Law enforcement agencies and privacy advocates are in a long-standing face-off that might finally be coming to a head. Tracking people using cellphone location data: Should it require a search warrant?
Yesterday, both sides were given the opportunity to argue their case as lawmakers consider bringing in new legislation to provide clarity on location privacy. For several years, confusion has surrounded the legal standard required for cops to track people by cellphone, with courts in different states issuing conflicting judgments. The Justice Department has continued to argue that Americans have “no protected privacy interest” over historic location data stored by carriers. But civil rights groups disagree—and in recent months, the issue has generated nationwide attention, following the revelation that major wireless carriers had received more than 1.3 million requests for subscriber data from law enforcement in 2011 alone. (The 1.3 million included requests for content of text messages, wiretaps, and geolocation information—sometimes as part of so-called “cell tower dumps” that involve carriers handing over data on all cell users that have connected to a tower during a specific period of time.)
In a House judiciary committee hearing Thursday, Peter Modafferi from the International Association of Chiefs of Police made the law enforcement case. Modafferi argued that warrantless cell tracking is necessary because it enables cops to develop leads, establish suspects, and confirm facts after a crime has been committed—in other words, it helps provide the “fundamental building blocks” in the early stages of an investigation, he said in a written statement. Changing the law so that cops would be forced to show probable cause and obtain a search warrant before obtaining historic cellphone location data, according to Modafferi, would hinder their ability to identify perpetrators of a crime and “make it significantly more difficult to solve crimes and seek justice for victims.”
However, Catherine Crump of the ACLU disagreed. The civil liberties advocate argued that a warrant requirement would impose “no unreasonable burden on the law enforcement agents” because they already have to obtain these “regularly and routinely for searches of homes, vehicles and email accounts.” Crump pointed out that the Justice Department recommends that its agents seek a warrant when tracking people in real time, but not when seeking historic location data for retrospective surveillance. The ACLU supports a piece of proposed legislation—the Geolocation Privacy and Surveillance Act—that would change this, applying the warrant standard to all forms of location data in most cases because, Crump said, “people have just as strong a privacy interest in where they have been in the past as they do in where they will go in the future.”
Former Justice Department senior counsel Mark Eckenwiler also contributed to the hearing, telling lawmakers that there were several areas in current law on location surveillance that were “not entirely satisfactory.” Eckenwiler warned that techniques used to conduct location monitoring had the potential to cause “significant, unjustified privacy invasions” of innocent citizens and recommended that the House committee consider bringing in safeguards to limit or even prohibit some of the more invasive location monitoring tactics. The former government official said in some cases law enforcement agencies were conducting warrantless location surveillance of any phone that had contact with a suspect, based on the “questionable assumption that even a single contact with the target phone constitutes evidence of criminal activity.” This was a “troubling practice,” he said.
While the House considers introducing new legislation on location tracking, some states have decided to take action into their own hands. As I reported here last month, Texas lawmakers have proposed a new amendment to the state criminal code that would in all but exceptional cases require the authorities to get a search warrant to obtain cellphone location information. Separately, parallel efforts to reform laws around email privacy are also marching ahead. This week the Senate Judiciary Committee voted unanimously to advance a bill that would update an aging surveillance law, removing a controversial loophole that allows authorities to gain access to Americans’ emails without a warrant if they are more than 180 days old.