Can You Track Me Now? Not Without a Warrant!

Published: Aug. 26, 2011

Last Updated: Oct. 05, 2020

This week, Eastern District of New York Judge Nicholas Garaufis rejected an FBI effort to use an individual’s cell phone tower records to track his movements over a 113 day period without first obtaining a warrant based on probable cause. Judge Garaufis’ opinion stakes some new ground and draws a line in the sand in the battle over location privacy. The reasoning may have some influence on location tracking and the Fourth Amendment, as the United States Supreme Court considers GPS tracking this term, in United States v. Jones.

The issue of cell phone tracking has vast implications for Americans’ privacy.  According to CTIA — The Wireless Association, at the end of last year there were 302.9 million cell phone subscribers in the United States. All these handsets automatically scan for the cell tower that provides the best reception and, approximately every seven seconds, the phones register their location information within the network. The carriers can keep track of the registration information in order to identify the cell tower through which calls can be made and received, as well as monitor the strength of the telephone’s signal during the progress of the call which helps pinpoint location. As a regular matter, cell providers keep records of what tower a call was initiated through, what tower it was terminated from, and at what time, for billing purposes.

This data creates a rich picture of individuals’ movements, and with greater or lesser specificity, depending on the density of towers in a particular area. Federal law enforcement has long been using cell phone records to track individuals’ movements. The government’s position has been that for prospective or historical cell site information, it only need show that the information sought is “relevant and material” to an ongoing criminal investigation. Only in the past few years have courts begun to question whether the government has a right to this information on less than a probable cause showing.

The government has argued that the Fourth Amendment does not apply for two main reasons. First, two 1970’s era Supreme Court cases have held that people have no expectation of privacy in their movements in public places, and thus the Fourth Amendment allows officers to install tracking beepers in cans of chemicals and follow the signals so long as the items are not clearly in a private location. Thus, the government has asserted, and some courts have held, that the Fourth Amendment does not regulate technology-enhanced tracking except inside the home or other private space.

Second, the government has asserted that when users turn on their cell phones, they knowingly and voluntarily transmit their location to their cell phone providers and thereby lose any expectation of privacy. This was the Court’s holding with regards to bank records and dialed phone numbers in prior Fourth Amendment cases.

Judge Garaufis takes these two issues head on, and makes some normative arguments about why past precedent simply doesn’t answer constitutional questions raised by modern cell technology. In doing so, he redirects some of the arguments that civil libertarians have made when arguing for constitutional regulation of cell tracking. It remains to be seen if Garaufis’ path is a better way forward.

With regards to the beeper cases, Garaufis makes a distinction between technologies that help officers track someone’s movements from one place to another and “dragnet type law enforcement practices” such as “twenty-four hour surveillance of any citizen”, which the Supreme Court beeper cases specifically left open. The latter requires judicial supervision where the former may not. This was the conclusion the U.S. Court of Appeals for the District of Columbia reached in United States v. Maynard, a case which the Supreme Court recently granted cert and will review next term.  (Notably, the Ninth Circuit had reached the opposite conclusion in United States v. Pineda-Moreno.)

Moreover, Garaufis opined that cell tracking is not only a dragnet with regard to the particular subject, but also is a mass surveillance technology since so many individuals carry cell phones. This analysis is a direct reponse to the Seventh Circuit case of United States v. Garcia written by the very well-regarded Judge Richard Posner, which had rejected the warrant requirement for GPS tracking, but had opined that the Fourth Amendment may very well control mass-surveillance. Those of us familiar with tracking technology wondered how a court would consider the issue of mass surveillance, given that Fourth Amendment challenges usually come on a case by case basis in the context of motions to suppress in criminal matters, and that affected individuals may have no idea of the “mass” nature of the technology used or who else was affected.  Judge Garaufis notes the ubiquity of cell phones and opines that since cell-site-location records effectively enable “mass” or “wholesale” electronic surveillance, there’s greater reason for the Fourth Amendment to apply than in GPS tracking of a single car.

Garaufis then takes on the third party doctrine, wherein the government has successfully argued in several contexts, that information in the hands of intermediaries is not Fourth Amendment protected because the data is knowingly disclosed to third parties. In the past, courts have held that the contents of phone calls and letters, which are not already under surveillance by communications carriers, remain private, but that addressing information, which they provider uses to route the call or letter, does not.  In recent history, by drawing an uneasy analogy from phone calls and letters to the emails and instant messages (which, unlike calls and letters can be read in transit if not encrypted), courts have tended to extend Fourth Amendment protection to the contents of communications—the audio of a phone call or the text of an email—and not to transactional data about the communication, such as the IP address or number dialed. With a proliferation of location-based services, pro-privacy advocates have argued that this kind of data is actually content which requires a warrant, rather than metadata, which might not.

Applied to cell site tracking, the government has argued that individuals knowingly turn over their location information to the provider and thus have no Fourth Amendment rights in it. Some courts have held that, unlike dialed numbers which appear on your bill, subscribers are unaware that cell tower and sector information are collectable. This has been a shaky basis for constitutional protection, however, because the more people know how cell phones work, the less rights we have against warrantless tracking.

Judge Garaufis, however, rejected the knowledge-based waiver, and held instead that cumulative cell-site-location records are not subject to the third party doctrine. Garaufis rejects the content/non-content distinction which we’ve been relying on to protect communications in the hands of third parties. “There is no meaningful Fourth Amendment distinction between content and other forms of information, the disclosure of which to the Government would be equally intrusive and reveal information society values as private,” he writes. Rather, looking at language in the Supreme Court’s dialed numbers cases, Smith v. Maryland, Garaufis holds that “there are circumstances in which the legal interest being protected from government intrusion trumps any actual belief that it will remain private. In such cases, society’s recognition of a particular privacy right as important” trumps the third party doctrine. With regard to cell tracking, because “established normative privacy considerations support the conclusion that the reasonable expectation of privacy is preserved”, the Fourth Amendment requires a warrant.

Garaufis’ reasoning here could be called circular, and I’m sure other civil liberties advocates drew a sharp intake of breath in reading anything that could call into question the content/transactional information distinction (and thus lead, inadvertently, to diminished privacy for content). However, the hallmark of the Fourth Amendment is reasonableness and its purpose is to regulate the relationship of government to citizens. Moreso than most legal doctrines, the Fourth Amendment is guided by the ick factor, and this opinion by Judge Garaufis does much to pinpoint what’s disturbing about cell site location tracking and to tie it to existing court cases and to the pervasive and commonsensical concern about the balance of government power and individual rights in our technological age.