720 ILCS 5/30-1

(a) A person owing allegiance to this State commits treason when he or she knowingly: (1) levies war against this State; or (2) adheres to the enemies of this State, giving them aid or comfort. (b) No person may be convicted of treason except on the testimony of 2 witnesses to the same overt act, or on his confession in open court. (c) Sentence. Treason is a Class X felony.