La. Stat. tit. 49 § 852
Because of the possibility of attack of unprecedented size and destructiveness upon the United States, to assure continuity of government through legally constituted leadership, authority and responsibility in offices of the government of the state, in the event of such an attack, to provide for the effective operation of government during an emergency and to facilitate the early resumption of functions temporarily suspended, it is found and declared to be necessary to provide for emergency interim succession to state governmental offices, except that of Governor, in the event that the incumbents thereof and their deputies, assistants or other subordinate officers authorized, pursuant to law, to exercise all of the powers and discharge the duties of such offices, hereinafter referred to as deputies, are unavailable to perform the duties and functions of such offices.
La. R.S. § 49:852