Encounter
(No Basis for "Seizure")

4th Amendment Seizure
(4th Amendment "Seizure" of a "Free Person")

DON'T - STOP
DON'T - DEMAND
DON'T - USE FORCE

DO - ASK TO TALK
DO - ASK FOR ID
DO - ASK FOR EXPLANATION

Detention/Frisk
Terry v. Ohio, 392 U.S. 21, 88 S.Ct. 1868 (1968)
"Reasonable Articulable Suspicion"

Arrest
"Probable Cause"

Detention
"Reasonable Articulable Suspicion"

To believe that:
(1) a crime has been committed
(2) a crime is being committed, or
(3) a crime is about to be committed; AND
(4) the person about to be stopped is the person who did one of the above.

The Procedure:

(1) After identifying as a police officer
(2) an officer may stop a person:
_(a) in a public place
_(b) for a reasonable ____period of time
_(c) when the officer ____reasonably ____suspects that such ____person is ____committing, is about ____to commit, or has ____committed a crime.
(3) Such detention and temporary questioning shall be conducted in the vicinity where the person was stopped

(1) The officer reasonably believes
(2) that the lawfully detained person
(3) is armed and/or dangerous or that the officer or another is in danger of physical injury
(4) the officer may search such person for weapons or any instrument, article or substance readily capable of causing physical injury and of a sort not ordinarily carried in public places by law abiding persons.
(5) If the officer finds such a weapon or instrument, or any other property possession of which he reasonably believes may constitute the commission of a crime, or which may constitute a threat to his safety,
(6) the officer may take it and keep it until the completion of the questioning;
(7) at which time he shall either return it, if lawfully possessed, or arrest the person so questioned

Probable Cause - a "fair probability" that a crime has been committed and the person being seized committed it