Answer: libeler

AnswerCrossword Clue
LIBELERMaligner of a sort
LIBELEROne who writes damaging lies about a person
LIBELERCandidate for a suit
LIBELEROne who defames
libelerperson who libels; person who publishes a libel assailing another
libelerone that libels, also LIBELIST, LIBELLER