Mississippi Code Title 9. Courts § 9-3-11

The judge of the Supreme Court who has been for the longest time continuously a member of the court shall be chief justice; and, the two (2) judges of the supreme court who have served continuously for the next longest time shall be presiding justices. In case of the absence of the chief justice, the presiding justice who has been for the longest time continuously a member shall preside. In the event that two (2) or more judges of the Supreme Court shall have served as members of the Supreme Court for equal periods of time, then seniority shall be determined according to the length of time that such judges shall have been members of the Mississippi State Bar.