A man carrying a gun and a cellphone entered a federal credit union in a small town in central Virginia in May 2019 and demanded cash.
He left with $195,000 in a bag and no clue to his identity. But his smartphone was keeping track of him.
What happened next could yield a landmark ruling from the Supreme Court on the 4th Amendment and its restrictions against “unreasonable searches.” The court will hear arguments on the issue on April 27.
Typically, police use tips or leads to find suspects, then seek a search warrant from a judge to enter a house or other private area to seize the evidence that can prove a crime.
Civil libertarians say the new “digital dragnets” work in reverse.
“It’s grab the data and search first. Suspicion later. That’s opposite of how our system has worked, and it’s really dangerous,” said Jake Laperruque, an attorney for the Center for Democracy &Technology.
But these new data scans can be effective in finding criminals.
Lacking leads in the Virginia bank robbery, a police detective turned to what one judge in the case called a “groundbreaking investigative tool … enabling the relentless collection of eerily precise location data.”
Cellphones can be tracked through towers, and Google stored this location history data for hundreds of millions of users. The detective sent Google a demand for information known as a “geofence warrant,” referring to a virtual fence around a particular geographic area at a specific time.
The officer sought phones that were within 150 yards of the bank during the hour of the robbery. He used that data to locate Okello Chatrie, then obtained a search warrant of his home where the cash and the holdup notes were found.
Chatrie entered a conditional guilty plea, but the Supreme Court will hear his appeal next week.
The justices agreed to decide whether geofence warrants violate the 4th Amendment.
The outcome may go beyond location tracking. At issue more broadly is the legal status of the vast amount of privately stored data that can be easily scanned.
This may include words or phrases found in Google searches or in emails. For example, investigators may want to know who searched for a particular address in the weeks before an arson or a murder took place there or who searched for information on making a particular type of bomb.
Judges are deeply divided on how this fits with the 4th Amendment.
Two years ago, the conservative U.S. Court of Appeals for the 5th Circuit in New Orleans ruled “geofence warrants are general warrants categorically prohibited by the 4th Amendment.”
Historians of the 4th Amendment say the constitutional ban on “unreasonable searches and seizures” arose from the anger in the American colonies over British officers using general warrants to search homes and stores even when they had no reason to suspect any particular person of wrongdoing.
The National Association of Criminal Defense Lawyers relies on that contention in opposing geofence warrants.
Its lawyers argued the government obtained Chatrie’s “private location information … with an unconstitutional general warrant that compelled Google to conduct a fishing expedition through millions of Google accounts, without any basis for believing that any one of them would contain incriminating evidence.”