? 4902. Perjury.
(a) Offense defined.--A person is guilty of perjury, a
felony of the third degree, if in any official proceeding he
makes a false statement under oath or equivalent affirmation, or
swears or affirms the truth of a statement previously made, when
the statement is material and he does not believe it to be true.
(b) Materiality.--Falsification is material, regardless of
the admissibility of the statement under rules of evidence, if
it could have affected the course or outcome of the proceeding.
It is no defense that the declarant mistakenly believed the
falsification to be immaterial. Whether a falsification is
material in a given factual situation is a question of law.
(c) Irregularities no defense.--It is not a defense to
prosecution under this section that the oath or affirmation was
administered or taken in an irregular manner or that the
declarant was not competent to make the statement. A document
purporting to be made upon oath or affirmation at any time when
the actor presents it as being so verified shall be deemed to
have been duly sworn or affirmed.
(d) Retraction.--No person shall be guilty of an offense
under this section if he retracted the falsification in the
course of the proceeding in which it was made before it became
manifest that the falsification was or would be exposed and
before the falsification substantially affected the proceeding.
(e) Inconsistent statements.--Where the defendant made
inconsistent statements under oath or equivalent affirmation,
both having been made within the period of the statute of
limitations, the prosecution may proceed by setting forth the
inconsistent statements in a single count alleging in the
alternative that one or the other was false and not believed by
the defendant. In such case it shall not be necessary for the
prosecution to prove which statement was false but only that one
or the other was false and not believed by the defendant to be
true.
(f) Corroboration.--In any prosecution under this section,
except under subsection (e) of this section, falsity of a
statement may not be established by the uncorroborated testimony
of a single witness.