(b) The Arizona Court of Appeals recognized that, initially, Johnson was lawfully detained incident to the legitimate stop of the vehicle in which he was a passenger, but concluded that once Officer Trevizo began questioning him on a matter unrelated to the traffic stop, patdown authority ceased to exist, absent reasonable suspicion that Johnson had engaged, or was about to engage, in criminal activity. The court portrayed the interrogation as consensual, and, Johnson emphasizes, Trevizo testified that Johnson could have refused to exit the vehicle and to submit to the patdown. But Trevizo also testified that she never advised Johnson he did not have to answer her questions or otherwise cooperate with her. A lawful roadside stop begins when a vehicle is pulled over for investigation of a traffic violation. The temporary seizure of driver and passengers ordinarily continues, and remains reasonable, for the duration of the stop. Normally, the stop ends when the police have no further need to control the scene, and inform the driver and passengers they are free to leave. An officers inquiries into matters unrelated to the justification for the traffic stop do not convert the encounter into something other than a lawful seizure, so long as the inquiries do not measurably extend the stops duration.