As we previously reported, the "American Idol" champ had been in a relationship with a man named Antwaun Cook -- who is still married to Paula Cook. Paula recently filed for divorce ... and in the legal papers, cited an "adulterous affair" between Fantasia and Antwaun.
Cook has not taken any legal action against Fantasia yet -- but Barrino's lawyer, Gena Graham Morris, tells us it very well COULD happen ... because in NC there are certain "heartbalm torts ... where a wife can sue a third party for having a relationship with her husband" -- it's called alienation of affection.
Morris adds, "The heartbalm torts arise out of the notion that women were once property that could be stolen like televisions. It is a comical irony that in 2010 women can sue women for stealing husbands."
Morris says she "hopes" Paula Cook will choose not to sue -- but in case she does, Morris vows to "vigorously defend" Fantasia.