The supreme court did not decide, however, whether police conduct a protected “search,” requiring a warrant, when obtaining and using cell phone location data from phone providers. Only three justices definitively declared that such action is a “search.”
The other justices either assumed that a “search” occurred to decide the case on other grounds, or ruled that deciding whether a “search” occurred was not necessary in this case. Thus, whether cell phone tracking data is protected is still an open question.
However, the justices did not agree on much else. As Justice David Prosser notes in a 53-page lead opinion, “[t]he court deeply divided on these issues as evidenced by a number of separate writings.” Four concurring opinions were filed, with one dissent.
The case began in 2009 when Subdiaz-Osorio (Subdiaz) fatally stabbed his brother in Kenosha. The two had been fighting. A knife wound eventually caused the brother’s death. Subdiaz, who is not a U.S. citizen, skipped town apparently heading for Mexico.
After speaking with witnesses, police believed that Subdiaz was probably heading for Mexico with the murder weapon and contacted his cell phone provider (Sprint Nextel) to identify his location through cell phone tracking data. Police did not get a warrant.
The tracking was successful and local authorities arrested Subdiaz in Arkansas, and Kenosha police went to Arkansas to question him. Subdiaz, in Spanish, asked how he could get an attorney. Police, questioning him in Spanish, said a lawyer would be provided and continued to question him. He was later extradited back to Wisconsin.
After the Kenosha County Circuit Court denied his motion to suppress evidence, Subdiaz, who was 27 at the time, pleaded guilty to first-degree reckless homicide.
The appeals court upheld the conviction, ruling that if the trial court improperly allowed certain evidence that should have been suppressed, the error was harmless because Subdiaz, beyond a reasonable doubt, would have pleaded guilty to the same charge.
A Wisconsin Supreme Court majority affirmed the appeals court, by a 6-1 vote. Only Chief Justice Shirley Abrahamson argued the appeals court ruling should be reversed.
Justice David Prosser wrote a lead opinion. He assumed, without deciding, that people have a reasonable expectation in cell phone location data that is protected by the Fourth Amendment’s prohibition on unreasonable searches and seizures.
“It is no small task to afford law enforcement officers and government agencies the leeway they need to keep citizens safe while ensuring that citizens retain a reasonable degree of privacy.” – Justice David Prosser
However, Justice Prosser concluded that police had probable cause to obtain a warrant, and exigent circumstances – the need to recover the potential murder weapon and capture a suspected murderer who was attempting to flee the country and was a threat to public safety – created an exception to the warrant requirement.
Justice Prosser noted privacy as the “pillar of freedom” that must not become a legal fiction “as our world becomes more interconnected and dangerous.”
“The privacy landscape is shifting as we embrace new technologies,” wrote Justice Prosser. “Electronic devices afford us great convenience and efficiency, but unless our law keeps pace with our technology, we will pay for the benefit of our gadgets in the currency of privacy.”
“It is no small task to afford law enforcement officers and government agencies the leeway they need to keep citizens safe while ensuring that citizens retain a reasonable degree of privacy,” Justice Prosser wrote.
Justice Prosser rejected the state’s argument that obtaining the cell phone tracking data was not a “search” requiring a warrant. The state argued that the Sprint policy said the company would disclose location data to law enforcement if there was an emergency.
The policy was “opaque” and even if it was clear, Justice Prosser said, “[i]t does not necessarily follow that law enforcement may lawfully seek and obtain the information without a court order or without satisfying the exigent circumstances exception.”
Justice Prosser noted that the exigent circumstances exception to the warrant requirement still requires police to have probable cause that immediate danger exists. In essence, Prosser suggested that cell phone policies cannot trump probable cause.
Assuming Subdiaz had an expectation of privacy in location data and assuming police conducted a warrantless “search,” Justice Prosser concluded that “the tracking of Subdiaz-Osorio’s cell phone location fell within the exigent circumstances exception. …”
Prosser also ruled that Subdiaz did not properly invoke a right to counsel when he said: “How can I do to get an attorney here because I don’t have enough to afford for one.”
