...you shall not bear false witness against your fellow. (Exodus 20:13)
Deuteronomy 19:15-21 A single witness shall not stand up against any man for any iniquity or for any error, regarding any sin that he may commit; according to two witnesses or according to three witnesses shall a matter be confirmed. If a false witness stands against a man to speak up spuriously against him, then two men [and those] who have the grievance shall stand before Hashem, before the Kohanim and the judges who will be in those days. The judges shall inquire thoroughly, and behold! the testimony was false testimony; he testified falsely against his fellow. You shall do to him as he conspired to do to his fellow, and you shall destroy the evil from your midst. And those who remain shall hearken and fear; and they shall not continue again to do such an evil thing in your midst. Your eye shall not pity; life for life, eye for eye, tooth for tooth, hand for hand, foot for foot.
A person who bears false witness and thus frames his fellow for a crime he had not committed, is committing a grave crime and will be punished according to his sin--he will receive his own judgement, for he had sought to condemn an innocent person, and will be guilty for this sin. But if one should spread a false rumor, without testifying in court, thus shaming his fellow before his people and ruining his name; this is like stealing his fellow's identity, and goes against the Eighth Commandment. For shaming a person this way, the one who spreads the rumors must clear the name of his fellow and return his honor to him--the honor of his name and of his household. Thus the one who spreads the rumors will be shamed, and his name will be cursed for having sinned this way.
However, such a matter might be tried. If, when it is tried by judges, the sinner bears false witness against his fellow in order to deny his sin, then he will suffer accordingly, for "You shall do to him as he conspired to do to his fellow, and you shall destroy the evil from your midst."