N.Y. Real Prop. Acts. Law § 305

§ 305. Compelling witnesses to testify. On the application of a\ngrantee in a conveyance, his heir or personal representative, or a\nperson claiming under either of them, verified by the oath of the\napplicant, stating that a witness to the conveyance, residing in the\ncounty where the application is made, refuses to appear and testify\nconcerning its execution, and that such conveyance can not be proved\nwithout his testimony, any officer authorized to take, within the state,\nacknowledgment or proof of conveyance of real property may issue a\nsubpoena, requiring such witness to attend and testify before him\nconcerning the execution of the conveyance. A subpoena issued under this\nsection shall be regulated by the civil practice law and rules.\n