Deuteronomy 19:15-20 King James Version (KJV)
15 One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.
16 If a false witness rise up against any man to testify against him that which is wrong;
17 Then both the men, between whom the controversy is, shall stand before the Lord, before the priests and the judges, which shall be in those days;
18 And the judges shall make diligent inquisition: and, behold, if the witness be a false witness, and hath testified falsely against his brother;
19 Then 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.
20 And those which remain shall hear, and fear, and shall henceforth commit no more any such evil among you.