Cell Phone Location Data and (Almost) The Fourth Amendment

From the Jurist (via the CrimProf Blog):

The New Jersey Supreme Court [official website] ruled [opinion, PDF] Thursday that police must obtain search warrants before obtaining tracking information from cell phone providers. The unanimous ruling marks the first time a state supreme court has recognized a Fourth Amendment [Cornell LII backgrounder] protection for cell phone location data. In the decision, Chief Justice Stuart Rabner noted that cellphone tracking technology has the potential to violate a person's privacy rights and must be subject to judicial review. Rabner also noted that no warrants will be required in emergency situations.

I recognize that this is an interesting issue and that the case highlights an important division in jurisdictions on whether the Fourth Amendment applies to cell phone location data.  This post is incorrect, however, to claim that the New Jersey Supreme Court recognized a Fourth Amendment protection for cell phone location data.  While the opinion nicely summarizes the relevant federal Fourth Amendment case law, pages 33-34 of the opinion make it very clear that the decision is based solely on Article I, Paragraph 7 of the state constitution, which has historically been the basis for greater protections than the Fourth Amendment (26).

Despite the opinion’s basis in state, rather than federal, constitutional law, the opinion contains good discussion regarding the rise of cell phone use and why users reasonably expect the locations of their cell phones to be private.