Stop-and-frisk procedures when performed in a constitutional manner are fundamental to modern policing—officers continually apply stop-and-frisk principles during traffic stops, other short detentions of citizens, and limited searches. The legal concept of stop-and-frisk was established in the landmark case Terry v. Ohio, which authorized law enforcement to detain a person and conduct a limited search of the outer clothing for weapons where the officer has reasonable suspicion that “criminal activity may be afoot and that the persons… may be armed and presently dangerous” (known as a Terry stop). The U.S. Supreme Court has further explained that courts will consider the “totality of the circumstances” when assessing the validity of a Terry stop. The authority for police to stop-and-frisk citizens based on reasonable suspicion of criminal activity is a well-grounded and indisputable principle of constitutional law, and it is reasonable to assume that informed law enforcement agencies have department policies that explain how officers are to appropriately use stop-and-frisk tactics and define the limits of officer authority during these encounters.