220 ILCS 5/5-107
Any person who shall wilfully make any false entry in the accounts, or in any record or memoranda or by any other means or device falsify the record of any such account, record or memoranda, or who shall willfully neglect or fail to make full, true, and correct entries in such accounts, records, or memoranda of all facts in transactions appertaining to the business of the public utility, or shall keep any accounts or record other than those prescribed or approved by the Commission, shall be guilty of a Class A misdemeanor.
If any such books, accounts, records or memoranda shall have been preserved for a period of at least three years, a public utility may with the consent of the Commission destroy such of them as in the judgment of the Commission may properly be destroyed.
220 ILCS 5/5-107