In the law of the United States, reasonable suspicion is a standard which must be met for a law enforcement officer to conduct a stop and frisk. Other nations may have similar standards, depending on how their legal systems are structured. It is important for people from the United States to be aware that the reasonable suspicion standard is not present in all nations and that law enforcement can behave very differently during routine stops in some regions of the world.
This standard is based on the mythical “reasonable person.” If reasonable suspicion is met, it means that a reasonable person would have had reason to believe that the person in question was either about to commit a crime, or had committed a crime. This standard is not as high as probable cause, the standard which must be met to issue a warrant.
Some examples of situations in which reasonable suspicion could be met include a situation in which a crime has just been committed and someone matching the description of the culprit is spotted by police, someone in the area of a crime who flees or avoids police contact, someone who drops a suspicious item in the presence of a police officer, or someone carrying tools and equipment which might be used to commit a crime. For example, someone strolling down the street with a baseball bat at three in the morning and eyeing the contents of cars could meet the standard for reasonable suspicion.
If an officer has a reasonable suspicion that someone is involved in criminal activity, that person can be stopped and frisked for weapons in a procedure known as a Terry stop. If the police officer thinks that the person may be armed, the person can be stopped at gunpoint to protect the officer's safety. The target of the reasonable suspicion can also be briefly detained while the police officer asks some questions.
It is important to note that if a police officer stops someone and starts asking questions, refusal to answer questions is not grounds for reasonable suspicion. Neither is asking if one is free to go. When someone is stopped by police in the United States, it is entirely appropriate to ask if one is free to go, and if the officer replies “no,” the person who has been stopped can indicate that he or she will not answer any further questions without a lawyer present.