Ill. Const. art. XII, § 4. COMMANDER-IN-CHIEF AND OFFICERS

(a) The Governor is commander-in-chief of the organized militia, except when they are in the service of the United States. He may call them out to enforce the laws, suppress insurrection or repel invasion. (b) The Governor shall commission militia officers who shall hold their commissions for such time as may be provided by law. (Source: Illinois Constitution.)