N.Y. Penal Law § 210.25

§ 210.25 Perjury; defense.\n In any prosecution for perjury, it is an affirmative defense that the\ndefendant retracted his false statement in the course of the proceeding\nin which it was made before such false statement substantially affected\nthe proceeding and before it became manifest that its falsity was or\nwould be exposed.\n