Miss. Code § 21-29-101
Except as otherwise provided in this section, in every city of the State of Mississippi having a population of ten thousand (10,000) or more, according to the last federal census, or any subsequent federal census, and in which there is a paid police department and/or fire department, it shall be the duty of the governing authorities of said municipality to create and maintain a fund known as the "disability and relief fund for firemen and policemen," hereafter to be known as "said fund," which shall be maintained for the benefit of the persons hereinafter named, and shall be derived, raised and administered in the manner provided in this article, except no such fund known as the "disability and relief fund for firemen and policemen" shall be created by any municipality after March 1, 1976, unless approved by an amendment to this article by the Legislature of the State of Mississippi. Further, no new members may be joined by the fund after July 1, 1987, and all new employees of the police department and/or fire department of any municipality having such funds shall become members of the Public Employees' Retirement System of Mississippi after July 1, 1987.
Any reference in other sections of this article to members of the fire or police department shall be defined to include only the members of the disability and relief fund for firemen and policemen of the municipality. The fund for each municipality shall be separately administered.
This section and Sections 21-29-103 through 21-29-151 shall not apply to any municipality wherein the qualified electors of such municipality shall have elected on or before August 6, 1940, pursuant to the then applicable law, not to have such municipality come within the provisions of Sections 21-29-101 to 21-29-151.
Miss. Code § 21-29-101