Illinois Statutes Chapter 50. Local Government § 355/5-50. Audit referrals; restrictions

(a) Upon entering into a contract with a municipality or county, a third party shall be prohibited from communicating directly or indirectly in any manner with a taxpayer known or believed to be operating within that municipality or county about any matters directly or indirectly related to, or covered by, the contract.

(b) If, based on a review of the financial information provided by the Department to a municipality or a county, or provided by a municipality or county to a registered third party, a municipality, county, or third party discovers that local retailers' or service occupation tax may have been underpaid, then it may refer the matter to the Department for a limited-scope audit in accordance with Article 10 of this Act.

(c) With respect to taxes administered by the Department, units of local government and third parties are not authorized to (i) access, review, or compel the production of taxpayers' actual tax returns or (ii) access, review, or compel the production of taxpayers' books and records.

(d) With respect to taxes administered by the Department, units of local government and third parties are prohibited from (i) engaging in an audit of any taxpayer, (ii) assessing tax against any taxpayer, (iii) engaging in collection actions against any taxpayer for the tax, or (iv) engaging in any other action related to such taxes that is assigned by law to the Department.

(e) A local government shall not share any financial information received with another local government or another third party. Further, a local government may not share the findings of a third party with another local government or another third party.