In this appeal, we consider whether people have a constitutional right of privacy in cell-phone location information. Cell phones register or identify themselves with nearby cell towers every seven seconds. Cell providers collect data from those contacts, which allows carriers to locate cell phones on a real-time basis and to reconstruct a phone’s movement from recorded data. Those developments, in turn, raise questions about the right to privacy in the location of one’s cell phone.
Historically, the State Constitution has offered greater protection to New Jersey residents than the Fourth Amendment. 3Under settled New 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. See State v. Reid, 194 N.J. 386, 399 (2008). In addition, New Jersey case law continues to be guided by whether the government has violated an individual’s reasonable expectation of privacy.
Because we find that cell-phone users have a reasonable expectation of privacy in their cell-phone location information, and that police must obtain a search warrant before accessing that information, we reverse the judgment of the Appellate Division. To determine whether the emergency aid doctrine or some other exception to the warrant requirement applies to the facts of this case, we remand the matter to the Appellate Division for further proceedings.
For the reasons discussed, we conclude that Article I, Paragraph 7 of the New Jersey Constitution protects an individual’s privacy interest in the location of his or her cell phone. Users are reasonably entitled to expect confidentiality in the ever-increasing level of detail that cell phones can reveal about their lives. Because of the nature of the intrusion, and the corresponding, legitimate privacy interest at stake, we hold today that police must obtain a warrant based on a showing of probable cause, or qualify for an exception to the warrant requirement, to obtain tracking information through the use of a cell phone.
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Our ruling today is based solely on the State Constitution. We recognize that Jones and Smith [U.S. Supreme Court decisions interpreting the 4th Amendment to the U.S. Constitution], to the extent they apply,would not require a warrant in this case.
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