Deuteronomy 19:16-19

16If a false witness testifies against someone, accusing him of a crime, 17both parties to the dispute must stand in the presence of the LORD, before the priests and judges who are in office at that time. 18The judges shall investigate thoroughly, and if the witness is proven to be a liar who has falsely accused his brother, 19you must do to him as he intended to do to his brother. So you must purge the evil from among you.1