N.Y. CPL Law § 450.50

§ 450.50 Appeal by people from order suppressing evidence; filing of\n statement in appellate court.\n 1. In taking an appeal, pursuant to subdivision eight of section\n450.20, to an intermediate appellate court from an order of a criminal\ncourt suppressing evidence, the people must file, in addition to a\nnotice of appeal or, as the case may be, an affidavit of errors, a\nstatement asserting that the deprivation of the use of the evidence\nordered suppressed has rendered the sum of the proof available to the\npeople with respect to a criminal charge which has been filed in the\ncourt either (a) insufficient as a matter of law, or (b) so weak in its\nentirety that any reasonable possibility of prosecuting such charge to a\nconviction has been effectively destroyed.\n 2. The taking of an appeal by the people, pursuant to subdivision\neight of section 450.20, from an order suppressing evidence constitutes\na bar to the prosecution of the accusatory instrument involving the\nevidence ordered suppressed, unless and until such suppression order is\nreversed upon appeal and vacated.\n