Warrant Necessary to Obtain Cell Phone Tracking Data
The New Jersey Supreme Court held that government agents must obtain a warrant, supported by probable cause and issued by a neutral judicial authority, before obtaining cell phone tracking data (unless exceptional, exigent circumstances apply). State vs. Earls, A-53-11 (N.J. Sup. Ct., Jul. 18, 2013)(slip opinion).
In an insightful opinion, the unanimous court held:
- “[w]e therefore find that individuals have a reasonable expectation of privacy in the location of their cell phones under the [New Jersey] State Constitution.”*
- “[D]etails about the location of a cell phone can provide an intimate picture of one’s daily life.” 
- “Modern cell phones … blur the historical distinction between public and private areas [of life]….” 
- “[C]ell phone use has become an indispensable part of modern life.”
- “[C]ell phones are not meant to serve as tracking devices to locate their owners wherever they may be. People buy cell phones to communicate with others, to use the Internet, and for a growing number of other reasons. But no one buys a cell phone to share detailed information about their whereabouts with the police.”[31, emphasis added]
The opinion (portion dealing with privacy) concludes:
- “[T]he 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.” 
As the excepts above indicate, New Jersey recognizes that technology changes and that the outdated reliance on 50 year old “wire-tap” and “reasonable expectation of privacy” must adapt to modern conditions.
The opinion will likely be well-cited in other jurisdictions by advocates for stopping the abuse of cell phone records by government agents. However, the opinion carefully notes that the rationale, perhaps uniquely, applies due to New Jersey law and New Jersey constitutional construction. [See 19-30] First, New Jersey’s Constitution and judicial interpretation affords greater protections than the federal , Fourth Amendment—”On a number of occasions, this
Court has found that the State Constitution provides greater protection against unreasonable searches and seizures than the Fourth Amendment.”  Second, and more importantly considering other cases challenging government use of cell phone records, New Jersey law “does not turn on whether [an individual] is required to disclose information to third-party providers to obtain service…” —as is the current case under federal, judicial interpretation (see Smith v. Maryland, 442 U.S. 735 (1979)(holding that voluntary disclosure of records to a third party waives privacy interest). But following the New Jersey Supreme Court’s insightful analysis, the rationale and assumptions underlying Smith itself may wane. See [14-19, 30].
The opinion also provides a fairly concise synopsis of cell phone technologies and strongly emphasizes the vast changes in cell phone capabilities [14-19, 31-32]. Importantly, the Court notes that the technological capabilities themselves, as technologies, affect the analysis of privacy interests. [31-32] In other words, advances in the technologies require re-assessment, and perhaps radical re-assessment to reflect the radical advances in technical capabilities, rather than gradual analysis. The Court notes that the cell phone advances just since 2006 are significant and obviate reliance on old assumptions. [31-32]
In a nutshell, the opinion may provide the following insights:
- technologies must be assessed as technologies and recognize the extraordinary capabilities of the devices;
- courts must carefully analyze the rationales and underlying assumptions of prior case law, constitutional protections, and statutes before rotely invoking prior law; and
- simply requiring a warrant, with centuries of precedent, does not impede law enforcement (and the exigent circumstances exceptions to warrants adequately address any truly exceptional cases).
* Note: Digits enclosed in square brackets denote page numbers in the slip opinion. For example,  references page 6.