70 ILCS 200/155-32

The State and all counties, cities, villages, incorporated towns and other units of local government and public bodies, and public officers of any thereof; all banks, bankers, trust companies, savings banks and institutions, building and loan associations, savings and loan associations, investment companies and other persons carrying on an insurance business; and all executors, administrators, guardians, and trustees and other fiduciaries may legally invest any sinking funds, moneys or other funds belonging to them or within their control in any bonds issued pursuant to this Article.