BOSTON (CN) — The Massachusetts Supreme Court struggled Wednesday to reconcile arguments about police using cellphone location data to identify everyone who was in the vicinity of a crime when there are no suspects otherwise.
"Doesn’t society have an objective expectation that you’re not going to be caught up in a police search in this way," Justice Scott Kafker asked, noting that “the idea that 50,000 people are potential suspects is a bit much."
While the justices seemed to think the police met strict constitutional standards in this case, they also worried that allowing the government to indiscriminately sweep up location data for hundreds or thousands of innocent people could lead to a dystopian result.
“It’s a slippery slope,” said Justice Dalila Wendlandt. “You could find out if a person was home at 4 a.m., or if he was in a Catholic church at 10 a.m. on Sunday.”
She added: “If you had enough data points you could put together a very good picture of Justice Wendlandt’s private life.”
“You could see if a person was at a political event or other association,” fretted Justice David Lowy.
The case arose from a string of six similar armed robberies in the Boston area. Police had no suspects, but they got a warrant for a “cell tower dump” to identify the phone numbers of everyone in the area of the six robberies at the time — ultimately yielding 50,951 unique phone numbers.
After police found a number that was present at many of the crimes, Jerron Perry was indicted in October 2019. Perry faces murder charges because someone died in one of the robberies.
He aims to throw out the cellphone data, claiming it was scooped unconstitutionally because the police had no specific suspects and didn’t even have any reason to think that the perpetrator had a phone with him or used it to commit the crimes. A lower court rejected his motion in April 2021, and the state high court agreed to review it.
Although cellphone data is a 21st century issue, the briefs in the case went all the way back to Tudor England when police could be given a “general warrant” to rummage through anyone’s belongings, usually looking for “subversive” Catholic or Puritan literature. In the Colonial era, British officials were often given a similar right to forcibly enter people’s homes looking for untaxed goods.
The Founders wrote the Fourth Amendment in response, stating that warrants require probable cause and a specific description of what is being searched for.
Perry’s lawyers argued in their brief that what the state did here amounted to a general warrant with the goal of “obtaining a haystack in hopes of finding a needle.”
The ACLU filed an amicus brief arguing that cell tower data searches are an indiscriminate invasion of privacy. They are “inherently unreasonable because they constitute bulk surveillance [and] leave to the officers’ discretion how to manage the vast trove of private (but irrelevant) information that the government obtains,” the group claimed.
And an organization called the Surveillance Technology Oversight Project told the court that the nature of cell towers “will radically skew the precision of cell tower data for low-income communities [and] likely accelerate surveillance and over-policing of marginalized and multi-marginalized communities.”
That’s because many minority group members live in cities where cell towers are more densely packed, said Brian Owsley, a professor at the University of North Texas, Dallas College of Law, who has written several law review articles on cell tower searches.
The U.S. Supreme Court held in 2018 that many cellphone data searches require a warrant. In this case the police did get a warrant, so the question was how far police can legitimately go with a warrant.
