(Manuel Ribeiro)

SAN FRANCISCO — During arguments considering whether police need to show probable cause and obtain a warrant before getting a person’s cellphone location history, two members of a Ninth Circuit panel—Judges M. Margaret McKeown and Jay Bybee—expressed concern over the growing frequency and precision with which cellular providers can track their customers.

However, the third panel member, Senior Judge J. Clifford Wallace, pointed out that four other circuits that considered the same question held that Fourth Amendment protections don’t apply to regular business records that mobile phone companies keep that track customers’ location.

“There seems to be a swelling against your position,” Wallace said to American Civil Liberties Union lawyer Nathan Freed Wessler. “We have held that we don’t create a circuit split unless there’s a compelling reason to do so. Why is this case going to be able to be that exception?”

The case heard Friday springs from a 2016 decision from U.S. District Judge William Orrick III suppressing cell tower records obtained during a 2012 murder investigation. Although police had a warrant for the cell tower records, Orrick found the warrant application deficient and followed in the footsteps of two of his colleagues in the Northern District of California­—Judges Susan Illston and Lucy Koh—who have found that Fourth Amendment protections apply to the location information provided by mobile companies.

The federal appellate courts that have so far taken up the question­—the Fourth, Fifth, Sixth and Eleventh circuits­—have all found that since cell-site information is voluntarily handed over to a third party, it is subject to disclosure under a lower standard than probable cause. According to the ACLU, Friday’s case, United States v. Gilton, 16-10109, marks the first federal case in which the government has had to appeal a district court loss on the issue.

Arguing as a friend-of-the-court on Friday, the ACLU’s Wessler said police were able to access more than 9,000 data points collected over a 37-day period about defendant Antonio Gilton’s location without a valid warrant. Such long-term, “pervasive” surveillance, Wessler said, gave investigators a “virtual time machine” to track Gilton’s location.

Wallace, however, noted the government can obtain pen registers to track the numbers dialed by a suspect without a warrant as well as bank records. “Just because it starts out as someone thinking it’s private, doesn’t make it private,” Wallace said.

McKeown later pointed out that the cell-site location information contains no content of the defendant’s communications. But Wessler maintained that the records were “closely analogous to content information” due to the “very detailed” portrait they paint of a person’s life.

McKeown and Bybee, meanwhile, had pointed questions for the government’s lawyer, Jenny Ellickson of the Department of Justice’s Criminal Division, about what the further development in cellular companies’ tracking capacities might mean for the privacy implications of their records.

“What happens when [the companies are] able to pinpoint precise location?” asked Bybee, early in Ellickson’s presentation. Ellickson pointed to the seminal U.S. Supreme Court case, Smith v. Maryland, which held that the use of a pen register to track dialed numbers in a telephone doesn’t constitute a “search” under the Fourth Amendment.

“A pen register is not the same as someone being able to track your every movement,” said Bybee. McKeown, likewise, questioned whether consumers actually know what sort of information is being conveyed to cellular providers by the phone. “Given the difference of what’s happened in the digital world, how can you say that this information is voluntarily conveyed?”

Ellickson insisted that when information is voluntarily handed over to a third party like consumers hand over their location information to cellular providers “the granularity or the precision of the information does not matter.”

Ellickson conceded that consumers may not know technical specifics of how mobile providers track their whereabouts, but maintained they implicitly understand that they are disclosing their location.

“They know they are doing something that makes the cellphone provider able to find their phone in the world,” she said.

Contact the reporter at rtodd@alm.com. On Twitter @Ross_Todd.

SAN FRANCISCO — During arguments considering whether police need to show probable cause and obtain a warrant before getting a person’s cellphone location history, two members of a Ninth Circuit panel—Judges M. Margaret McKeown and Jay Bybee—expressed concern over the growing frequency and precision with which cellular providers can track their customers.

However, the third panel member, Senior Judge J. Clifford Wallace , pointed out that four other circuits that considered the same question held that Fourth Amendment protections don’t apply to regular business records that mobile phone companies keep that track customers’ location.

“There seems to be a swelling against your position,” Wallace said to American Civil Liberties Union lawyer Nathan Freed Wessler. “We have held that we don’t create a circuit split unless there’s a compelling reason to do so. Why is this case going to be able to be that exception?”

The case heard Friday springs from a 2016 decision from U.S. District Judge William Orrick III suppressing cell tower records obtained during a 2012 murder investigation. Although police had a warrant for the cell tower records, Orrick found the warrant application deficient and followed in the footsteps of two of his colleagues in the Northern District of California­—Judges Susan Illston and Lucy Koh—who have found that Fourth Amendment protections apply to the location information provided by mobile companies.

The federal appellate courts that have so far taken up the question­—the Fourth, Fifth, Sixth and Eleventh circuits­—have all found that since cell-site information is voluntarily handed over to a third party, it is subject to disclosure under a lower standard than probable cause. According to the ACLU, Friday’s case, United States v. Gilton, 16-10109, marks the first federal case in which the government has had to appeal a district court loss on the issue.

Arguing as a friend-of-the-court on Friday, the ACLU’s Wessler said police were able to access more than 9,000 data points collected over a 37-day period about defendant Antonio Gilton’s location without a valid warrant. Such long-term, “pervasive” surveillance, Wessler said, gave investigators a “virtual time machine” to track Gilton’s location.

Wallace, however, noted the government can obtain pen registers to track the numbers dialed by a suspect without a warrant as well as bank records. “Just because it starts out as someone thinking it’s private, doesn’t make it private,” Wallace said.

McKeown later pointed out that the cell-site location information contains no content of the defendant’s communications. But Wessler maintained that the records were “closely analogous to content information” due to the “very detailed” portrait they paint of a person’s life.

McKeown and Bybee, meanwhile, had pointed questions for the government’s lawyer, Jenny Ellickson of the Department of Justice’s Criminal Division, about what the further development in cellular companies’ tracking capacities might mean for the privacy implications of their records.

“What happens when [the companies are] able to pinpoint precise location?” asked Bybee, early in Ellickson’s presentation. Ellickson pointed to the seminal U.S. Supreme Court case, Smith v. Maryland, which held that the use of a pen register to track dialed numbers in a telephone doesn’t constitute a “search” under the Fourth Amendment.

“A pen register is not the same as someone being able to track your every movement,” said Bybee. McKeown, likewise, questioned whether consumers actually know what sort of information is being conveyed to cellular providers by the phone. “Given the difference of what’s happened in the digital world, how can you say that this information is voluntarily conveyed?”

Ellickson insisted that when information is voluntarily handed over to a third party like consumers hand over their location information to cellular providers “the granularity or the precision of the information does not matter.”

Ellickson conceded that consumers may not know technical specifics of how mobile providers track their whereabouts, but maintained they implicitly understand that they are disclosing their location.

“They know they are doing something that makes the cellphone provider able to find their phone in the world,” she said.

Contact the reporter at rtodd@alm.com. On Twitter @Ross_Todd.