La. Civ. Code art. 1626
Current with operative changes from the 2024 Third Special Legislative Session
A disinherison shall not be effective if the person who is disinherited shows that because of his age or mental capacity he was not capable of understanding the impropriety of his behavior or if he shows that the behavior was unintentional or justified under the circumstances. Proof of this defense must be by a preponderance of the evidence, but the unsupported testimony of the disinherited heir shall not be sufficient to establish this defense.
La. C.C. § 1626