Interpretation ID: 2636y
Chief, Vehicle Services
State of Delaware
Department of Public Safety
Division of Motor Vehicles
P. O. Box 698
Dover, Delaware, 19903
Dear Mr. Eanes:
This is in response to your letter asking whether very darkly tinted rear windows that obscure the center highmounted stop lamp (CHMSL) required in passenger cars manufactured on or after September 1, 1985 would violate any Federal laws or regulations. Let me begin by apologizing for the delay in this response. I am pleased to have this opportunity to explain our laws and regulations for you.
The National Traffic and Motor Vehicle Safety Act (the Safety Act) authorizes this agency to issue safety standards applicable to new motor vehicles and new items of motor vehicle equipment. We have exercised this authority to issue two safety standards that are relevant to your question. The first of these is Standard No. 108, Lamps, Reflective Devices, and Associated Equipment (49 CFR 571.108), which applies to all new vehicles and new replacement equipment for motor vehicles. Among the requirements set forth in this Standard is a requirement for all passenger cars manufactured on or after September 1, 1985 to be equipped with a CHMSL of specified minimum size, brightness, and visibility from the range of locations set forth in the standard. The second relevant standard is Standard No. 205, Glazing Materials (49 CFR 571.205). This standard applies to all new vehicles and all new glazing for use in motor vehicles, and includes specifications for minimum levels of light transmittance of the glazing (70 percent light transmittance in areas requisite for driving visibility, which includes all windows in passenger cars).
Section 108(a)(1)(A) of the Safety Act (15 U.S.C. 1397(a)(1)(A)) provides that no person may manufacture or sell any vehicle unless it is in conformity with all applicable safety standards. A new passenger car with a rear window tinted so darkly that the CHMSL was not easily visible would probably not be in conformity with Standards No. 108 and 205, and so could not legally be manufactured or sold in the United States. However, this prohibition on the manufacture or sale of a nonconforming vehicle does not apply after a vehicle is first sold to a consumer.
Both before and after the first sale of a vehicle, section 108(a)(2) of the Safety Act (15 U.S.C. 1397(a)(2)) provides that: "No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or in part, any device or element of design installed on a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard . . ." If any of the listed commercial entities were to install tint film or otherwise darken the rear windows on passenger cars so that the light transmittance of that window plus the darkening material was below 70 percent, those entities would be "rendering inoperative" the light transmittance of the rear window of the car, in violation of Federal law. This same prohibition in Federal law makes it unlawful for a service station to permanently remove the safety belts or permanently disconnect the brake lines on a car.
Please note that the Safety Act does not apply to the actions of individual vehicle owners. Vehicle owners may alter their own vehicles and operate them on the highways as they please, even if the vehicle no longer complies with the safety standards after such alterations. Hence, no provision of the Safety Act or our safety standards makes it unlawful for vehicle owners themselves to tint or otherwise darken the rear window of their car so that its light transmittance is below 70 percent and/or its CHMSL is obscured.
The individual States, however, do have authority to regulate the modifications that vehicle owners may make to their own vehicles. The States also have the authority to establish requirements for vehicles to be registered or operated in that State.
You indicated in your letter that the State of Delaware "allows vehicle rear windows to be tinted as dark as the owner desires." While I am not familiar with Delaware law, I assume that this statute, and similar statutes adopted by other States, does not purport to legitimize conduct -- the rendering inoperative of glazing and CHMSLs by firms installing window tinting -- that is illegal under Federal law. In other words, any commercial firms installing window tinting that results in light transmittance of less than 70 percent and/or reduces the required brightness of the CHMSL would have violated the "render inoperative" provision in Federal law, even if Delaware permits individual owners to make such modifications themselves and to register and operate vehicles with rear windows and CHMSLs that would not comply with the requirements of the Federal safety standards for new vehicles. Conversely, the Federal law setting requirements for the manufacture and sale of new vehicles and limiting the modifications commercial enterprises can make to those vehicles does not prohibit the State of Delaware from establishing lesser limits on owner modifications to their own vehicles and as the minimum requirements for vehicles to be operated and registered in the State of Delaware.
Thus, there does not appear to be any legal conflict between Federal law and Delaware law, and Delaware would be free to enforce the provisions of its law. We would, however, urge the State of Delaware to carefully consider the adverse safety consequences that will result from the provision of its law. NHTSA has determined that a 70 percent light transmittance minimum for new vehicles is the appropriate level to assure motor vehicle safety, and that the CHMSL on passenger cars enhances motor vehicle safety. It is not clear why the State of Delaware would conclude that the safety need that justifies requiring not less than 70 percent light transmittance and CHMSLs in new passenger cars is satisfied by allowing far lower light transmittance levels and lower-brightness CHMSLs in passenger cars to be operated in the State.
I hope that this information is helpful. If you have any further questions or need additional information about this topic, please feel free to contact Dorothy Nakama of my staff at this address or by telephone at (202) 366-2992.
Sincerely,
Paul Jackson Rice Chief Counsel /ref:108#205#VSA d:7/3l/90