La. C.C.P. art. 1005. — Affirmative defenses

The answer shall set forth affirmatively negligence, or fault of the plaintiff and others, duress, error or mistake, estoppel, extinguishment of the obligation in any manner, failure of consideration, fraud, illegality, injury by fellow servant, and any other matter constituting an affirmative defense. If a party has mistakenly designated an affirmative defense as a peremptory exception or as an incidental demand, or a peremptory exception as an affirmative defense, and if justice so requires, the court, on such terms as it may prescribe, shall treat the pleading as if there had been a proper designation.