N.Y. County Law § 920

§ 920. Alphabetical indices in offices of county clerks. The clerk of\neach of the counties within the city of New York, so long as he deems it\nexpedient, may continue the alphabetical indices of the parties to\nnotices of lis pendens, statutory notice of liens and claims upon land,\nor of the parties to either of them, and of the owners of land against\nwhich liens have been filed and of judgment debtors whose names appear\non record. The particular form of such alphabetical indices shall be as\nsuch county clerk shall determine, and shall be certified by him as\nhaving been prepared under the authority of this article. Such indices\nshall be kept in the office of the county clerk or in such other place\nas shall be provided for them and shall be public records.\n