In 1968 the United States Supreme Court decided the case Terry v. Ohio, 392 U.S. 1. From that case is what came to be known as the Terry Stop Exception to the Fourth Amendment. This exception permits a policeman who lacks probable cause but whose observations lead him reasonably to suspect that someone is committing a crime, or just committed a crime, or is just about to commit a crime, to detain the suspect and investigate him.
The policeman’s investigation must be connected with the original reason for stopping the suspect and the investigation must be limited. The inquiry may include asking the detained individual a moderate number of questions to determine his identity and to obtain information in support of the officer’s suspicions. What people should keep in mind is that even if a cop conducts a Terry stop, the detained individual does not have to answer the cop’s questions. If the officer asks for identification then the suspect has to give him that, but he does not have to answer any questions. The risk a detainee runs by answering questions if that the officer will develop probable cause from the detainee’s answers, thereby allowing the officer to arrest him. If the detainee simply says nothing, the cop has to let him go.
A Terry stop, however, does not oblige the officer to give Miranda warnings to the detained individual, so anything that a suspect says during a Terry stop can be used against him.
The most common example of a Terry stop is a traffic stop. Police officers patrolling the streets for would-be criminals are permitted under the law to stop any vehicle that gives a policeman “reasonable suspicion” that the vehicle’s occupants committed a crime. This standard is satisfied by the breaking of a basic traffic law such as speeding or not coming to a complete stop. When one breaks a traffic law he has committed a crime, and therefore, the policeman who witnesses this has “reasonable suspicion” to stop the vehicle.
Once the cop conducts the Terry stop he may conduct a brief frisk of the person if the officer “reasonably feared for his safety or the safety of others.” Under the Terry frisk exception the cop can conduct a warrantless search of the person if the circumstances are such that a substantial risk of harm could result to the persons involved if the search were delayed in order to get a warrant. Officers must still be able to point to specific and articulable facts which would lead a reasonable person to conclude that the suspect may be armed and dangerous.
The Terry stop and frisk exception is a terrible law and gives law enforcement way too much power to harass people. At least they can’t force us to talk…yet.