Perjury is the criminal offense of making a false statement under oath—verbally or in writing—that the witness knows to be false and that is material to the proceeding in which the statement is made. And suborning perjury or subornation of perjury is the criminal offense of procuring the perjury of another person.

Perjury is a criminal offense under both state and federal laws and may be prosecuted as a misdemeanor or as a felony offense, depending on the state or federal jurisdiction, and whether there are any aggravating factors that increase the seriousness of the crime. Perjury laws are located in state statutes—often in the penal or criminal code—and the federal perjury law is located in the United States Code at 18 U.S.C. §1621.

In California, perjury is defined as the willful act of providing false information while under oath, whether orally or in writing, on matters significant to a legal proceeding. It is considered a felony under California Penal Code Section 118. The law requires that the individual knew the statement was false at the time it was made and that the statement was made with the intent to deceive. A conviction for perjury under California law can result in up to four years of imprisonment. Subornation of perjury, which involves persuading or inducing another person to commit perjury, is also a felony in California and is covered under California Penal Code Section 127. Like perjury, subornation of perjury can lead to severe penalties including prison time. These state laws operate alongside federal law, which criminalizes perjury under 18 U.S.C. § 1621, and subornation of perjury under 18 U.S.C. § 1622, with both offenses potentially leading to fines and imprisonment if convicted at the federal level.