Illinois v. Caballes Case Brief

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.


  • Advocates: Ralph E. Meczyk argued the cause for Respondent Lisa Madigan argued the cause for Petitioner Christopher A. Wray argued the cause for Petitioner, on behalf of the the United States, as amicus curiae
  • Petitioner: Illinois
  • Respondent: Roy I. Caballes
  • DECIDED BY:Rehnquist Court
  • Location: –
Citation: 543 US 405 (2005)
Granted: Apr 5, 2004
Argued: Nov 10, 2004
Decided: Jan 24, 2005
Illinois v. Caballes Case Brief