8.135 Perjury-Testimony (18 U.S.C. Sec. 1621) refers to a federal crime that occurs when a person knowingly lies or makes a false statement while under oath in a federal court or other official proceeding. This criminal offense is defined in the United States Code, Section 1621, and is punishable by a maximum of five years in federal prison. There are two types of perjury-testimony: willful and material. Willful perjury-testimony occurs when a person knowingly makes a false statement in a federal court or other proceeding. Material perjury-testimony occurs when a person knowingly makes a false statement which is material to the outcome of the case or proceeding. Both types of perjury-testimony can result in a federal conviction and a maximum of five years in prison.