735 ILCS 5/1-104

(a) The Supreme Court of this State has power to make rules of pleading, practice and procedure for the circuit, Appellate and Supreme Courts supplementary to, but not inconsistent with the provisions of this Act, and to amend the same, for the purpose of making this Act effective for the convenient administration of justice, and otherwise simplifying judicial procedure, and power to make rules governing pleading, practice and procedure in small claims actions, including service of process in connection therewith. Unless otherwise indicated by the text, references in this Act to rules are to rules of the Supreme Court. (b) Subject to the rules of the Supreme Court, the circuit and Appellate Courts may make rules regulating their dockets, calendars, and business.