All states have traffic laws that limit the amount of window tint on motor vehicles—often by specifying the amount of visible light transmission (VLT) that is required. VLT is the amount of light that is transmitted through the window and into the vehicle. For example, a 70%VLT means that 70% of light will pass through the window and 30% will be reflected. Thus, a lower VLT indicates a darker film or tint.

Another term to know is visual light reflection (VLR)—which is the opposite of VLT. VLR is the amount of solar energy that is reflected off the glass and away from the inside of the vehicle.

In most states tickets or citations for illegal window tint are known as fix-it tickets and the ticket or citation will indicate that it is a correctable violation of traffic laws. For example, if you fix the window tint problem within the required period, pay a small fine, and get the signature of an authorized person (a local police officer) the court may dismiss the ticket.

But if you fail to fix the window tint problem within the required period you must pay the fine for the violation and you may be issued another ticket that will be part of your driving record. And if you fail to pay the ticket or appear in court on the hearing date the court may issue a warrant for your arrest.

Window tint laws vary from state to state and some states have exemptions for certain vehicles such as limousines and recognize medical exemptions when the driver has a written statement from a licensed medical doctor, ophthalmologist, or optometrist.

In Minnesota, window tint laws are regulated under Minnesota Statutes Section 169.71. The state specifies that the amount of light allowed to pass through car window tint (VLT) must be 50% or more on all side and rear windows for passenger vehicles. For multi-purpose vehicles, such as SUVs and vans, the front side windows must also have a VLT of 50% or more, but the rear windows can have any level of darkness. The law also requires a minimum VLT of 50% for the windshield, but only for the top six inches. Reflective tint is allowed but must not be more than 20% reflective. Minnesota recognizes medical exemptions for individuals who require a lower VLT due to a medical condition, and they must carry documentation from a licensed physician. Violations of the window tint laws are considered misdemeanors, and if not corrected, can lead to fines and potentially impact one's driving record. It is important for vehicle owners to comply with these regulations to avoid 'fix-it' tickets and potential legal consequences.