La. Stat. tit. 13 § 5129
In the event the decree of the court validates the bonds or validates the action taken to provide a new or different source of payment for the bonds, and no appeal is taken within the time above prescribed, or if appeal is taken and the decree of the court is affirmed, such decree shall be forever binding and conclusive as to the validity of the bonds, the validity of the tax, any lease or other means provided for the payment of such bonds and the validity of all pledges of revenues and of all covenants and provisions contained in the instrument or proceedings authorizing or providing for the issuance of such bonds, and as to all matters adjudicated and as to all objections presented or which might have been presented in such proceeding, and shall constitute a permanent injunction against the institution by any person of any action or proceeding contesting the validity of the bonds or any other matter adjudicated or which might have been called in question in such proceedings.
La. R.S. § 13:5129