Canine Automobile Search
The Fourth Amendment of the United States Constitution, amongst other things, provides that a citizen has the right to be protected against unreasonable searches and seizure. In general, a law enforcement officer must have an articulable suspicion, a reasonable belief, that there is criminal activity going on, before a citizen can be subjected to a stop, whether by car or on foot. Before a citizen can be searched, police officer must have probable cause to believe a person is involved in criminal activity.
Without getting into too much detail, individuals in automobiles may find themselves being subjected to different rules. This is because of the clearly mobile nature of an automobile and the concern that evidence could be lost. The courts have recognized the potential problem this mobility can cause to a police officer, attempting to evaluate and investigate, whether he has discovered criminal activity. Case law will allow the officer a reasonable amount of time to conduct this evaluation.
The term to be familiar with here is "detention." When an officer pulls you over on the side of the road, you are being detained. What happens next is up to the officer and will depend on what he finds as he approaches the vehicle. The officer will be looking in your windows, will be looking in your eyes, will be listening for affirmative statements from the driver and any passengers, will be watching for fidgety movements and nervous behavior. These observations will be used to determine the next step whether your stop on the side of the road is brief or slightly delayed.
If you know anyone that you have an idea may have the occasion to travel with illegal substances in their possession, be clear with them, you must advise them against the practice immediately. Simply telling an officer that you do not wish to consent to a search of your vehicle is not going to get it done any longer. Case law, with a history beginning nearly 30 years ago now, states that officers may detain individuals for a reasonable amount of time, with "reasonable" being defined loosely.
Further, in most instances, it has been found “reasonable,” for a police officer to wait and continue to detain a suspect, while awaiting for a canine unit to arrive. Further still, the use of the dog to detect drug contraband in a suspect's vehicle is said not to constitute a search, so as to trigger a citizen’s Fourth Amendment protection. This means that the current case law does not believe that an individual has an expectation of privacy, in the air. A canine walking around a vehicle sniffing the air is not thought to intrude upon the defendant's right of privacy. Therefore, it is allowed and the evidence collected after the use of the dog is admissible.
Therefore, the best course of action is to not put yourself in this circumstance. Further, if you know anyone that does put themselves in the circumstance, advised him strongly against it.