New York Consolidated Laws, Penal Law - PEN § 210.30 Perjury;  no defense

1. The defendant was not competent to make the false statement alleged;  or

2. The defendant mistakenly believed the false statement to be immaterial;  or

3. The oath was administered or taken in an irregular manner or that the authority or jurisdiction of the attesting officer who administered the oath was defective, if such defect was excusable under any statute or rule of law.