Source: https://fiskelaw.org/2013/03/05/street-encounters-with-police-debour-and-beyond/
Timestamp: 2019-04-22 22:52:25+00:00

Document:
Street Encounters with Police: DeBour and Beyond | Andrew Fiske, Esq.
There are four basic levels of street encounters with police in New York. People v. DeBour, 40 N.Y.2d 210 (1976).
The first is known as a “Request for Information,” where an officer may ask you some basic questions regarding who you are, where you live, where you’re going, etc. In order to do this, the officer must have an objective credible reason for asking; for instance, a crime recently occurred in the vicinity and the officer is looking for clues.
The officer may not detain you or even ask to search you (or your belongings) at this level, and you are free to ignore the questions and even to flee , although doing so will likely arouse suspicion, where there may have been none to begin with.
So, if you know you’re innocent and you feel safe speaking with police, then go ahead and do so. If not, then politely decline to answer any questions and be on your way.
The next level is the “Common Law Right to Inquire,” where an officer must have a founded suspicion of criminal activity. This suspicion must be based on your conduct observed by the officer, or from reliable information obtained from a third party.
Again, an officer may not detain or search you at this level, but simply has the right to ask questions. You, in turn, have the constitutional right not to respond and you should definitely exercise that right and/or ask for a lawyer, especially if the officer’s suspicion of criminal activity was correct.
This level is known as a “Stop and Frisk” or a Terry Stop. Terry v. Ohio, 392 U.S. 1 (1968). At this level, an officer has the right to stop and detain you, if there is reasonable suspicion that you committed, are committing, or are about to commit a crime.
The officer may then search you for weapons, or any instrument that could cause injury and take away any such instrument until the completion of questioning. CPL § 140.50.
This level is basically a pre-cursor to an arrest. It’s the right of an officer to remove any dangerous weapon from a person prior to the arrest. However, if an officer stops and searches you on less than reasonable suspicion, then any physical evidence of the search may be suppressed. People v. Hollman, 79 N.Y.2d 181, 195 (1992).
Any arrest without a warrant must be based on reasonable cause (often referred to as probable cause) that a person has committed an offense.
An officer may arrest someone for a petty offense (a violation or traffic infraction) only if he has reasonable cause to believe the person committed the offense in his presence. CPL § 140.10(1)(a).
An officer may arrest a person for a crime (any misdemeanor or felony), if he has reasonable cause to believe the person committed the crime, whether in his presence or otherwise. CPL § 140.10(1)(b).
All these technical terms and levels of suspicion may be confusing to non-lawyers, and even some lawyers out there. However, the basic thing to remember for any type of police encounter is to use your common sense in conjunction with asserting your legal rights.
An officer has no authority to exceed the level of the encounter beyond the appropriate level of the evidence and information that he is relying on. Since you probably have no idea what information the officer is relying on, the best thing to do is to: remain calm and be polite but immediately decline to answer questions and ask for a lawyer the minute you feel you may be suspected of wrongdoing.

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