American Civil Liberties Union attorney Nathan Wessler speaks outside the Supreme Court on Wednesday, Nov. 29, 2017, in Washington, following arguments in a case about the government's ability to track Americans' movements through collection of their cellphone information. Chief Justice John Roberts and the court's four liberal justices indicated they could side with Wessler and extend the Constitution's protection against unreasonable searches to police collection of cellphone tower information that has become an important tool in the investigation of crimes. (Photo: AP/Jessica Gresko)

Thousands of geolocation points, obtained without a probable cause warrant, which helped convict a Chicago man of a string of violent crimes in 2011, are the focus of one of the latest cases before the U.S. Supreme Court.

Carpenter v. United States could impact virtually every criminal investigation of the future, deciding whether a trove of digital forensic evidence will be readily available to law enforcement—or would be subject to legal warrants.

The justices heard oral arguments on Wednesday, and questioned attorneys from both sides: the U.S. deputy solicitor general on behalf of the government, and an attorney for the American Civil Liberties Union on behalf of the petitioner, Timothy Carpenter, a man currently serving a term of 116 years in prison for his role in a series of armed robberies in the Midwest.

The new electronic frontier was clear by some of the comments from the justices, as reported by multiple witnesses in attendance.

“This is an open box. We know not where we go,” said Justice Stephen Breyer.

After 80 minutes of arguments, some indicated that the highest court in the U.S. may impose some kinds of restrictions, as the Associated Press and other reported. The four liberal justices and Chief Justice John Roberts appeared open to extending Constitutional protections against unreasonable searches under the Fourth Amendment.


The prosecutors who secured Carpenter's conviction, and the federal authorities who have successfully fought appeals, contend that four months of the suspect’s whereabouts collected from cellphone towers (cell site location information, or CSLI) was not subject to warrant.

The records, they maintain, were taken from a third party: the cellphone companies. So Carpenter was essentially never searched, they contend.

Carpenter and three others were arrested by the Detroit Police Department and accused of robbing a series of Radio Shack and T-Mobile stores. They were accused of herding customers and employees at the establishments to the back of the store at gunpoint, and ordering some workers to stuff their bags with new smartphones. They would flee with the devices, then dispose of their guns and getaway car, and sell the stolen phones. Carpenter was accused of organizing the operations, supplying the guns, and acting as a lookout, according to court documents.

One of the four suspects admitted his role in eight different robberies spanning Michigan and Ohio, according to court documents. After the confession, an assistant U.S. attorney submitted three applications for orders to access 152 days of cellphone records for Carpenter and the other individuals. The application was made under the Stored Communications Act, signed into law in 1986—and specifically did not seek warrants for the data.

All three applications were granted—notably the order directing MetroPCS, Carpenter’s phone provider, to comply. They produced 186 total pages of locations spanning 127 days, according to court filings. An FBI agent testified at trial that the data placed Carpenter near four of the armed robberies at the times they were committed. Carpenter was ultimately convicted and sentenced to six robberies under the Hobbs Act.

The FBI agent who testified at trial said also that the tower information was only recorded when the robbers were making a call, and that records were not created when “the phone is just in (a) pocket.”

The federal prosecutors maintain now that the appeals court upheld Congress’ intent in the Stored Communications Act to “strike a balance” by requiring detectives to “show ‘reasonable grounds’ but not ‘probable cause’” to obtain the cell site records.

The cell records are “not more sensitive than the records of phone numbers dialed and banking records” that are already regularly used in investigations, they argue. There is no “search” or “seizure,” since the records are already on file with the third-party cellphone companies.


But there was dissent when the U.S. Sixth Circuit upheld the decision on appeal in 2012.

“I do not think that treating the CSLI obtained as a ‘business record’ and applying that test addresses our circuit’s stated concern regarding long-term, comprehensive tracking of an individual’s location without a warrant,” wrote U.S. District Judge Jane Stranch.

“Police officers could have, for example, interviewed witnesses, sought security camera footage, or examined store receipts near the scene of a crime,” the ACLU writes in its brief, filed in August. “But these tactics pale in comparison to the unprecedented surveillance time machine that CSLI provides.”

The ACLU argues people have no choice in the 21st century but to have a cellphone for personal and professional use.

The civil rights group also points to a previous case, U.S. v. Antoine Jones, which decided that the long-term monitoring of a suspected drug trafficker using a GPS tracker did indeed constitute a “search” under the Fourth Amendment—and that police had overreached.


Justice Elena Kagan pointed toward what she called an “obvious similarity” between the previous Jones case and the current Carpenter arguments, according to multiple accounts of the proceedings.

Chief Justice Roberts, on the other hand, contended that the government’s argument was inconsistent with Riley v. California, a 2014 SCOTUS decision that held investigators had to get a warrant to search the cellphone of an arrestee.

Suggesting that an exception to the “third-party” doctrine must be established, Justice Sonia Sotomayor pointed toward medical records—which can’t be taken from hospitals or doctors without a patient’s consent.

Justice Samuel Alito, on the other hand, pointed out that bank records are potentially even more sensitive—and they are readily available to law enforcement.

Breyer, again, summed up the debate among the nine justices.

“How do we draw the line?” he asked the U.S. deputy solicitor general, at one point.

The case is being closely scrutinized by both law enforcement advocates and privacy experts. More than a dozen organizations filed amici curiae briefs to lend their voices to the proceedings, a group including the Electronic Frontier Foundation, the Institute for Justice, the U.S. Justice Foundation, Restore the Fourth, Inc. and the National District Attorneys Association, among others.

U.S. Supreme Court cases generally take months to be decided. Typically, the opinions are published before the SCOTUS summer recess, beginning in late June or early July.