What Is Probable Cause for a Vehicle Search With Police?

Police can generally search a vehicle at a traffic stop.

Police can legally search a vehicle if they have a valid warrant or probable cause to do so. Police may also be able to legally search a vehicle if the search is ancillary to a lawful arrest of one of the passengers. However, lack of probable cause will often render the results of a search inadmissible in court. Those with questions about the lawfulness of a vehicle search should seek legal counsel.

Probable Cause Requirement

For evidence found in a search to be admissible in court, the searching officer must have had either a valid warrant or probable cause to search. Probable cause is a standard considerably lower than certainty; the searching officer need only reasonably believe that evidence of a crime exists in the place to be searched. Judges likewise issue warrants based on a finding of probable cause. Certain exigent circumstances may also allow searches without satisfaction of probable cause.

Vehicle Searches

Courts have established numerous specialized probable cause rules for searches of vehicles, in recognition of the fact that vehicles' easy mobility presents special evidentiary problems. For instance, an officer making even a routine traffic stop may make a search of all areas to which the passengers of the car had access (so long as probable cause for the traffic stop itself was proper). If there has been no traffic stop but the officer reasonably believes that a vehicle contains evidence of a crime, he or she may search the entire vehicle (including trunks, locked compartments and any discrete containers of appropriate size for that evidence inside the vehicle). If an immediate search is not feasible, the officer may also impound the vehicle and search it later.

Vehicle Exceptions

Certain exceptions to the warrant requirement operate in the context of vehicle search. Should one of these exceptions apply, it effectively substitutes for probable cause analysis. For instance, if the owner of the vehicle consents to the search (or if the officer reasonably believes that the owner has evinced consent), the officer may search the vehicle without probable cause. Courts have also upheld vehicle searches without warrants or probable cause at the U.S. border (typically for drugs or illegal passengers). In all search contexts, officers may also search an area without a warrant if they see evidence of contraband in plain view (for example, a bag of marijuana sitting in the backseat of a car).

Objectivity

Probable cause analysis is objective, not subjective. Valid probable cause to search is not undermined by the fact that an officer may have had other motives for the search. For instance, in the case of Whren v. U.S., police pulled over defendants for a traffic violation, but defendants alleged that police had actually pulled them over based on an unsupported suspicion that there were drugs in the car. The Supreme Court found that, since the police had observed a valid traffic violation, they had probable cause to pull defendants over. Any contraband observed by police during the course of the traffic stop was therefore admissible in court, regardless of potential subjective motivations for the traffic stop.

Exclusion

Any search conducted without probable cause, a valid warrant or operation of some exception to the warrant requirement will be an illegal search under the Fourth Amendment. Any evidence seized in an illegal search will be inadmissible (not allowed as evidence) against the defendant in court. Occasionally, the law may make exceptions when law enforcement was acting under a good-faith belief that there was probable cause for the search (for instance, when a warrant is invalid on a technicality but police and prosecution were absolutely unaware of the flaw).

References

• "Criminal Procedure: Cases, Materials and Questions (Second Edition)"; Loewy, Arnold; 2006.
• Goliath/The Gale Group: The "Routine Traffic Stop" from Start to Finish
• Cornell University Law School: Whren v. United States (U.S. 2006)

Resources

• First District Appellate Project: Traffic Stops and Searches During Traffic Stops