75 ILCS 16/1-20

(a) A person who violates an ordinance of a district that provides for a penalty is guilty of a petty offense and shall be fined not less than $25 nor more than $100 for each offense. (b) All actions for violations shall be governed by and processed as in the case of violations of municipal ordinances. (c) All fines for violations of ordinances involving injury to or failure to return any book, material, or property belonging to the library shall be paid into the Library Fund established under Section 35-25. All fines and penalties for the commission of injury upon the library or the grounds or other property of the library shall be paid into the fund of the public agency or body enforcing those ordinances.