20 ILCS 1805/94
It is unlawful for any body of men or women, other than the regularly organized militia of this State, troops of the United States, Grand Army posts, camps of the Sons of Veterans or organizations of veterans of the Spanish-American War, Philippine Insurrection, World War I, World War II, or any future wars, dedicated to the welfare of the State and nation, to associate themselves together as a military company or organization, to drill or parade with arms in this State, except as hereinafter authorized; but, by and with the consent of the Governor, independent regiments, battalions or companies, organized for the purpose of recreation or to acquire military knowledge that may better enable them to serve the State in time of public peril, if such should arise, may associate themselves together as a military body or organization and may drill or parade with arms in public in this State, and students of educational institutions, where military drill is a part of the course of instructions, may, with the consent of the Governor, drill and parade with arms in public under command of their military instructors. Nothing herein contained shall be construed so as to prevent benevolent or social organizations from wearing swords. All military organizations in and by this Section permitted to drill and parade with arms, shall, on occasions of public parade, be required to carry the United States flag in addition to any private ensign which they may carry. The consent herein specified may be withdrawn at the pleasure of the Governor.
20 ILCS 1805/94