55 ILCS 5/3-6033

The sheriff of any county or the corporate authorities of any municipality may authorize, empower, employ, or permit a person to act as deputy sheriff or special policeman for the purpose of preserving the peace who is a citizen of the United States, who is legally authorized under federal law to work in the United States and is authorized under federal law to obtain, carry, or purchase or otherwise possess a firearm, or who is an individual against whom immigration action has been deferred by the U.S. Citizenship and Immigration Services under the federal Deferred Action for Childhood Arrivals (DACA) process and is authorized under federal law to obtain, carry, or purchase or otherwise possess a firearm.