N.Y. DOM Law § 171

§ 171. When divorce denied, although adultery proved. In either of the\nfollowing cases, the plaintiff is not entitled to a divorce, although\nthe adultery is established:\n 1. Where the offense was committed by the procurement or with the\nconnivance of the plaintiff.\n 2. Where the offense charged has been forgiven by the plaintiff. The\nforgiveness may be proven, either affirmatively, or by the voluntary\ncohabitation of the parties with the knowledge of the fact.\n 3. Where there has been no express forgiveness, and no voluntary\ncohabitation of the parties, but the action was not commenced within\nfive years after the discovery by the plaintiff of the offense charged.\n 4. Where the plaintiff has also been guilty of adultery under such\ncircumstances that the defendant would have been entitled, if innocent,\nto a divorce.\n