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Cell phone tracking by police: 2 key court decisions explained

As this issue continues to evolve, do your best to keep informed on the latest developments

Recent Supreme Court decisions in two cases related to law enforcement and cell phones — a 2012 case on tracking suspects with a GPS and a 2014 case on cell phone searches — has left some police leaders and policy makers wondering what cops are actually allowed and empowered to do with regard to cell phone tracking. Here, we clear up some of that confusion.

In U.S. v. Jones (2012), the Supreme Court decided 9-0 that police violated the Fourth Amendment’s protection against “unreasonable search and seizures” when they surreptitiously installed a GPS tracking device on a car driven by a suspected drug dealer. Police initially obtained a warrant but installed the device after the warrant expired. The government argued no warrant was required.

Jones settled that police must get a warrant to install a GPS on a car. But, the “unanimous” decision contains a lot of disagreement that leaves unsettled whether police need a warrant to remotely track cell phones.

So let’s examine the Jones decision, which is really three opinions in one.

Yes, all nine Justices concluded installing a GPS on a car without a warrant violated the Fourth Amendment.

But they based that decision on different rationales.

Opinion #1
Five Justices opined the police committed a physical trespass clearly prohibited by the Fourth Amendment as it was conceived in the 18th century. But this slim majority expressly left open whether acquiring the same information through electronic means without trespassing was unconstitutional.

It’s the two concurring opinions in Jones that delve into 21st century technology.

Opinion #2
Justice Alito’s opinion, joined by three other Justices, mocks the majority’s reliance on 18th century trespass in a computerized, information age where unlimited information can be obtained electronically.

This group of four based its decision on a later Fourth Amendment standard established in Katz v. U.S. (2012). Katz extended the Fourth Amendment to include a broader protection of a person’s “reasonable expectation of privacy” against government intrusion.

Alito acknowledged that police surveillance in public places that produced the same information as a GPS was constitutional. But he added that in the past, the practicality of resource allocation limited such surveillance to exceptionally important investigations.

With the advent of GPS technology, police can now conduct constant surveillance cheaply, easily, and for run-of-the-mill cases. Therefore it must be limited by the law.

But Alito left open the question of short-term monitoring versus the long-term (four weeks) monitoring occurring in Jones. He suggested the Court might reach a different balance in location monitoring in “extraordinary offenses.”

Alito’s opinion provides no bright line for law enforcement. What constitutes short versus long term and what “extraordinary offenses” might justify long-term monitoring?

Opinion #3
Justice Sotomayor’s concurring opinion agreed with much of Alito’s concurrence. But she ventured further into 21st century technology and how it’s changing our notions about privacy and what expectations are reasonable.

She wrote that today’s technology may soon have the Court reconsidering the premise that a person has no reasonable expectation of privacy in information voluntarily disclosed to third parties.

“This approach is ill suited to the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks. People disclose the phone numbers that they dial or text to their cellular providers; the URLs that they visit and the email addresses with which they correspond to their Internet service providers; and the books, groceries, and medications they purchase to online retailers. … I for one doubt that people would accept without complaint the warrantless disclosure to the Government of [such information.]”

What About Remotely Tracking a Cell Phone?
International Mobile Subscriber Identity (IMSI) catchers let police track cell phone locations by mimicking an actual cell tower. The devices present a signal to cell phones in their range that cause the phones to try to register as if it were a real tower. That data can be used to triangulate a phone’s location — “Stingray” is the trade name of the dominant IMSI catcher marketed to law enforcement.

Whether police can use devices like Stingray to track cell phone locations may well be decided by the Supreme Court. We already have a split of opinion on the question in the lower courts.

Federal appeals court rules cell-site location is within subscriber’s reasonable expectation of privacy
Warrantless cell phone tracking is upheld

Cell Phones are Different
Just this summer, the Supreme Court held police cannot search an arrestee’s cell phone without a warrant.

In distinguishing cell phones from other items subject to a search incident to arrest – like a wallet — the Court noted all the personal information contained in a cell phone.

The ACLU is making a comparable argument in cell phone tracking cases. It argues that unlike a GPS device on a car, a cell phone’s location enables the Government to track a person in their home.

Moreover, location data can reveal information.

In a YouTube video entitled Meet Jack. Or, What the Government Could Do with that Location Data the ACLU is also taking their argument to the court of public opinion.

Arguing that location data can reveal information about a person’s political and religious beliefs, sexual habits, etc., the ACLU taps into a concern expressed in Sotomayor’s concurrence in Jones as well as that of most citizens.

Legislatures May Decide
Justice Alito suggested in Jones that Congress and states are in a better position to relegate electronic location tracking. That’s what Congress did when it promptly regulated wiretapping after the Katz decision.

Montana made history last year by becoming the first state to broaden its warrant requirement to include cell phone location information and social media check-ins.

Maine’s legislature quickly followed suit by similarly requiring a warrant for cell phone location data, overriding the Governor’s veto.

GPS tracking in general and cell phone tracking in particular remain a bit of a moving target, so as this issue continues to evolve, do your level best to keep informed on the latest developments.

As a state and federal prosecutor, Val’s trial work was featured on ABC’S PRIMETIME LIVE, Discovery Channel’s Justice Files, in USA Today, The National Enquirer and REDBOOK. Described by Calibre Press as “the indisputable master of entertrainment,” Val is now an international law enforcement trainer and writer. She’s had hundreds of articles published online and in print. She appears in person and on TV, radio, and video productions. When she’s not working, Val can be found flying her airplane with her retriever, a shotgun, a fly rod, and high aspirations. Contact Val at