Can the police conduct an automobile search at a traffic stop or sobriety checkpoint?

A valid automobile search should be founded on several factors, including a basis for the traffic stop, a basis for continuing a detention beyond the traffic stop, and finally, probable cause for the officer to search the vehicle. If a driver pulls up to a valid DUI checkpoint or sobriety checkpoint, then a valid basis for the traffic stop exists. To justify an automobile search, an officer must demonstrate reasonable suspicion, probable cause, or an exception to either of those components.

Reasonable Suspicion and Probable Cause During a Traffic Stop

Very little is actually required to establish reasonable suspicion in order to justify an automobile search during a traffic stop. If the DUI checkpoint has been established to identify intoxicated drivers, then the officer will be allowed to make a basic inquiry into the driver’s sobriety. If the officer smells any odor of alcohol, then the driver can be removed from the vehicle and subjected to field sobriety tests. The officer can also run a warrant check, make sure a driver has a valid license, and verify insurance coverage. If during that process the officer observes something unusual, she can continue the detention to investigate further.

Once an officer continues a detention, she must quickly develop facts to justify further detention and probable cause for an automobile search. An officer cannot simply hold a driver captive for hours while trying to decide what to do. Factors that contribute to probable cause for a search may include an admission by a driver that a joint of marijuana is in the ashtray, the odor of marijuana coming from the inside of the car, or an officer observing open containers of beer in plain view.

There is no set number of factors necessary to justify a search, but the officer must develop something more than a suspicion that an offense has occurred or is about to occur. If available factors suggest a drug offense, then an officer has probable cause to search an automobile without a warrant. The search can cover any area of the vehicle where drugs might be stored, including the hood and trunk.

A Valid Automobile Search: Exceptions to the Search Warrant Requirement

If the officer thinks a driver is intoxicated, the officer can search the car for evidence of recent consumption, like empty liquor bottles. This is called the exigent circumstances exception to the warrant requirement. This exception allows officers to search just about every compartment of a car as long as they are not causing damage to the car.

If an officer cannot develop probable cause for an automobile search, he may still be authorized to search a car at a DUI checkpoint based on some other exception. The most frequent exception is called search incident to an arrest. If the officer decides that a driver is not intoxicated at the DUI checkpoint but learns that the driver has an outstanding arrest warrant, then the officer may be able to conduct an automobile search incident to a valid arrest. The officer must establish a link between the offense and the search. For example, if the outstanding warrant is for an armed robbery, then the officer could search the car for any weapons because there is a connection between the search for a gun and the nature of the offense. 

The second main exception to the probable cause requirement is an inventory search. Regardless of the reason for a driver’s arrest, if the officer’s department has an inventory policy, then the officer may search, or inventory, the driver’s vehicle consistent with that policy. If the inventory policy requires the officer to detail the contents of an automobile’s trunk and storage areas, then he can enter the trunk to inspect the contents.

Even though many people spend as much time in their cars as they do in their homes, automobiles do not share the same privacy protections as a house or apartment. A DUI traffic stop is frequently a starting point for law enforcement to tap into automobile search exceptions.