When Texas motorists are pulled over by law enforcement, the Fourth Amendment protects them against unreasonable searches and seizures. This means that police officers cannot search their vehicles unless they have sound reasons. When the actions of police officers are questioned, the arguments usually boil down to whether or not their behavior was reasonable. The courts take the Fourth Amendment very seriously, but they have created exceptions that allow police officers to conduct warrantless searches in some situations.
When warrantless searches are legal
It has long been established that police officers may search suspects and their vehicles incident to an arrest. Police officers are also allowed to conduct warrantless searches when they are given consent or have probable cause to believe that a crime has been committed, is being committed or will be committed. When a police officer asks for consent to conduct a search, it suggests that they do not have probable cause to act without a warrant. Police officers may also seize evidence of criminal activity that they observe in plain sight, and the courts have ruled that a police dog alerting to the presence of drugs or firearms while sniffing the air around a vehicle meets the requirements of the plain sight doctrine.
Terry stops
The U.S. Supreme Court created another exemption to Fourth Amendment protections after hearing arguments in the 1968 case Terry v. Ohio. The case involved a man who was arrested after police officers patted him down and found a gun. The justices ruled that police officers are permitted to pat down suspects they have reason to believe are armed to protect themselves and others. This is why prosecutors and criminal defense attorneys refer to weapons pat downs as Terry stops.
Robust protection
The Fourth Amendment provides robust protections against unreasonable government searches and seizures, but police officers are permitted to conduct warrantless searches in certain situations. Police officers can search suspects or their vehicles when they see evidence of criminal activity in plain sight, are given consent or have probable cause to believe that a crime is being committed, will be committed or has been committed. Police officers are also permitted to pat down suspects that they believe are armed.