La. Public Health and Safety § 40:1570
The fire marshal or his authorized representative may, at all times of day or night, in the performance of the duties imposed by the provisions of this Part, enter upon and examine any building or premises where any fire has occurred and other buildings or premises adjoining or near thereto. He, or his authorized representative, may make an affidavit before any justice of the peace in the state or any other officer authorized by law to issue search warrants that he believes or has reason to believe that by a search of certain premises, designated in the affidavit, he will obtain evidence tending to show the origin of a fire to have been incendiary. Upon receiving this affidavit, the justice of the peace, or other officer shall issue a warrant authorizing the fire marshal or his representative to search the premises named in the affidavit and designated in the warrant.
La. Public Health and Safety § 40:1570