N.Y. Real Property Actions & Proceedings Law § 301

§ 301. Conveyance and record as evidence. 1. The certificate of the\nacknowledgment or of the proof of a conveyance, or the record, or the\ntranscript of the record, of such a conveyance, is not conclusive, and\nit may be rebutted, and the effect thereof may be contested, by a party\naffected thereby.\n 2. If it appears that the acknowledgment or proof was taken upon the\noath of an interested or incompetent witness, the conveyance, or the\nrecord or transcript of the record thereof, shall not be received in\nevidence until its execution is established by other competent proof,\nexcept in a case where the title to the land conveyed or affected by\nsuch conveyance or instrument has passed to a subsequent purchaser for a\nvaluable consideration.\n