Vehicle Searches Under the Fourth Amendment

The Fourth Amendment protects us from "unreasonable searches and seizures." This generally means the government and its agents, such as police officers, must obtain a search warrant before searching a person or their property. The text of the Fourth Amendment states:

“The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

However, when police officers have probable cause to believe a motor vehicle contains illegal contraband, they can bypass the warrant requirement to prevent the destruction or loss of evidence.

Motor Vehicles and the Fourth Amendment

Motor vehicles carry a lesser expectation of privacy because they are movable by nature and likely to quickly be taken out of a jurisdiction while officers obtain a warrant. Indeed, the U.S. Supreme Court has established multiple exceptions to the warrant requirement for vehicle searches.

However, the Supreme Court has recognized an automobile exception because motor vehicles, unlike your home, are movable. The ability to easily move a vehicle from one jurisdiction to another creates a sense of urgency the courts often refer to as “exigency.”

The Evolution of the "Automobile Exception"

The Court established the automobile exception in Carroll v. United States. In this case, prohibition agents stopped and searched the respondent’s motor vehicle while he was driving on a known smuggling route. The agents had unsuccessfully attempted to purchase illegal whiskey from him on a different occasion. This time, the agents found 68 bottles of illegal whiskey.

The Court found the warrantless search was permissible because, given the circumstances, obtaining a warrant was impractical. Carroll not only evaded authorities before in his vehicle, but the Court found the agents had probable cause to believe he was transporting illegal contraband.

The Court determined that the readily moveable nature of contraband in an automobile increases the urgency of searching a vehicle where officers have probable cause and a reasonable belief of criminal activity. Further, there is a lesser expectation of privacy in vehicles when compared to searching a home or office.

When Is a Warrantless Search Justifiable in a Traffic Stop?

Drivers do not have to consent to a search of their car at a traffic stop. However, as explained above in Carroll, police officers can initiate a stop and search the car if they have probable cause.

This is the legal basis required before police can arrest you or obtain a warrant to search or seize your property. Probable cause refers to a reasonable belief of a crime or traffic violation, grounded in specific facts or circumstances, like an officer's observations or a credible tip from an informant.

For example, highway patrol may set up a DUI checkpoint due to an increase in drunk driving accidents. Someone is stopped at a checkpoint, and the officer observes:

• Slurred speech
• Alcohol on the driver's breath
• An open liquor container

In that case, the officer has a reasonable suspicion they are driving under the influence. This is sufficient probable cause to perform a search without a warrant.

Supreme Court Cases on Vehicle Searches

There are several key Supreme Court decisions that impact vehicle searches, the scope of searches to passengers, containers, and compartments, and who has standing to challenge the constitutionality of a stop or search.

To start, the automobile exception does not just apply to emergency situations. According to the Court in Maryland v. Dyson, probable cause is sufficient, and the automobile exception does not require a separate finding of exigent circumstances.

In United States v. Ross, Officers received a tip from an informant that respondent Ross was selling drugs, which he kept in the trunk of a car. Officers stopped and arrested Ross, and when one officer opened the car trunk, he discovered heroin in a brown paper bag. An officer drove the car to the police station, where a second search was conducted, uncovering a large amount of cash.

The Court upheld both searches because, under the automobile exception, the officers lawfully stopped the vehicle based on probable cause and concealed contraband. Further, “where police officers have probable cause to search an entire vehicle, they may conduct a warrantless search of every part of the vehicle and its contents as thoroughly as a magistrate could authorize by warrant.”

Searches Incident to Arrest

The search incident to arrest exception allows officers to search an arrestee and areas within their immediate control for officer safety. Initially, in New York v. Belton, the Court held that an officer’s search of the vehicle after arresting the occupants and securing the scene, including the entire passenger compartment and closed containers, was reasonable.

But, in Arizona v. Gant, the Court narrowed this rule. Officers may only search a vehicle incident to arrest if it’s reasonable to believe the arrestee might access the vehicle at the time of the search or is within reaching distance of the passenger compartment.

In Coolidge v. New Hampshire the Court found the seizure of a car in a driveway is not justifiable as an incident to an arrest of a suspect in their home. Further, quoting Preston v. United States, impounding a car to effectuate an investigative warrantless search is unreasonable.

Further, per Knowles v. Iowa, officers cannot perform a vehicle search incident unless they exercise their discretion to arrest the driver instead of issuing a citation.

Mobile Homes and Curtilage

Mobile homes present an interesting gray area for vehicle searches. In California v. Carney, the Court found that the automobile exception applies when the mobile home is being used on the highway or parked in an area not typically used for residential purposes.

