The Fourth Amendment's Application to Vehicle Searches

National Police Training
June 20, 2012 — 1,746 views  
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The Fourth Amendment is a vital part of the United States Constitution. This amendment is one of 10 that make up the Bill of Rights, all of which guarantee the basic freedoms of U.S. citizens. Specifically, this clause protects against unreasonable searches and seizures, and requires law enforcement officials to obtain explicit warrants when they request to search personal property. When it comes to a motor vehicle search, police should know citizen's Fourth Amendment Rights.

Though a motor vehicle is considered personal property like a home or apartment, there is an exception to the warrant rule. The U.S. Supreme Court first established this precedent in the 1925 case of Carroll versus the United States. Due to Prohibition, federal agents purchased illegal liquor during an undercover sting operation from bootlegger George Carroll. They pulled his automobile over and searched it without a warrant, and found the illegal alcohol underneath the back seat. The National Prohibition Act allowed them to legally search the vehicle if they had probable cause, and in this case, the belief of the presence of illegal goods was enough.

As a result, modern-day law enforcement officials are allowed to search a vehicle without a search warrant if there is probable cause. However, there are a few restrictions to this legal exemption.

For example, the scope of an officer's search is limited to the area extended underneath probable cause. Therefore, if thumping noises are heard from the trunk, an officer can investigate the disturbance, but not the glove compartment. At the same time, if the car is filled with marijuana smoke, the officer might be able to search the entire car due to the actual presence of illegal drugs.

In addition, some state constitutions have explicit requirements for the responding officer to document that there was not enough time to obtain a search warrant. Essentially, law enforcement personnel must demonstrate that the emergency situation forced their hand. This would be applicable if the suspect had already tried to run away from the police, or had initiated a car chase.

Probable cause is not limited to motor vehicles, however - motor homes, parked mobile properties and other wheeled units are subject to the same Fourth Amendment exemptions.

Police officers should be aware that these particular searches may fall underneath the category of a home, and therefore owner permission may still be required. If a homeowner refuses a search, it may be prudent to radio it in and try to obtain a house warrant.

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