The case, formally known as United States v. Jones, has its roots in the technologically distant past of 2005, when smart phones, tablets, mobile apps, social networking and license plate cameras had not yet become ubiquitous—when it was still possible to make a trip to the grocery store without leaving a megabits-long trail of digital footprints.
The question before the Court turned in significant part on the physical trespass involved in placing a GPS tracker on a suspect’s car. Nowhere is this clearer than in the majority opinion, delivered by Justice Antonin Scalia, explaining why the Court ruled against the government (pdf):
However, the majority opinion stops well short of addressing the most pressing privacy issues that accompany today’s location tracking technologies. First, there are many more ways today to perform surveillance without physically trespassing on private property, a point explicitly recognized by Justice Samuel Alito in a concurrence joined by three other justices. And, as Justice Sonia Sotomayor wrote in another concurring opinion (pdf), “the Fourth Amendment is not concerned only with trespassory intrusions on property.”
Second, the assumption that tracking a person’s location requires advance planning and action is fast becoming outdated. Increasingly, and likely irreversibly, to be engaged in the world means leaving detailed digital records of almost everything we do.
In the past it would have been impractical to archive all of this information. Not anymore. Retail hard drive costs are over one million times cheaper today than in the mid-1980’s, and currently stand at roughly 5 cents per gigabyte. About $50 worth of storage can hold the information identifying the location of each of one million people to 4.5-meter accuracy at five-minute intervals, 24 hours a day for a full year. Data from video surveillance cameras is more voluminous, but storage cost trends are making it easier to archive that information as well.
In the future, therefore, the issue of before-the-fact location-tracking warrants will be largely irrelevant. All of the necessary data will be collected automatically. The important privacy questions will instead concern the protections that apply to that data: Who can see it? And under what circumstances?
The government certainly needs the ability to access archived information about the movements of a person credibly believed to be planning, for example, a terrorist attack. But what about juveniles suspected of petty crimes? What types of location data should be available to parents engaged in a child custody battle? Or former business partners embroiled in a legal dispute?
The Supreme Court has not yet addressed these questions. But, inevitably, it will. And the answers, far more than the ruling in United States v. Jones, will help define the meaning of privacy in 21st-century America.
Image by Thomas Hawk on Flickr
