What did the ruling in US v. Rodriguez state about extending traffic stops?

The ruling in US v. Rodriguez clarified that law enforcement officers cannot extend the duration of a traffic stop beyond the time necessary to complete the initial purpose of the stop without reasonable suspicion of additional criminal activity. This means that once the legal reasons for the stop—such as checking a driver's license, vehicle registration, and issuing a citation—are complete, officers must have reasonable suspicion to continue detaining the individual for additional investigations, such as conducting a K9 sniff. This ruling emphasizes the importance of balancing the need for law enforcement to investigate criminal activities with the constitutional protections against unreasonable searches and seizures. Therefore, without reasonable suspicion, an extension of the traffic stop for a K9 sniff would violate the Fourth Amendment rights of the driver.