Miranda v. Arizona, 384 U.S. 436 (1966)-The Miranda case is a very important case to law enforcement. The United States Supreme Court established an irrebuttable presumption that a statement is involuntary if made during a custodial interrogation without the "Miranda Warnings" given. The warning requirements only apply when a person is in custody and interrogated. In this case, "custody" is an arrest or when freedom   is significantly deprived to be equivalent to an arrest. "Interrogation" is the use of words or actions to elicit an incriminating response from an average person.

Terry v. Ohio, 392 US 1(1968)-An officer can briefly detain a person, based upon reasonable suspicion of criminal activity, long enough to dispel the suspicion or to allow it to rise to the level of probable cause for an arrest. The officer is also permitted to do a limited "frisk" search of the person without a warrant. Before the officer can frisk search the subject, he must:

The case further dictates that the arrest must be reasonably proportionate to the need of force as measured by:

Before deploying a flash-bang, the officer needs to: