The Virginia Supreme Court on Friday ruled that police may not search vehicle passengers without a specific reason to believe that they may have committed a crime. The case began on April 19, 2006 when Suffolk police officers pulled over a car with four people on board at around 3pm.

Once stopped on the side of the road, Officer J.B. Carr used his drug-sniffing dog, Xanto, to check the vehicle in question. Xanto "alerted by sitting and waiting for his reward" on the rear passenger's side. Officer Jay Quigley ordered the vehicle's occupants out so that the car could be thoroughly searched. Nothing was found.

The police officers then proceeded to search the driver and two of the passengers. Nothing was found. Finally, passenger Travis Stacey Whitehead was searched and officers discovered two syringes and a bottle cap later identified as containing heroin residue. Whitehead was convicted of drug possession and sentenced to serve twenty-two months in jail.

Whitehead appealed, insisting that police cannot simply search every passenger of a vehicle without individualized probable cause for each person examined. He added that police had no reason to suspect him of criminal activity. The Virginia Court of Appeals upheld the conviction, stating that the process of elimination pointed to Whitehead's guilt. The high court disagreed.

"After the positive alert by the trained narcotics detection dog, Officer Quigley unquestionably had probable cause to search the vehicle," Justice Cynthia D. Kinser wrote. "However, without something more, the positive alert did not provide probable cause sufficiently particularized as to Whitehead to allow the search of his person."

The high court examined US Supreme Court precedent on the matter which established the principle that mere proximity to criminal activity does not constitute probable cause justifying a warrantless search. The case law suggested that establishing a common criminal enterprise between the passengers would have been one way to meet the constitutional standard for a proper search.

"The Commonwealth presented no evidence, other than Whitehead's status as a passenger in the vehicle, indicating that Whitehead and the other passengers were involved in any common enterprise involving criminal activity," Kinser wrote. "There also was no evidence indicating Whitehead individually was committing, had committed, or was about to commit a criminal offense."

The court found that the police had a strong suspicion after the drug dog alerted, but that it was just as likely that the dog had responded to an "old odor," as his handler admitted in court testimony. Performing a search on this weak basis violated the Fourth Amendment, the court found. Courts in Idaho, Illinois and Maryland have also ruled that a drug dog alert is not sufficient to justify the arrest and search of passengers.

The Virginia Supreme Court ordered the case against Whitehead dismissed. A copy of the ruling is available in a 60k PDF file at the source link below.