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Case preview: The cops and your cellphone records

October 30, 2017 | by Scott Bomboy

In late November, the Supreme Court will tackle a very modern question about the venerable Fourth Amendment: Does it allow police to see where you’ve been for the past four months by looking at your cellphone data without a warrant?

In Carpenter v. United States, the Justices will evaluate what seems to be a simple question with broad implications, and a controversy going back to a Supreme Court decision in 1979. In the case of Smith v. Maryland, the controversy in 1979 was about a device called a “pen register” that recorded all the phone numbers dialed from a phone account. The Court said that since a phone owner voluntarily allowed the phone company to record his or her outgoing call numbers, there was no expectation of privacy for the person making the calls.

Justice Harry Blackmun, writing for the 5-3 majority in Smith, rejected the argument that law enforcement officers needed a search warrant to get a phone company to record and send to them phone numbers dialed by a criminal suspect. Blackmun reasoned that Smith, the suspect, voluntarily gave those numbers to a third-party, the phone company, and the Fourth Amendment warrant requirement didn’t apply to the phone company because it retained the numbers in its normal business records.

In his dissent, Justice Potter Stewart said that information indicated by the phone numbers revealed personal information, and a warrant would be needed in the same way law enforcement would need one to listen to a private phone conversation.

The Smith decision has been challenged in many ways over the years and into the modern era, where cell tower data indicates the physical location where calls are made, along with the numbers dialed by the phone’s user.

In the Carpenter case, which will be argued on November 29, the cell number data placed a robbery suspect, Timothy Ivory Carpenter, near the scenes of several crimes, and at about the same time as those crimes happened.  The phone information was used as evidence leading to Carpenter’s conviction on robbery charges and he is serving a very long prison sentence.

Also in Carpenter’s case, federal agents gathered the information based on three court orders of a kind that do not require a search warrant and proof suggesting a crime. Under the Stored Communications Act of 1986, law enforcement officials can access cellphone tower information if it might be linked to a criminal investigation – a significantly less demanding standard than normally needed to get a warrant under the Fourth Amendment.

The U.S. Court of Appeals for the Sixth Circuit ruled against Carpenter and said the Fourth Amendment’s search warrant requirement only protects what was actually said in phone conversations. And it upheld the third-party doctrine that the phone records belong to the phone company, they aren’t private information, and they are needed to maintain the viability of cell tower phone service.

Carpenter’s lawyers believe modern cellphone records are fundamentally different than the old phones used in the 1979 Smith decision, especially since the records obtained by law enforcement showed Carpenter’s physical location over a four-month period. Carpenter is citing a more recent Court decision from 2012, United States v. Jones, that said a person has some Fourth Amendment privacy rights related to the use of GPS devices by law enforcement to track the location of a car.

In the Jones decision, Justice Antonin Scalia wrote for a unanimous court that police didn’t have a right to physically place the GPS on the unknowing subject’s car without a warrant and the police committed an act of trespass. Justice Samuel Alito agreed with Scalia’s overall reasoning but he also voiced concerns about other unsettled issues. “The Court’s reliance on the law of trespass will present particularly vexing problems in cases involving surveillance that is carried out by making electronic, as opposed to physical, contact with the item to be tracked,” Alito said.

The Carpenter case has spurred a flurry of activity among Fourth Amendment scholars on both sides of the issue, while the Justice Department is supporting the Sixth Circuit decision.

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