(1) A person is guilty of perjury in the first degree if in any official proceeding he or she makes a materially false statement which he or she knows to be false under an oath required or authorized by law.

(2) Knowledge of the materiality of the statement is not an element of this crime, and the actor's mistaken belief that his or her statement was not material is not a defense to a prosecution under this section.

(3) Perjury in the first degree is a class B felony.