So here again I see a familiar syndrome on Cold Filter: Some people wondering aloud, while others state authoritative facts--which may not be authoritative at all. Surely it's easier to do a quick search before posting?
For the benefit of George:
Criminal libel does exist although it is seldom used.
As for libel generally, there are many good educational sources online. My own education in libel was gained most productively by watching a friend of mine go through a four-week trial which was the culmination of a libel law suit that had dragged on for SIX YEARS. He won the suit, but of course he could never regain the lost time.