Deuteronomy 19:16-21

16If a false witness rise up against any man to testify against him that which is wrong;1 17Then both the men, between whom the controversy is, shall stand before Yhwh, before the priests and the judges, which shall be in those days; 18And the judges shall make diligent inquisition: and, behold, if the witness be a false witness, and hath testified falsely against his brother; 19Then shall ye do unto him, as he had thought to have done unto his brother: so shalt thou put the evil away from among you. 20And those which remain shall hear, and fear, and shall henceforth commit no more any such evil among you. 21And thine eye shall not pity; but life shall go for life, eye for eye, tooth for tooth, hand for hand, foot for foot.