Nearly all drivers are familiar with their obligations when stopped by police for a motor vehicle violation.  Specifically, you are required to produce identification, your license, registration and insurance.  Additionally, police may engage in behaviors which are reasonably related to the traffic violation.  

Your Obligations as a Passenger in a Vehicle Stopped by Police

In contrast to that of a driver, passengers in vehicles stopped by police may posses additional rights.  Specifically, unless police have a reasonable belief that a passenger is involved in or has been engaged in some type of criminal conduct, they may lawfully refuse to provide their identification.  Additionally, police may not prolong a traffic stop and engage in activities unrelated to the motor vehicle violation.  

The Case Law

In U.S. vs Landeros, the 9th Circuit Court of Appeals held that passengers in a car stopped by police don't have to identify themselves, This is true even in a state with a “stop and identify” law, and even if the initial stop of the car was legal

In Landeros, the defendant was one of the passengers in a car stopped by police for speeding on a road in Arizona. The stop was legal,  as was the demand for the driver's license.  However, the investigating officer commanded Mr. Landeros to provide his identification. When Mr. Landeros refused, he was removed from the automobile and subsequently arrested. The basis for his arrest was 

A.R.S 13-2412: “It is unlawful for a person, after being advised that the person's refusal to answer is unlawful, to fail or refuse to state the person's true full name on request of a peace officer who has lawfully detained the person based on reasonable suspicion that the person has committed, is committing or is about to commit a crime.

Arizona Law provides that “[a] person shall not willfully fail or refuse to comply with any lawful order or direction of a police officer invested by law with authority to direct, control or regulate traffic

When reviewing the officer's actions, the Court specifically noted that police cannot demand that a person identify themselves without some particularized reasonable suspicion that they are engaged in criminal activity.  Moreover, the Court held that the officers could not prolong the duration of the traffic stop to engage in activities which were not related to the mission of investigating a traffic violation.