The Oregonian has an article by Edward Walsh that discusses the amount of perjury that regularly occurs in courts. In the federal system perjury is controlled by 18 U.S.C. s 1621 which requires that the "government prove that the defendant 1) under oath, by one authorized to administer the oath; 2) before a competent tribunal, officer, or person; 3) made a false; 4) material statement; 5) willfully and with knowledge of its falsity." See White Collar Crime in a Nutshell.

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