Score another victory for supporters of the Fourth Amendment right against unreasonable searches. This year’s term of the U.S. Supreme Court has been kind to supporters of the Fourth Amendment. The Court today held in a 6-3 decision that police may not extend a traffic stop in order to wait for drug-sniffing dogs when there is no probable cause to search the vehicle.

The Court’s majority opinion held “that a police stop exceeding the time needed to handle the matter for which the stop was made violates the Constitution’s shield against unreasonable searches.” As such, once a driver is pulled over for a traffic violation, and the matter is resolved either through the issuing of a citation or otherwise, the traffic stop must cease unless the officer has “probable cause” to believe that a canine search is warranted. As the court says, an officer’s authority to hold a driver and confront him “ends when the tasks tied to the traffic infraction are – or reasonably should have been – completed.”

Of course, “probable cause” can always be created by officers after-the-fact. And the Court said that officers are still allowed to use drug-sniffing dogs during the course of a routine traffic stop. This ruling simply states that they cannot extend the time of a traffic stop merely to call for a dog (assuming no probable cause exists). While that may sound complicated and convoluted, it is in the end another roadblock deterring police officers from violating your Fourth Amendment rights, and another weapon for attorneys to use in situations such as the one encountered by Dennys Rodriguez, the driver in this case.

This is pretty interesting case, and you can read the Court’s full opinion here.