Oftentimes the police, after stopping a motor vehicle for a motor vehicle infraction, will request permission from the operator to search the motor vehicle. Usually something will trigger the request, such as, the smell of marijuana or some kind of furtive movement on the part of the driver or passenger. Such conduct often leads the police to believe that criminal activity may be afoot, such as illicit drugs or illegal firearms. Without more evidence of criminal activity, the police have no cause to search the vehicle and the driver does not have to give permission to the police to search his or her vehicle. The police may inquire verbally but beyond that they have no further recourse.The police may go so far as to request the driver and any passengers to step from the motor vehicle. They may conduct a pat frisk of the person and then conduct a pat frisk of the motor vehicle. If the police find evidence of a crime and arrest is likely to ensue. Once that event occurs those involved can argue that they were subject to an illegal arrest (the exit order itself was illegal), and any items found on his person or in his or her car should be subject to a motion to suppress. The motion to suppress essentially precludes the police from using at trial any evidence it seizes from a defendant or the defendant's vehicle, because such evidence was obtained illegally. The police had no cause to ask anyone to exit the vehicle and no cause to conduct a search of the person or the vehicle.
Each case is different and each case has factors that may change the outcome of a motion to suppress. The courts may consider whether or not the area area where the stop occurred is a high crime area; whether the defendant is known to the police; whether there is information from an informant; whether an item was seen in plain view or whether the police testified that some kind of hand-to-hand transaction that took place at the car. These factors could change the outcome of the motion to suppress.
It is unwise for anyone stopped by a police officer to challenge the officer's authority and tell the officer what he or she is allowed to do. Let the officers do their job and if they make a mistake, a good attorney will find the error and suppress any evidence.