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BENCH BLOG: A change in course at the high court

Two decisions reveal new methodology on Fourth Amendment searches

Jean DiMotto is a retired Milwaukee County Circuit Court judge. She served for 16 years, and was on the criminal bench for 12 of those years.

Judge Jean DiMotto retired in 2013 after 16 years on the Milwaukee County Circuit bench and now serves as a reserve judge.

The U.S. Supreme Court has changed course after nearly 50 years by deciding that the touchstone of Fourth Amendment jurisprudence is trespass to a property interest, not reasonable expectation of privacy.

Attachment of a GPS device

In United States v. Jones (2012) the high court considered whether a warrantless, nonconsensual attachment of a global positioning system device to the undercarriage of a vehicle for purposes of surveillance constituted a search within the meaning of the Fourth Amendment.

The GPS device was attached when the defendant’s Jeep Grand Cherokee was parked in a public lot. Over the four-week period of surveillance, more than 2,000 pages of data were obtained. Antoine Jones was indicted on charges of conspiracy to deal cocaine.

The district court suppressed only the data obtained when the Jeep was in Jones’ garage. In denying suppression of the remaining data, the court reasoned, consonant with Katz v. United States (1967), that Jones did not have a reasonable expectation of privacy in the location and movements of his Jeep on public streets.

Jones was and sentenced to life in prison. The U.S. Court of Appeals for the District of Columbia Circuit later reversed the district court, ruling that warrantless use of a GPS device violated the Fourth Amendment.

The case went on to the U.S. Supreme Court and Justice Antonin Scalia delivered the opinion of the court, joined by Chief Justice John Roberts and Justices Anthony Kennedy, Clarence Thomas and Sonia Sotomayer. In just 12 pages, the court held that the attachment of the GPS device to the Jeep and the subsequent monitoring of the device to obtain information was a search within the meaning of the Fourth Amendment.

In pertinent part the Fourth Amendment provides that the “right of the people to be secure in their persons, houses, papers and effects, against unreasonable searches and seizures, shall not be violated.”

Scalia’s analysis was that the vehicle was an “effect,” and that by installing the device, the government physically intruded on that effect for the purpose of obtaining information. Since the original meaning of the Fourth Amendment is property related and this was a trespass to property, the Fourth Amendment was violated.

The court asserted that while Katz added “reasonable expectation of privacy” to the reach of the Fourth Amendment, this augmented Fourth Amendment jurisprudence but did not supplant the threshold analysis of trespassory intrusion.

Drug-sniffing dog on the front porch

In spring 2013, the U.S. justices followed Jones with Florida v. Jardines.

In Jardines, the Miami-Dade Police Department received an unverified tip that Joelis Jardines was growing marijuana in his home. One month later the police arrived at the house with a trained drug-sniffing police dog on a leash.


The officer and dog approached the home on the front walkway. The dog alerted to the smell of narcotics and, as trained, moved about until it identified the front porch as the point of strongest odor. This took a minute or two. The officer and dog then left. A warrant was obtained based on the dog’s training and behavior, and a search of the home’s interior revealed marijuana plants.

Jardines successfully moved to suppress the plants on the grounds that the canine investigation was an unreasonable search. On discretionary appeal the Florida Court of Appeals reversed. The Florida Supreme Court in turn reversed the Court of Appeals.

The U.S. Supreme Court granted certiorari on the sole issue of whether the officer’s behavior with the dog was a search within the meaning of the Fourth Amendment. Scalia again authored the court’s opinion, a mere 10 pages, but this time was joined by Justices Ruth Bader Ginsburg, Elena Kagan, Sotomayer and Thomas.

Scalia noted that the curtilage of a house has long been protected by the Fourth Amendment, and here the officer entered and occupied the curtilage with the dog.

Customary social norms

Since the investigation took place in a constitutionally protected area, the next question was whether it permissibly occurred by “license” of the homeowner. It was nonconsensual, so it did not take place by explicit license.

Implicit license is determined by customary social norms.

Such social norms allow anyone, from friends to “solicitors, hawkers and peddlers of all kinds” to approach a front door and knock. Accordingly, a police officer may do the same, the court ruled, “precisely because that is ‘no more than any private citizen may do.’”

But customary social conventions do not invite front-door visitors to conduct a search. Thus, there was neither explicit nor implicit license from Jardines for the police officer to conduct a canine investigation on the curtilage. Accordingly, the Fourth Amendment was violated.

A concurrence by Kagan, joined by Ginsburg and Sotomayer, asserted that the case could just as easily have been decided under a Katz analysis since homeowners have a reasonable expectation of privacy on their front porches that excludes drug-sniffing dogs.

In the dissent, Justice Alito, joined by Roberts, Kennedy and Stephen Breyer, argued that domesticated dogs have existed for 12,000 years and with their keen sense of smell have been used for centuries by the police. Thus a dog on a front porch is within the scope of social norms.

Kagan’s concurrence responded that dogs trained to smell narcotics are recent additions to police work and do not fall within current social norms.

The dissent also noted the brief period of time involved: about two minutes. This tracks with Alioto’s concurrence in Jones where the only reason he joined the holding was that the surveillance of the Jeep lasted a full four weeks. A search, however, is not determined to be one based on an activity’s length but rather its substance – an impermissible boundary intrusion.

In the end, these two cases announce the court’s analytic methodology on whether a search occurred in violation of the Fourth Amendment. The threshold question is whether there was an impermissible intrusion on a property interest. If so, no further analysis is needed. If not, then a Katz analysis is undertaken: was there a reasonable expectation of privacy?

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