50 ILCS 150/10
All local public agencies shall, by resolution or ordinance, regulate the reimbursement of all travel, meal, and lodging expenses of officers and employees, including, but not limited to: (1) the types of official business for which travel, meal, and lodging expenses are allowed; (2) maximum allowable reimbursement for travel, meal, and lodging expenses; and (3) a standardized form for submission of travel, meal, and lodging expenses supported by the minimum documentation required under Section 20 of this Act. The regulations may allow for approval of expenses that exceed the maximum allowable travel, meal, or lodging expenses because of emergency or other extraordinary circumstances. On and after 180 days after January 1, 2017 (the effective date of this Act) , no travel, meal, or lodging expense shall be approved or paid by a local public agency unless regulations have been adopted under this Section.
50 ILCS 150/10