Editor’s note: This article was published in the January/February 2012 print edition of Boston Review, before the Supreme Court’s January 23 decision in United States v. Jones. An update from the author follows the article.


During the Supreme Court’s last term, in the course of oral argument over the constitutionality of a California law that restricted the sale of violent video games to minors, Justice Samuel Alito interjected: “What Justice [Antonin] Scalia wants to know is what James Madison thought about video games.”

Of course Madison had no such thoughts, but the question perfectly captures the challenge that new technologies present to originalism, the theory that, when adjudicating constitutional questions, judges should rely essentially on how constitutional provisions were understood at the time of their enactment.

The Supreme Court is frequently called on to apply the Constitution to situations the framers could never have dreamed of. And when it comes to the Constitution, technology can cut in both directions. Sometimes, a new technology fits relatively easily into existing notions of constitutional protection, as it did in the video games case. Scalia’s opinion for the Court holds that video games qualify for First Amendment protection because they are a form of expression that communicates ideas, in part “through features distinctive to the medium.” Citing the Court’s decision in Burstyn v. Wilson (1952), which reached a similar conclusion with regard to movies, Scalia reminds us, “Whatever the challenges of applying the Constitution to ever-advancing technology, ‘the basic principles of freedom of speech and the press . . . do not vary’ when a new and different medium for communication appears.”

At other times, as with this term’s United States v. Jones, the use of new technologies poses important challenges to traditional understandings of constitutional protections. Jones involves the government’s covert placement of a GPS device on the undercarriage of a car owned by Antoine Jones, a nightclub proprietor in Washington, D.C. Police suspected Jones of distributing cocaine, and the device provided them a record of the car’s location and movement, every ten seconds for a month. At Jones’s trial, the prosecution used the record as evidence that his car had repeatedly traveled to a suspected “stash house” where large amounts of narcotics had been found. Jones’s counsel argued that the GPS data should not have been admitted at his trial. The Court must decide whether attaching a GPS device and gathering information from it constitutes a “search” or “seizure” within the meaning of the Fourth Amendment, which prohibits “unreasonable searches and seizures.” If using the GPS device amounted to search or seizure, then the government needed a valid warrant, which it did not have.

The government’s position in the case is straightforward: the Supreme Court has long held that Fourth Amendment protections are not triggered when the government looks at what a person “knowingly exposes to the public.” For example, police do not conduct a search when they tail a car on public roads or when they observe what any member of the public might, such as the aroma of marijuana surrounding a person on the street. In the government’s view, a GPS device is just a more mechanical, more reliable, cheaper way of doing something law enforcement officials have always been entitled to do.

But the new technology may mark a difference of kind—not just degree. Privacy was traditionally protected as much by practical constraints as by legal principles: the sheer cost of round-the-clock surveillance by teams of law enforcement agents meant that few people faced a realistic risk of being targeted. GPS slashes those costs to pennies a day. And because software can rapidly sift through the reams of data a GPS device produces, the new technology enables pervasive government monitoring.

If the Court concludes that the police use of a GPS device on Jones’s car did not constitute a search or seizure, then any law enforcement agency would be free to install GPS devices without warrants, probable cause to believe that criminal activity is afoot, or indeed any suspicion at all. At oral argument last term, the justices speculated that a state might simply attach a GPS device to every license plate it issues. And if law enforcement agents are free to attach GPS devices to people’s cars, why not to their parkas or raincoats? After all, these garments are “knowingly expose[d] to the public” much of the time. Several years ago, law professor Jack Balkin described a new form of governance that relies on pervasive information gathering and data mining as the “National Surveillance State.” The Jones case marks the Supreme Court’s first confrontation with the issues that will arise in such a state.

Perhaps seeking to persuade justices with a taste for originalism, Jones’s counsel argued that attaching a GPS device to someone’s car without their consent is a kind of trespass. That invocation of ancient understandings carried the day in Silverman v. United States (1961), in which the Court held that police use of a “spike microphone” that intruded “several inches” into the wall of a suspect’s house constituted a physical trespass and thus required a warrant. Slapping a GPS on someone’s car, in this view, is no different.

If planting a GPS unit on a car is not a search, then might a state simply install a GPS on every license plate it issues?

While this sort of argument might seem tempting, linking constitutional protections to traditional—physical—notions of property misses two critical points about the digital age.

First, informational privacy is becoming as vital as physical privacy. The problem in Jones’s case is not that the GPS intruded a fraction of an inch into the chassis of the car; it’s that the GPS provided a bounty of information about his life. The Court tackled a similar problem in Kyllo v. United States (2001). The decision held that police use of a thermal imaging device across the street from a suspect’s home constituted a search. No one worried that the device was somehow “stealing” the heat that emanated from the house, but the justices did care that the device was capable of revealing intimate details about a target’s life—the kinds of details the Fourth Amendment is intended to keep private. Scalia’s charmingly old-fashioned example of such protected details was the hour at which “the lady of the house takes her daily sauna and bath.”

