Window Tint Laws: The Basics
Some people believe that vehicle window tinting keeps the temperature inside a car cooler, while others just think window tinting makes a car look cooler. And in some cases, drivers or passengers may have a legally recognizable medical need to have tinted vehicle windows, even when the tint level would otherwise violate their state's vehicle code.
Whatever your reason for wanting tinted windows on your car, truck, or other passenger vehicle, you should get familiar with laws that regulate vehicle window tinting, as well as exemptions under those laws. Here you will find basic information on window tinting laws, "medical necessity" exemptions, and more. (also see: State-Specific Information on Vehicle Window Tint Laws)
Window Tinting Basics
What is "window tinting" when it comes to cars, trucks, SUVs, and other passenger vehicles? In practical terms, "window tinting" refers to methods that prevent certain levels of light from passing through the safety glass -- meaning the windshield, side windows, and rear window of a vehicle.
The safety glass on most newer cars and passenger vehicles has been coated or treated so that some degree of window tinting is in place, to keep out harmful ultra-violet (UV) rays. This tinting is done during the manufacturing process, and is almost always in compliance with federal and state window tinting laws and regulations.
But window tinting can also be done after a vehicle has been manufactured and sold (or "after-market," in the vernacular). And it is when these modifications are made -- often by a private "customizing" company or by the vehicle's owner him/herself -- that window tint laws are most often violated.
Window Tint Laws
Vehicle window tinting is almost always regulated under state law, and the applicable statutes can usually be found in a state's vehicle or traffic code. The applicable vehicle code section in your state may discuss vehicle window tinting as "Material Obstructing or Reducing Driver's View" (in California), "Windshields and windows obscured by non-transparent materials" (in Massachusetts), or "Sun-shading or tinting films or applications" (in Virginia).
Your state's vehicle code may consider "window tinting" to include:
- Heat-shrinking a tinted sheet of film to a vehicle's windshield or window, usually on the inside surface of the glass. This is usually done "after-market."
- "Shade bands," usually meaning a thin, horizontal strip of tint at the top of a vehicle's windshield, where it meets the vehicle roof.
- Sunscreen devices that are temporarily affixed to the inside surface of a vehicle's windshield, side windows, or rear window (i.e. a plastic shade device on a passenger side window, held in place with suction cups).
Most state laws on vehicle window tinting are concerned mainly with the levels of "light transmittance" or "luminous reflectance" that the vehicle's safety glass allows -- meaning how much light can get through and how much visibility the glass allows.
So, if the windows on a vehicle are tinted to such a degree that the amount of light that can come through is below the amount identified under state law (i.e. 75% light transmittance), then the vehicle does not comply with the state's vehicle code, and the vehicle's owner will be issued a citation. Many state vehicle codes contain different light transmittance requirements for the vehicle's front windshield, when compared with standards for the vehicle's side and rear windows.
Finally, most state vehicle codes specify that no vehicle windshield or window may contain opaque or mirrored material, or "one-way" glass.
Does Your Vehicle's Window Tinting Violate Your State's Laws?
Measurements like "light transmittance" and "luminous reflectance" can be difficult to understand, let alone calculate with any level of confidence. So you may want to have your vehicle inspected to determine whether it is in compliance with your state's window tint laws. A government inspector or a private licensed professional can inspect your vehicle -- most likely using a light transmission-measuring device called a photometer -- to determine if your vehicle's safety glass meets the "light transmittance" or "luminous reflectance" standards of your state's window tint laws.
To learn where you can have your vehicle's window tinting inspected, start by contacting your state's department of motor vehicles (DMV) office. And remember, even if your vehicle's safety glass is currently in compliance with your state's window tint laws, that could change if you move to another state.
"Medical Necessity" Exemptions to Window Tint Laws
Many state vehicle window tinting laws contain exemptions for people (drivers or frequent passengers in a specific vehicle) with a valid medical or vision-related condition that requires the limitation of exposure to sunlight. Examples of medical conditions that may qualify under these exemptions are:
- Sunlight allergy
Typically, if a vehicle is stopped for a window tint-related traffic violation, in order to qualify for the medical exemption and avoid a citation, the affected driver or passenger must present the law enforcement officer with documentation that:
- Identifies the medical necessity (this can be a prescription or detailed letter from a medical professional);
- States the specific amount of sunlight exposure (i.e. minimum percentage of light transmittance reduction) that will satisfy the medical needs of the affected driver or passenger;
- Contains a prescription expiration date or permit duration;
- Identifies the specific vehicle(s) to which the "medical necessity" window tint exemption applies.
Following are some examples of state-specific applications for "medical necessity" window tint exemptions:
- State of Georgia Application for Exemption to the Window Tint Law (Georgia Department of Public Safety) [PDF file]
- State of Vermont Application for Window Tint Medical Exemption (Vermont Department of Motor Vehicles) [PDF file]
To find out whether such an exemption is available in your state, start by contacting your state's department of motor vehicles (DMV) office.
Need Legal Guidance on Window Tinting Laws? Contact an Attorney
Whether you need window tinting for legitimate health reasons or just think it looks cool, make sure you understand the laws in your state first. If your situation is particularly complex, you may want to speak with an attorney who handles traffic law matters.