth Amendment when it seeks historical location records from cell phone companies absent a warrant based on probable cause.

This is the right decision. As another court noted in the related context of the government attaching a GPS device to a car and tracking it for 28 days:

A person who knows all of another’s travels can deduce whether he is a weekly churchgoer, a heavy drinker, a regular at the gym, an unfaithful husband, an outpatient receiving medical treatment, an associate of particular individuals or political groups — and not just one such fact about a person, but all such facts.

We shouldn’t have to choose between using technology and keeping control of our private information. The ACLU is strongly committed to ensuring that as technology advances, our civil liberties are not left behind. That is why we founded the , and why 35 ACLU affiliates filed over 380 requests to learn about how local law enforcement agencies are using cell phones to track us. A consequence of having a cell phone should not include revealing to curious government agents one’s every movement. The Constitution protects all of us from unreasonable searches and seizures. Requiring the government to get a warrant before obtaining our location information means that a judge will make sure that this powerful new technology is not abused.

Join us in demanding that our privacy laws keep up with new technology; ask Congress to modernize the outdated “Electronic Communications Privacy Act” (ECPA) today!

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