Second, the information individuals want to keep private is, more and more often, in the hands of third parties. Protecting a person’s physical property does nothing to safeguard these data. Cases involving the Stored Communications Act—which allows federal prosecutors to access cell phone records with a lesser evidentiary showing than is required for conventional warrants—are working their way through the courts. Late last year a federal judge in Texas held that the Act’s standard for disclosure “is below that required for the Constitution.” Earlier, a federal court of appeals held similarly with regard to email.

Treating the use of GPS devices as a search or seizure, and thereby triggering the warrant requirement, would hardly hamstring the government, as Jones’s case itself shows. Investigators actually got a warrant because they convinced a magistrate that there was probable cause to believe Jones was involved in narcotics dealing. But instead of attaching the GPS unit within the required ten days and in the District of Columbia, agents waited eleven days and installed it while the car was in Maryland. Thanks to its bungling of the Jones case, the government might obtain a license to dispense with warrants in the future.

In many ways, the foundation of modern Fourth Amendment law is Justice Louis Brandeis’s dissent in Olmstead v. United States (1928). In explaining why wiretaps, even though they involved no trespass into the target’s home, should be treated as a search, Brandeis quotes the Court in Weems v. United States (1910):

Time works changes, brings into existence new conditions and purposes. Therefore a principle, to be vital, must be capable of wider application than the mischief which gave it birth. This is peculiarly true of constitutions.

And it is especially true of how we should understand the Fourth Amendment today.


UPDATE (January 30): On January 23, the Court issued its decision in Jones. Though the ruling was unanimous, the various opinions illustrate the complexity both of the specific questions—whether and how the Constitution restricts the government’s use of GPS devices—and of constitutional interpretation generally.

Justice Scalia’s opinion for the Court (joined by the Chief Justice Roberts, Justice Kennedy, Justice Thomas, and Justice Sotomayor), holds that the act of attaching a GPS device to a car and using it to monitor the car’s movements constitutes a search under the Fourth Amendment. His analysis is largely originalist: by putting the device on the car, the government physically intruded onto Jones’s personal property, and this kind of intrusion was understood, in the eighteenth century, as a search. Having anchored his opinion in traditional understandings of property, Scalia’s opinion mostly ignores the issues raised by modern information technology. Thus we have no greater clarity on whether the government could, following the hypothetical scenario I outline above, install GPS devices on license plates before issuing them, in which case the government would not have committed a trespass as that term was understood at the time the Fourth Amendment was ratified.

Justice Alito (joined by Justices Ginsburg, Breyer, and Kagan) concurred in the judgment—namely, that Jones had been subjected to a search—but strongly disagreed with Justice Scalia’s reasoning. Instead of grounding analysis of a “21st-century surveillance technique” in “18th-century tort law,” Alito relies on the framework laid out by the Court in its 1967 decision in Katz v. United States: does the government’s conduct violate “reasonable expectations of privacy”? Alito’s analysis is flexible: it recognizes that society’s expectations can morph over time in response to changes in technology and social understandings. He sees that modern technology undermines the practical constraints that traditionally protected privacy, as I argue above. Thus, for him, the long-term nature of the surveillance creates the Fourth Amendment problem. “Relatively short-term monitoring of a person’s movements on public streets,” presumably even when it involves a GPS device, is acceptable to Alito and the three justices who joined his concurrence. His approach thus provides a different sort of protection than Scalia’s, but not necessarily greater protection.

Finally, although Justice Sotomayor joined Justice Scalia’s opinion for the Court, she also wrote a separate concurring opinion. There, she stakes out the approach most concerned with protecting privacy. In cases involving “novel modes of surveillance that do not depend upon a physical invasion on property,” she observes, “the majority opinion’s trespassory test may provide little guidance.” She notes that even short-term GPS monitoring could provide the government with “a wealth of detail about [a person’s] familial, political, professional, religious, and sexual associations,”, which could be aggregated and mined years down the road, perhaps inhibiting the exercise of fundamental associational and expressive freedoms. And she expresses a willingness “to reconsider the premise”—long relied upon by the Court—“that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties.” If the Court followed her lead here, it would be more difficult for the government to gain access to individuals’ phone and bank records held by businesses.

In many ways, the decision in Jones was a victory for Fourth Amendment values: had the case been decided in the government’s favor, it would have been a disaster. But the ruling left open a host of important questions as well. Some are technical: Does the use of a GPS device invariably require a warrant based on a neutral magistrate’s finding of probable cause, or would some lesser standard, such as reasonable suspicion, suffice? Others are more fundamental. We are still left wondering, how should we understand privacy in an electronic age?

For readers who want a more detailed discussion of all the open issues, see Tom Goldstein’s debrief on SCOTUSBlog, “Reactions to Jones v. United States: The government fared much better than everyone realizes.”