WordNet (r) 3.0 (2006):

false witness
    n 1: a person who deliberately gives false testimony [syn:
         perjurer, false witness]

Moby Thesaurus II by Grady Ward, 1.0:

29 Moby Thesaurus words for "false witness":
   Ananias, Baron Munchausen, Father of Lies, Satan,
   Sir John Mandeville, consummate liar, dirty liar, equivocator,
   fabricator, fabulist, falsifier, fibber, fibster, frame, frame-up,
   habitual liar, liar, mythomaniac, palterer, pathological liar,
   perjurer, prevaricator, pseudologist, pseudologue, put-up job,
   spinner of yarns, storyteller, yarn spinner, yarner