We lived in Illinois before moving to Florida 5 years ago. Back then they didn't tolerate any tint unless it was factory or the driver had a form from a doctor. I used to see cars pulled over all the time and the people taking a razor blade to the windows. I guess they changed the tint law in 2015 allowing people to go with 35% on all windows except the windshield. The reason for the strict law is cops could not see the people in the car they pulled over and were getting shot at walking up to the window or see a gun pointed at them when the window was rolled down. It was really bad where we lived, bunch of crazy stupid people. One thing that pissed me off about the law was state troopers were allowed 5% all the way around. I don't see them pulling a gun or shooting someone thru the glass just for fun but what was good for everyone else should have been good for them.