In State v. Earls, the New Jersey Supreme Court held that cell-phone users have a reasonable expectation of privacy for location information collected by cell-phone providers and that the police must obtain a search warrant before access that information. 214 70 A.3d 630, 633 (N.J. 2013).
In Earls, the police were investigating a burglary. As part of the investigation, the police searched for the defendant and his girlfriend, whose safety was in question. Id. at 632. The police requested information about the location of the defendant from T-mobile on three occasions based on a cell-phone they suspected he was using. Id. at 633. The police did not seek a warrant or a court order for the three traces. Id. at 634. T-mobile provided the information in the form of general location information (e.g. Highway 35 in Eatontown). Id. at 633.
The New Jersey Supreme Court held that cell-phone users have a “reasonable expectation of privacy in the location of their cell phones under the State Constitution.” Id. at 632. The court commented that consumers do not buy cell phones as tracking devices and don’t expect the government to use them in that manner. Id.
State law proved to be a key aspect of the privacy protection for two reasons. First, the New Jersey State Constitution has historically offered greater protection than the Fourth Amendment. Id. Second, under Ney Jersey law, “individuals do not lose their right to privacy simply because they have to give information to a third-party provider, like a phone company or bank, to get service.” Id.
The second aspect was one argument against protecting historical cell phone data in the Fifth Circuit. In re Application of the United States for Historical Cell Site Data, 724 F.3d 600, 613 (5th Cir. 2013) (“[T]he Government also has presented evidence that cell service providers’ and subscribers’ contractual terms of service and providers’ privacy policies expressly state that a provider uses a subscriber’s location information to route his cell phone calls).
Thus, state law may remain the best way for consumers to advocate for protecting their privacy rights regarding cell phone location data.