Which case established the concept of the 'Terry stop' involving stop and frisk?

The landmark case that established the concept of the 'Terry stop' is Terry v. Ohio. In this 1968 decision, the Supreme Court held that police officers are permitted to stop and briefly detain a person for questioning if they have a reasonable suspicion that the person is involved in criminal activity. This case arose from a situation where an officer observed two men engaging in what he believed to be a drug transaction.

The significance of the ruling lies in the balance it strikes between the needs of law enforcement to protect themselves and prevent crime, and the Fourth Amendment rights of individuals against unreasonable searches and seizures. The Court concluded that if an officer reasonably suspects that a person may be armed and dangerous, they can conduct a limited frisk for weapons, even if there's no probable cause to make an arrest. This precedent allows law enforcement to take necessary precautions while ensuring constitutional protections for citizens.

Cases like Michigan Department of State Police v. Sitz, Mapp v. Ohio, and Illinois v. Gates address different aspects of law enforcement and constitutional rights, but they do not pertain to the specific parameters established for 'stop and frisk' procedures as defined in Terry v. Ohio.