“Subdiaz-Osorio asked how he could get an attorney, which could lead a reasonable offer to wonder whether Subdiaz-Osorio was affirmatively asking for counsel to be present during the custodial interrogation or simply inquiring about the procedure for how to obtain an attorney,” wrote Justice Prosser in the lead opinion.
Justice Bradley Concurs
Justice Ann Walsh Bradley concurred. She agreed with the dissent that tracking a cell phone’s location is indeed a “search” that is protected by the Fourth Amendment, and the warrantless search was not justified by the exigent circumstances exception.
However, like the court appeals, Justice Bradley argued that it was harmless error for the circuit court to deny Subdiaz’s motion to suppress evidence.
“There is no reasonable probability that the circuit court’s errors in denying the defendant’s suppression motion contributed to the conviction.”
Justice Crooks Concurs
Justice Patrick Crooks concurred. Like Justice Bradley and Chief Justice Abrahamson, Justice Crooks concluded that “a warrant is required for the search of a cell phone’s location.” However, Justice Crooks said a “good faith” exception applied.
“There is no allegation that there was clearly established law that police disregarded in the course of the investigation in this case,” Justice Crooks wrote.
“The actions of the police here show that the officers were acting in good faith, and, therefore, a good faith exception to the warrant requirement is appropriate here.”
Justice Roggensack Concurs
Justice Patience Roggensack, joined by Justice Annette Ziegler, agreed that the “exigent circumstances” exception applied. But she wrote separately to raise concerns that Justice Prosser’s “wide-ranging discussion” may foreclose future arguments.
The lead opinion “all but forecloses argument ‘that a search under the Fourth Amendment depends on the language in an individual’s cell phone policy’ or that the defendant’s disclosure of information to a third party shapes his expectation of privacy,” wrote Justice Roggensack, noting she did not wish to decide if a “search” occurred.
Justice Ziegler Concurs
Justice Annette Ziegler concurred, joined by Justices Roggensack and Justice Michael Gableman. Justice Ziegler, concurring with Roggensack, wrote separately to address a recent U.S. Supreme Court decision in Riley v. California, 134 S. Ct. 2473 (2014).
In that case, police searched the contents of a suspect’s cell phone without a warrant. The Court ruled that in general, police may not search digital information on a cell phone without a warrant. But its ruling was based on exigent circumstances.
“We have received no briefing or argument on the broader privacy questions that are addressed in the lead opinion or in Riley,” Justice Ziegler wrote.
“The technological implications of a broader approach are vast and difficult to predict, and we are generally obliged to decide our cases on the ‘narrowest possible grounds.’”
Chief Justice Abrahamson Dissents
Chief Justice Shirley Abrahamson was the lone dissenter. She said citizens have a right of privacy in their cell phone location data, and a warrant is always required. In addition, she said no exception applied to relieve police from the warrant requirement.
“Rather than dance around the issue of whether government access to cell phone location data in the instant cases is a search within the meaning of the Constitutions, I propose that the court address it head-on,” she wrote, noting a similar case, State v. Tate, 2014 WI 89, in which police also tracked a suspect’s cell site location.
“People do not buy cell phones to have them serve as government tracking devices,” the chief justice wrote. “I conclude that government access to cell phone location data in the instant cases, which involves invasive surveillance of an individual’s movements, is a search within the meaning of the Constitutions,” Chief Justice Abrahamson wrote.
In addition, the chief justice argued that the state did not meet its burden to prove that exigent circumstances existed to allow police to obtain the data without a warrant.
“The State failed to demonstrate that any of the three purported circumstances advanced by Justice Prosser’s lead opinion – threat to safety, risk of destruction of evidence, and increased likelihood of flight – existed with sufficient urgency to justify the privacy violation in the instant case,” she wrote, noting there was time to get a warrant.
She noted that if exigent circumstances applied to all cases involving a possibly armed individual who allegedly committed a violent crime, “exigent circumstances would exist in most criminal investigations and the warrant requirement would be rendered a nullity.”
The chief justice noted that three justices – herself, and Justices Bradley and Crooks – agreed that exigent circumstances did not exist in the present case.