Section 499 - Defenses to charges of perjury(1) Upon accusation of a charge of perjury by single statement, as defined in Section 491 of Title 21, it is a defense that the statement is true.(2) Upon accusation of a charge of perjury by contradictory statements, as defined in Section 496 of Title 21, it is a defense that the accused at the time he made each statement believed the statement was true.Okla. Stat. tit. 21, § 499