Two weeks ago, in United States v. Jones, the United States Supreme Court unanimously held that police had performed a Fourth Amendment search when they attached a Global Positioning System device (GPS) to a suspect’s car, without a valid search warrant, and then used the device to monitor the car’s movements for four weeks.
Though the Court’s decision was unanimous, the rationale for it was not, and the divisions among the Justices as to the best rationale might prove to be almost as important as the decision itself. The Justices offer two distinct narratives about why the officers’ conduct in this case constituted a search. Both the clash, and the overlap, between these two narratives may signal a significant development in Fourth Amendment doctrine.
The Katz Revolution
In 1967, in Katz v. United States, a man named Charles Katz brought an appeal of his criminal conviction to the U.S. Supreme Court, to complain of what he believed was a Fourth Amendment violation. Katz had spoken on a public telephone while, unbeknownst to him, a listening and recording device had been attached to the telephone booth and was transmitting and preserving his words. Police had installed the listening and recording device because they suspected Katz of engaging in interstate gambling activities in violation of federal law, but they did not obtain a warrant. Based on Katz’s words, as recorded by the device, he was convicted of transmitting wagering information by telephone across state lines, a federal crime. Katz appealed the conviction and alleged that he had suffered a violation of his Fourth Amendment rights.
At the time, Katz had every reason to believe that he would lose his case. The Supreme Court had previously held in the 1928 decision of Olmstead v. United States that wiretaps which entailed no physical trespass upon any property belonging to the defendant inflicted no Fourth Amendment harm. Charles Katz was not even at home when the claimed violation occurred, and the attached recording and listening device did not invade the physical space of the telephone booth in which he had made his call. Yet, with the deck thus stacked against him, Charles Katz went on to win big. The Supreme Court reversed the judgment of conviction and overruled Olmstead, holding that the police had indeed violated Katz’s Fourth Amendment rights.
The Court announced in Katz that the government need not physically trespass on property to implicate the Fourth Amendment right against unreasonable searches and seizures. Furthermore, the fact that telephone booths do not appear in the precise list of protected items in the Fourth Amendment—which by its terms covers “persons, houses, papers, and effects”—did not stop the Court from condemning the agents’ use of a listening and recording device as unconstitutional. The new test for what would count as a Fourth Amendment search, as described in Justice Harlan’s Katz concurrence and as adopted by a majority in later cases, would be whether police had invaded any “reasonable expectation of privacy.” And wiretaps, the Court concluded, represented such an invasion.
In the wake of Katz, some expected that great changes in Fourth Amendment law would ensue. And the Court did revisit some of its older precedents and established some new ones. But most of the new cases made it clear that any promise that Katz had truly revolutionized the Fourth Amendment would remain largely unfulfilled, as the breadth of Fourth Amendment protection failed to expand substantially.
Some examples of Supreme Court cases evidencing how surprisingly little difference Katz had made are as follows: when the police wire an informant with a transmitter and thereby listen to our words as we confide privately in that informant, ignorant of the wire, police implicate no reasonable expectation of privacy (United States v. White, decided just four years after Katz); when police rummage through garbage that we have left at the curb for pickup, they are not engaged in a Fourth Amendment search (California v. Greenwood); when police fly over our curtilage (the area immediately around a house, if it is enclosed and made otherwise inaccessible to the public) in airplanes (California v. Ciraolo) or in helicopters (Florida v. Riley) and visually examine our belongings there, they perform no Fourth Amendment search; and when the government subpoenas records of our financial transactions from a bank (United States v. Miller) or arranges through the telephone company for the recording of all numbers called from our phones (Smith v. Maryland), it similarly inflicts no Fourth Amendment invasion of privacy. Significantly, in each of these cases, the government has refrained from physically trespassing upon a suspect’s property.
One might have thought that the decision in Katz would have led at least some of these cases to come out the other way, under a regime in which reasonable expectations of privacy—rather than physical trespasses on “persons, houses, papers, and effects”—determine the scope of the Fourth Amendment. Yet this did not happen.
Had police walked onto the curtilage in Ciraolo and Riley, instead of flying overhead in a plane or helicopter, they would have had to get a warrant. And had the bag of garbage at issue in Greenwood rested just inside the curtilage, not yet ready for collection, then rummaging through that bag would have qualified as a search. We could apply similar analyses to the other cases listed above as well.
Notions of physical trespass thus persisted in Fourth Amendment doctrine, even in contexts that seemed to implicate primarily non-property-based privacy expectations. For example, if you want privacy from prying eyes in your enclosed and covered backyard, this interest does not vanish merely because the person belonging to the prying eyes is seated on a helicopter hovering overhead, rather than standing just inside the entrance to your yard. As was the case with Charles Katz and his private telephone conversation, the location of the equipment that enables surveillance in these cases seems like it ought to be less important than the surveillance itself and the freedom that people would generally enjoy against such surveillance if the government did not deploy it.
The Fourth Amendment and the Tracking of Cars
In United States v. Knotts, a 1983 case, the Supreme Court first evaluated the Fourth Amendment implications of electronic tracking devices. The tracking device at issue in Knotts was a rudimentary beeper that emitted periodic signals that could be picked up by a radio receiver. The beeper could augment a pursuing officer’s ability to follow a suspect successfully. In Knotts, police arranged to have such a beeper placed inside a piece of property prior to its anticipated purchase by their suspect. This meant that the original owner of the property had consented to the placement of the device, and the suspect purchased property that already contained the beeper.
At the time, the Court ruled that this use of the beeper did not implicate any Fourth Amendment rights because a person lacks a reasonable expectation of privacy in the location of her car on the public streets. Just as police do not “search” a person merely by following him, the Court reasoned that the beeper that police used simply facilitated their following of the suspect and did nothing to turn that non-search pursuit into a Fourth Amendment search.
Though I have elsewhere criticized the ruling in Knotts, it had some logical force: since anyone might see you on the street or even follow you in her car, you could not plausibly claim to have an expectation of privacy against being located on public streets by the police during a particular journey.
Notably, however, the Court left unanswered the question of how far this logic would go, quoting the respondent’s worry that “the result of the holding sought by the Government would be that ‘twenty-four hour surveillance of any citizen of this country will be possible, without judicial knowledge or supervision.’” The Court responded to this concern by putting off the question, remarking that “if such dragnet-type law enforcement practices as respondent envisions should eventually occur, there will be time enough then to determine whether different constitutional principles may be applicable.”
With the advent of the GPS—and the case of United States v. Jones, which the Court just decided—we have arrived at the very scenario that the Court reserved for another day.
Part Two in this series of columns will appear here on Justia’s Verdict next Wednesday, February 15. –Ed.