Window tinting can filter out harmful UV rays and keep the interior of your car a few degrees cooler, but a tint that is too dark can impair your visibility and make driving, especially at night, more dangerous.
Tinted windows can also prevent a driver from communicating their intentions to other drivers and pedestrians, and vice versa, making driving inherently less safe. The Mercury News reports that having illegal window tint can even impact liability in a car accident.
In the case of an emergency where a front window may need to be broken to escape from the vehicle, the film can make it more difficult to remove the glass. Aftermarket tint is made of a strong mylar film, which can be difficult to rip without a knife, notes John Bridgwater, master mechanic and owner of two AAA Approved Auto Repair Centers in the Bay Area. Using a traditional spring loaded escape tool, a tempered glass window shatters into many small cubes. But the tinting film will prevent this from happening the way it was intended too, says Bridgwater.
Because of its potential impact on safety, window tinting is controlled with specific laws in most states and is illegal if applied to windshields and front windows in California.