N.J. Supreme Court: Police Need Warrant for Your Cellphone Data

If you're in New Jersey, it has a just become a lot tougher for cops to get their hands on your cellphone location information.

In a landmark decision (.PDF) that seems to follow a rising tide towards more digital privacy protections, the New Jersey Supreme Court ruled that local law-enforcement needs a warrant to get their hands on a suspect's cellphone location data. This is the first time a state Supreme Court has recognized a Fourth Amendment protection of cellphone location data.

See also: DOJ Still Arguing It Doesn't Need Warrant To Track You With GPS

"Disclosure of cell-phone location information [...] can reveal a great deal of personal information about an individual," the ruling said. "With increasing accuracy, cell phones can now trace our daily movements and disclose not only where individuals are located at a point in time but also which shops, doctors, religious services, and political events they go to, and with whom they choose to associate."

The ruling only applies in the state of New Jersey, and the judges, who voted unanimously, used the higher privacy protections granted by New Jersey Constitution to justify their decision. But they also made a case that this was a necessary decision, given the times and the advancement of technology.

"The technology has evolved to the point where data is incredibly precise, and this historical records are going to become more and more precise over time," Alan Butler, an attorney for the Electronic Privacy Information Center, who litigated the case, told Mashable. Butler believes that this case will act as a precedent for other states to rule similarly in other cellphone tracking cases.

In similar cases in the past, the U.S. government has argued that cellphone location data falls under the scope of the so-called "third party doctrine," a legal rationale which claims that this kind of information is voluntarily handed over by the cellphone user to his or her provider. Hence, the user has no expectation of privacy regarding that data, which allows authorities to get it without probable cause and, consequently, without a judge-issued order.

But the New Jersey Supreme Court judges strongly refused that rationale.

"No one buys a cell phone to share detailed information about their whereabouts with the police," the ruling reads. "Although individuals may be generally aware that their phones can be tracked, most people do not realize the extent of modern tracking capabilities and reasonably do not expect law enforcement to convert their phones into precise, possibly continuous tracking tools."

Privacy and digital rights advocates hailed the ruling as the latest in a string of judicial and legislative victories.

Nathan Wessler, an ACLU staff attorney who is arguing in a similar case in Maryland, told Mashable that this decision "shows growing momentum toward protection of sensitive and private information about Americans' location and movements."

In late June, Montana passed a law that requires cops to get a warrant for both real-time as well as historical location data. A similar law was approved in Maine last week.

The case dates back to 2006, when suspect Thomas Earls was accused of a series of residential burglaries in Middletown, NJ. The local police were able to obtain his location data from T-Mobile without a warrant, nor any type of court order. T-Mobile collaborated with the Middletown Township Police Department, providing it with Earl's whereabouts at three different times on Jan. 26, 2006. The last location led to his arrest.

Privacy advocates hope that the decision in New Jersey, as well as the laws in Maine and Montana, will have a ripple effect on the national stage.

"As more state legislatures and courts require search warrants," Hanni Fakhoury, and Electronic Frontier Foundation activist told Mashable in an email, "hopefully the federal courts and Congress will see the writing on the wall and do the same."

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