Under Illinois law, a DUI charge can be upgraded to aggravated DUI – which is a felony offense – under the following circumstances:

• If you cause an accident in which a child passenger (under the age of 16) is injured.
• If you commit a second DUI offense while transporting a child passenger (under the age of 16).
• If you commit a DUI offense while driving a school bus with at least one minor (under the age of 18) on board.
• If you cause an accident in which one or more people suffer serious bodily harm, disfigurement, or permanent disability.
• If you cause a fatal accident that results in the death of one or more individuals.
• If you commit a DUI offense while driving on a suspended or revoked driver’s license (due to a previous DUI conviction or due to any other criminal conviction).
• If you commit a DUI offense while driving without a driver’s license or with an expired or invalid driver’s license.
• If you commit a DUI offense while driving without automobile insurance.
• If you commit a second DUI offense after having been convicted in the past of reckless homicide DUI or aggressive DUI resulting in death.

It should be noted that your third and subsequent DUI offenses in Chicago, Cook County, or Illinois will be prosecuted as a felony – even in the absence of any of the aforementioned aggravating factors.