Modern Perjury Statutes
Each of the fifty states has its own perjury statute, and federal law contains two general perjury provisions (18 U.S.C. §§ 1621, 1623). Although differences abound among these statutes, most modern perjury statutes have four elements: (1) the statement must be made under oath; (2) the statement must be false; (3) the speaker must intend to make a false statement; and (4) the statement must be material to the proceeding. Each element must be proven by the prosecution beyond a reasonable doubt.
Oath. The oath may take many different forms, so long as it contains a solemn declaration to tell the truth. It must, however, be administered by a person legally authorized to do so and in a setting in which the oath is authorized to be administered. The oath can apply both to oral testimony and to written declarations made under the penalties of perjury.
Falsity. To be perjurious, a statement made under oath must be false. Thus, a perjury conviction cannot be based upon a statement that is so vague or ambiguous that it cannot be considered affirmatively false. Similarly, as the Supreme Court held in Bronston v. United States, (409 U.S. 352 (1973)), a statement that is misleading, but not actually false, cannot lead to a perjury conviction. In that case, the defendant Bronston had testified under oath in a bankruptcy hearing, during which he was asked whether he had ever had any Swiss bank accounts. Bronston responded that his company had once had a Swiss bank account. Although Bronston's response was literally true, it was misleading because it suggested that Bronston had not had a personal Swiss bank account, which he had. The Supreme Court nevertheless held that Bronston could not be prosecuted for perjury because his answer, even if deliberately deceptive, was not actually false. While the Court did not condone Bronston's misleading testimony, it reasoned that it was the questioner's responsibility to ensure that Bronston's answers were not ambiguous or non-responsive.
Intent. To be guilty of perjury, a defendant must do more than make a false statement under oath. The defendant must also intend to do so. Sometimes referred to as "scienter," this intent requirement is expressed in various ways. The federal perjury statutes require the false statement to be made "willfully" or "knowingly." Other state statutes require the statement to be made with an intent to mislead or with a belief that the statement was untrue. The intent requirement means that an "honest mistake" or an unknowing falsehood cannot be perjurious.
Materiality. The final element of most perjury statutes is the requirement that the false statement be "material" to the proceeding in which it is made. To be material, a statement must have the tendency or capacity to influence the court or other body before which the statement is made. Materiality is a broad concept, and a statement will be considered material not only if it directly relates to the matters at issue in the proceeding, but also if it could lead to the discovery of other relevant evidence or if it could enhance (or detract from) the credibility of a witness.
Materiality was traditionally considered to be an issue of law to be decided by the judge presiding over a perjury prosecution. In 1995, however, in addressing the related crime of making an unsworn false statement, the Supreme Court ruled that the materiality of a false statement was an issue for the jury. Shortly thereafter, the Supreme Court applied the same reasoning to the materiality element in perjury prosecutions. Thus, as with the other elements of the crime, the materiality element in a perjury case must be proven by the prosecution to the jury beyond a reasonable doubt.