The Detroit News. According to the law, tinting on the windshield and driver and front passenger windows can come down no more than four inches with a reflection rate of no more than 35 percent.
Light transmission is the amount of light let into the car through the tinting.
There is no law that says tinting has to let light through at all, although it would make things very dark for the person inside the vehicle. That's all perfectly legal. It might be legal, but it doesn't make a police officer's job very easy, according to Sgt. On night stops, you come up with a flashlight in your hand and your spotlight on the vehicle. If someone back there wants to do you harm, then you're a sitting duck.