Court Approves Warrantless Use Of Police Anti-Terror Phone-Tracking Tech

A state supreme court has just approved the use of a special police counterterrorism phone tracking device without a warrant.

The Supreme Court of Wisconsin on Thursday released a decision retroactively approving Milwaukee police’ warrantless use of “stingray” tech — which allows police to intercept names, phone numbers, locations, call records, text messages and other private cellphone data — to locate a murder suspect. (RELATED: California Police Using Secret Anti-Terrorism, Phone-Tracking Tech For ‘Routine Police Work’)

According to an Ars Technica report, the court justified its approval based on a “related judicial order that essentially served the same purpose,” despite the lack of a specific warrant authorizing the device’s use. That order approved “the installation and use of a trap and trace device or process,” “the installation and use of a pen register device/process,” and “the release of subscriber information, incoming and outgoing call detail… and authorizing the identification of the physical location of a target cellular phone.”

Justice Patience Roggensack wrote the 5-2 majority decision for the case, and said the given order could be suitably viewed as a search warrant based on probable cause.

The suspect in question was apprehended in June 2009 after officers investigated a shooting that left one man dead and another wounded. Witnesses’ description of the shooter matched surveillance camera footage of a man who, on the same day of the shooting, bought a prepaid mobile phone for a store called Mother’s.

Milwaukee County’s district attorney then sought a court order to find the phone, which police identified as belonging to US Cellular’s network. They then used a stingray device to isolate the search to a single building, where they went door-to-door until eventually hitting the suspect’s mother’s apartment, where he was residing.

The suspect — Bobby L. Tate — tried to appeal the cellphone evidence three times based on the lack of a warrant, before ultimately losing in the state’s highest court.

Justices upheld a similar case in Kenosha against Nicolas Subdiaz-Osorio, who was convicted of homicide after police tracked his phone with the help of his service provider.

Citing the prior case, Chief Justice Shirley Abrahamson dissented with the court’s decision in the Tate case.

“Unlike the majority opinion in Tate and Justice Prosser’s lead opinion in Subdiaz-Osorio, I conclude that government access to cellphone location data in the present cases is a search within the meaning of the Constitutions that requires a warrant, and that the warrant must comply with the existing directly applicable statutes,” Abrahamson wrote.

“The warrant in Tate did not comply with the existing statutes and is invalid. No warrant was obtained in Subdiaz-Osorio.”

Abrahamson dissented in both cases, and said that the searches involving cellphone data in both cases should have required a search warrant, and that the resulting evidence presented in court should have been suppressed.

“Even in the majority opinion they based their limited discussion of the stingray to testimony from the trial court,” American Civil Liberties Union attorney Nathan Wessler told Ars. “They mischaracterized how a stingray works. Yes, it tracks just a specific subject, but, as you well know, it also sends out a signal to every phone in the area. They don’t fully understand the privacy implications of the technology.” (RELATED: After Feds Snatch Documents From Police Station, Judge Throws Out Phone Spying Case)

The state passed a new law earlier this year requiring probable cause-based warrants for cellphone tracking, which did not retroactively apply to Tate’s case.

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