United States v. Jones

Following is the case brief for United States v. Jones, 132 S. Ct. 945 (2012).

Case Summary of United States v. Jones:

  • Police placed a GPS device on defendant’s car without a warrant.  The evidence gathered was used in a trial that resulted in defendant’s conviction.
  • The Court of Appeals reversed the conviction on Fourth Amendment grounds.
  • The U.S. Supreme Court affirmed.  The Court held that the police attaching a GPS device to defendant’s car to monitor the car’s movements on public streets was a search within the meaning of the Fourth Amendment.

United States v. Jones Case Brief

Statement of the Facts:

Police suspected Antoine Jones of engaging in drug-related crimes and applied for a warrant to place a global-positioning-system tracking device (GPS) on Jones’s car.  The warrant they obtained required it to be executed within 10 days in the District of Columbia.  The police, however, placed the GPS on his car 11 days later in Maryland.

Over the next month, police gathered information about all of Jones’s movements from the GPS.  That evidence was then used to obtain an indictment against Jones for drug crimes.  Jones moved to suppress the GPS evidence.  The trial court did not suppress any of the GPS evidence showing Jones’s car in public places, finding that Jones had no reasonable expectation of privacy when his car was in public.  Although his first trial resulted in a hung jury, Jones was found guilty at his second trial.  The trial court sentenced Jones to life in prison.

Procedural History:

The District Court convicted Jones of various drug crimes.  On appeal, the D.C. Circuit Court of Appeals reversed the conviction, holding that the warrantless use of the GPS violated the Fourth Amendment.  The D.C. Circuit Court of Appeals refused a rehearing en banc.  The U.S. Supreme Court granted certiorari.

Issue and Holding:

Does the warrantless attachment of a GPS device on a person’s car, and use of that device to monitor that car’s movements on public streets, violate the Fourth Amendment?  Yes.


The D.C. Circuit Court of Appeals decisions is affirmed.

Rule of Law or Legal Principle Applied:

The Government’s use of a GPS device to track a person’s car on public streets constitutes a search within the meaning of the Fourth Amendment.


Writing for the Court, Justice Scalia reasoned that Jones’s car is a personal “effect.”  Thus, by the terms of the Fourth Amendment — “the right of the people to be secure in their … effects” — attaching a GPS to the car to obtain evidence was a search.  Justice Scalia emphasized that such a trespass on an area specified in the text of the Fourth Amendment would be considered a search at the time the Amendment was originally adopted.

Justice Scalia noted that the “reasonable expectation of privacy” standard that resulted from the Court’s decision in Katz v. United States, 389 U.S. 347 (1967), does not replace the trespass-based understanding of the Fourth Amendment, but rather adds to it.

Concurring Opinion (Sotomayor):

Justice Sotomayor joined the majority because she agreed with Justice Scalia that the Katz standard augmented, rather than replaced, the trespass-based understanding of whether a search has occurred. Justice Sotomayor, however, also agreed with Justice Alito that modern technology now makes surveillance possible without physical invasion on property.  Accordingly, Justice Scalia’s trespass-based test provides little guidance.  The reasonable expectation of privacy analysis must consider the capabilities of new technology.

Concurring Opinion (Alito):

Justice Alito (joined by Justices Ginsberg, Breyer, and Kagan) concurred in the judgment, but disagreed with the Court’s reliance on Jones’s trespassory interest.  Justice Alito found that the use of a trespass-based analysis in the context of modern GPS technology was unwise, artificial, and strained the language of the Fourth Amendment.

Rather, Justice Alito would have relied on the reasonable expectation of privacy analysis in Katz to decide the case.  GPS technology allows law enforcement to monitor a person’s movements for long periods of time in ways they never could have done before (or at least not without great cost).  Accordingly, the warrantless GPS monitoring, over a four-week period, in this case violated society’s reasonable expectations of privacy.


The significance of United States v. Jones lies in the back and forth between reliance on the trespass-based standard and the reasonable expectation of privacy standard of the Court’s Fourth Amendment jurisprudence.  Justice Scalia favored an “originalist” approach by relying on the trespass-based standard, while acknowledging the viability of the Katz standard.

The other Justices, however, went right to the heart of the new challenges that modern technology presents.  The concurring justices noted that the act of putting a device on a car, and finding that to be the “search,” really misses the larger Fourth Amendment point.  GPS devices that track a person’s every movement reveals massive amounts of private information about a person.

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