The Fourth Amendment to the U.S. Constitution gives citizens the right to be free from unreasonable searches and seizures. Under the Fourth Amendment to the US Constitution, the police are prohibited from conducting a search and seizure without "probable cause."According to the Fourth Amendment, searches can not be conducted without a warrant. That's why the Fourth Amendment protects "persons" from unreasonable searches and seizures. Vehicles may be searched without warrants if the officer undertaking the search has probable cause to believe that the vehicle contains contraband. —In the early days of the automobile, the Court created an exception for searches of vehicles, holding in Carroll v. Under the Fourth Amendment, searches and seizures without a warrant are presumptively unreasonable subject only to specified exceptions. He orders you out of the car. Maybe he wants to place you under arrest. Eas enumerated in the Fourth Amendment itself. See.