La. Code Evid. art. 519

A. General rule. Neither a subpoena nor a court order shall be issued to a judge or his representative to appear or testify in any civil, criminal, or juvenile proceeding, including pretrial discovery or an administrative hearing, unless, after a contradictory hearing, it has been determined that the information sought is not protected from disclosure by the judicial deliberative process privilege, and all of the following:

(1) The information sought is essential to the case of the party seeking the information and is not merely peripheral, cumulative, or speculative.

(2) The purpose of seeking the information is not to harass the judge, nor for the mere purpose of seeking recusal of the judge.

(3) With respect to a subpoena, the subpoena lists the information sought with particularity, is reasonably limited as to subject matter and period of time, and gives timely notice.

(4) There is no practical alternative means of obtaining the information.

B. Waiver. Failure to object timely to a party's non-compliance with the provisions of this Article constitutes a waiver of the procedural protections of this Article, but does not constitute a waiver of any privilege.

C. The procedural provisions of and the protections afforded by Paragraph A of this Article shall extend to any judge of any court provided for by Article V of the Constitution of Louisiana and to any commissioner or special master of such court.