William Safire a Pulitzer prize winning columnist with the NY Times got it right in 1996 (20 years ago) when he called Hillary Clinton a 'congenital liar'.
Definition:
con·gen·i·tal
ADJECTIVE
(of a person) having a particular trait from birth or by firmly established habit: "a congenital liar" synonyms: inveterate · compulsive · persistent · chronic ·