Illinois v. Caballes

RESPONDENT: Roy I. Caballes
LOCATION: Texas State Capitol

DOCKET NO.: 03-923
DECIDED BY: Rehnquist Court (1986-2005)
LOWER COURT: Supreme Court of Illinois

CITATION: 543 US 405 (2005)
GRANTED: Apr 05, 2004
ARGUED: Nov 10, 2004
DECIDED: Jan 24, 2005

Christopher A. Wray - argued the cause for Petitioner, on behalf of the the United States, as amicus curiae
Lisa Madigan - argued the cause for Petitioner
Ralph E. Meczyk - argued the cause for Respondent

Facts of the case

During a routine traffic stop, a drug-detection dog alerted police to marijuana in Roy Caballes' car trunk. An Illinois court convicted Caballes of cannabis trafficking. Caballes appealed and argued the search violated his Fourth Amendment right to be free from unreasonable searches and seizures. The state appellate court affirmed the conviction. The Illinois Supreme Court reversed and ruled police performed the canine sniff without specific and articulable facts to support its use, "unjustifiably enlarging the scope of a routine traffic stop into a drug investigation."


Does the Fourth Amendment's search and seizure clause require a reasonable articulable suspicion to conduct a canine sniff during a routine traffic stop?

Media for Illinois v. Caballes

Audio Transcription for Oral Argument - November 10, 2004 in Illinois v. Caballes

Audio Transcription for Opinion Announcement - January 24, 2005 in Illinois v. Caballes

Sandra Day O'Connor:

I also have an opinion to announce in 03-923, Illinois versus Caballes that was authored by Justice Stevens.

This is a case that comes to us from the Supreme Court of Illinois.

In the opinion, authored by Justice Stevens, we answer a narrow question, whether the Fourth Amendment requires reasonable, articulable suspicion to justify using a drug detection dog to sniff a vehicle during a legitimate traffic stop.

An Illinois state trooper stopped petitioner Caballes for speeding on an interstate highway.

When the officer radioed the police dispatcher to report the traffic stop, a member of the State’s Drug Interdiction Team overheard the transmission and drove to the scene along with his narcotics-detection dog.

On arrival and while the first trooper was writing the warning ticket for speeding, the drug interdiction officer walked the dog around Caballes’ car, the dog alerted at the trunk prompting the officers to open the trunk where they discovered marijuana.

Caballes was arrested and charged with a narcotics offense.

The trial judge denied the motion to suppress the seized evidence.

The court found no Fourth Amendment violation because the officers did not unnecessarily prolong the traffic stop in order to conduct the dog sniff and because the particular dog sniff was sufficiently reliable to establishe probable cause to search the trunk.

The Illinois Supreme Court reversed.

In its view the use of a narcotics-detection cog converted the citizen police encounter from a lawful traffic stop into a drug investigation and because the shifting purpose was not supported by any reasonable suspicion of drug activity, it was unlawful.

We granted certiorari to review the Illinois Supreme Court’s holding.

We now vacate and remand.

In our view, conducting a dog sniff would not change the character of a lawful traffic stop unless the dog sniffs itself infringed unconstitutionally protected privacy interest.

Our cases made clear that it did not.

To fall within the purviews of the Fourth Amendment, police conduct must compromise a legitimate, interest in privacy.

Because a canine sniffs by a well-trained drug detection dog does not itself reveal noncontraband items and because any interest in possessing contraband cannot be deemed legitimate, the use of a properly trained drug detection dog during a lawful traffic stop will not generally implicate legitimate privacy interest.

In this case the traffic stop was lawful.

It was not prolonged beyond the time reasonably required to issue a warning ticket.

In these circumstances, a dog sniff that only reveals the presence of the substance no individual has any right to possess does not violate the Fourth Amendment.

Accordingly, the judgment of the Supreme Court of Illinois is vacated.

The case is remanded for proceedings not inconsistent with the Court’s opinion.

Justice Ginsburg and Justice Souter have filed dissenting opinions.