However, the Court has held that the automobile exception does not allow police officers to enter a person’s home or curtilage to search their vehicle. The curtilage is the area attached to and surrounding the home, and it falls under the protection of the Fourth Amendment. Collins v. Virginia clarified the automobile exception does not allow a “warrantless entry of a home or its curtilage in order to search a vehicle therein.”

Inventory Searches

In Cardwell v. Lewis, the suspect’s vehicle matched one seen leaving a crime scene that sustained front-end damage and was subsequently repaired. Police officers impounded the suspect’s parked car after his arrest and conducted a warrantless examination, confirming a match in paint samples and tire impressions.

The Court determined an examination of the car’s exterior based on probable cause of its involvement in a crime did not infringe on the suspect’s privacy. The suspect drove the car on public roads in plain view, and the interior, which contains personal effects, was not searched.

South Dakota v. Opperman further underscored the principle that vehicles have a lesser expectation of privacy than a home or office. The Court found an inventory search of an impounded car is a reasonable caretaking function for public safety and to account for a defendant’s property and personal effects. If the police find illegal contraband, such as drugs, during the inventory search as part of standard police procedure, it is admissible in the trial court.

Passengers

Motorists are not the only people who may become the subject of a police search. In Maryland v. Wilson, the Court found it reasonable for law enforcement officers to order passengers to exit a vehicle during a traffic stop. This not only promotes officer safety, but the intrusion on passengers is minimal.

In Rakas v. Illinois, the Court found passengers in a vehicle have no reasonable expectation of privacy in the interior area of the car. Additionally, the Court in Wyoming v. Houghton held police officers with probable cause can inspect a passenger’s belongings.

According to Arizona v. Johnson, officers with probable cause can conduct a pat down (Terry stop) for weapons on both the driver and any passengers if they reasonably suspect they are armed. Per Michigan v. Long, police can also conduct a Terry protective search of the passenger compartment that could conceal a weapon and seize contraband in plain view.

The scope of the automobile exception extending to passengers and containers has changed over several rulings. In Arkansas v. Sanders, absent an exigent circumstance, the Court found it unreasonable to search one’s personal luggage without a warrant merely because it is in a vehicle.

The Court has ruled that once police officers have seized a suitcase from a vehicle, the risk of evidence loss is mitigated. Therefore, officers are required to obtain a warrant to conduct a search of the private property.

However, the Court overturned this ruling in California v. Acevedo, finding that police officers can search a particular container in a motor vehicle if probable cause exists to believe it contains contraband. But probable cause for one particular object of the search, such as a package in a trunk, does not necessarily extend to a search of the entire motor vehicle.

Given these rulings, It is often confusing for passengers to know when they can assert their rights to challenge unlawful searches or seizures. So, in Brendlin v. California, the Court found when law enforcement officers conduct a traffic stop, passengers like the driver are also seized. So, this provides standing for passengers to challenge the constitutionality of the stop under the Fourth Amendment.

The Bounds of Police Authority in Vehicle Searches

Given the nuances of the automobile exception, you may wonder how all these rules are practically applied. The following is a list of examples you may run into on a daily basis.

Can a police officer remove items obscuring their view of your VIN number?

Yes. In New York v. Class, the Court found no reasonable privacy interest in a vehicle identification number (VIN). A state law required a specific placement of the VIN. In this case, the defendant had items that obscured the view of the VIN, so an officer moved these items and observed a gun. The Court found the search did not violate the defendant’s Fourth Amendment rights.

Can police officers delay a traffic stop to conduct a canine search?

No. According to Illinois v. Caballes, officers cannot prolong a traffic stop beyond the time necessary to process a routine traffic violation in order to conduct a canine sniff.

Does consent to search a vehicle extend to containers?

Yes. In Florida v. Jimeno the Court found the defendant validly waived his Fourth Amendment protections when he consented to a search of his vehicle. After obtaining permission, Police opened a container and found cocaine.

Real-World Implications of Supreme Court Rulings

The expansion of the automobile exception allows police to search vehicles, passengers, and containers where there is probable cause. This does not take away your right to challenge the validity of the traffic stop. Additionally, remember the police must have articulable facts to suspect criminal activity, not merely a guess or hunch. Probable cause does not provide a blanket exception to conduct warrantless searches.

Court decisions shape law enforcement practices. So, the debate over privacy rights versus law enforcement's need to maintain public safety will continue. With fast-developing technology, such as self-driving cars, the Court will have to continue reviewing the automobile exception.