N.Y. PEN. LAW § 245.00 : NY Code - Section 245.00: Public lewdness

A  person  is  guilty of public lewdness when he intentionally exposes
  the private or intimate parts of his body in a lewd  manner  or  commits
  any  other  lewd  act  (a) in a public place, or (b) in private premises
  under circumstances in which he may readily be observed  from  either  a
  public  place or from other private premises, and with intent that he be
  so observed.
    Public lewdness is a class B misdemeanor.