Today, the Cyberlaw Clinic filed an amicus brief (pdf) on behalf of the Electronic Frontier Foundation in the Supreme Judicial Court of Massachusetts. The case is Commonwealth v. Augustine, and the issue is whether law enforcement officers can obtain someone’s cell phone location data without first obtaining a warrant.
Modern cell phone services make detailed records of a phone user’s travels, which are highly sought-after by law enforcement because they provide the unprecedented ability to retroactively determine where a phone user was, and when. This typically reveals information about a person’s friendships, religious preferences, shopping and eating habits, hobbies, and participation in community activities, as well as whether they were near any crime scenes.
We argue that the protections of the US and Massachusetts Constitutions prohibit law enforcement from warrantlessly poring over such records of people’s movements. Law enforcement officers must demonstrate probable cause to a neutral member of the judicial branch and act according to a valid warrant before such intense intrusion into people’s privacy is appropriate. Without demonstrating reason to believe that a crime has occurred and that the privacy intrusion is likely to provide specified information relating to the crime, the government has not met its burden, and traditional legal safeguards against overzealous or abusive investigations prevent it from intruding on the privacy of the individual in question.
The trial court agreed that a warrant was required for such information and rejected the application of the “third-party doctrine,” the theory that individuals give up their privacy interests in information voluntarily revealed to a third party such as a cell phone company. In our brief, we urge the Supreme Judicial Court to affirm the lower court’s judgment and protect the privacy of those in the Commonwealth of Massachusetts.
For those interested in hearing the parties present their arguments to the Court, oral argument is scheduled for October 10, 9AM, at the John Adams Courthouse, Courtroom One, Second Floor, Pemberton Square, Boston, MA 02108.
For more information and a discussion of the state of the law on location tracking in the United States, see EFF’s blog post regarding this case.
Image Credit: Figure 1A of Yves-Alexandre de Montjoye, César A. Hidalgo, Michel Verleysen, Vincent D. Blondel, Unique in the Crowd: The privacy bounds of human mobility, Scientific Reports, March 25, 2013; http://www.nature.com/srep/2013/130325/srep01376/full/srep01376.html; licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/