Ark. Code Ann. § 14-42-116

No city of the first class, city of the second class, or incorporated town, regardless of the form of government, shall hereafter establish any retirement benefit system or plan for members of the governing body of the city or town except cities of the first class, cities of the second class, or incorporated towns which had established such system or plan prior to July 3, 1989. However, all systems and plans in existence on July 3, 1989, may continue.