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Interpretation ID: 2637y

Ms. Betsy Dittemore
Legislative Liaison
Iowa Department of Public Safety
Office of the Commissioner
Wallace State Office Building
Des Moines, Iowa 50319

Dear Ms. Dittemore:

Thank you for your letter regarding a bill introduced in the Iowa Senate that, among other features, would establish light transmittance limits for "sunscreening devices" that may be applied to the windows of motor vehicles operated in Iowa. I apologize for the delay in this response. You requested our office's interpretation about whether provisions of this bill would violate or be preempted by Federal Motor Vehicle Safety Standard No. 205, Glazing Materials (49 CFR 571.205).

As you are aware, this agency is authorized by section 103 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1392) to issue safety standards applicable to new motor vehicles and certain items of motor vehicle equipment. One of the standards that we have issued under this authority is Standard No. 205, which applies to all new vehicles and all new glazing materials for use in motor vehicles. Among the requirements set forth in Standard No. 205 are specifications for minimum levels of light transmittance (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)) specifies that no person may manufacture, import, or sell any vehicle in the United States unless it is in conformity with all applicable safety standards. Pursuant to section 108(b)(1) of the Safety Act (15 U.S.C. 1397(b)(1)), this prohibition no longer applies after the vehicle is sold to a consumer. However, both before and after the first sale, 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 part, any device or element of design installed on or in a notor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard . . . ."

In the case of windows on a passenger car, this provision of Federal law means that no manufacturer, dealer, distributor, or repair business could install window tinting film that would result in a light transmittance of less than 70 percent for any window of the car, because such action would "render inoperative" the vehicle's compliance with Standard No. 205. This same provision of Federal law prohibits a service station from permanently removing safety belts or permanently disconnecting brake lines on motor vehicles.

Please note that the Safety Act does not apply to the actions of vehicle owners. Vehicle owners may alter their own vehicles and operate them on the highways as they please, even if the vehicle's windows no longer comply with the requirements of Standard No. 205. Hence, no provision of a Federal statute or this agency's regulations prevents individual vehicle owners themselves from tinting the windows on their vehicles.

The individual States, however, have the authority to regulate the modifications that vehicle owners may make to their own vehicles and to establish requirements for vehicles operated or registered in that State. The Iowa Senate bill enclosed with your letter appears to be an attempted exercise of this inherent authority.

You asked for comments on whether this bill, if adopted as law in Iowa, would be preempted by Standard No. 205. I assume you were referring to the provision in this Iowa bill that would prohibit the operation of motor vehicles required to be registered in the State of Iowa if the vehicle has a "sunscreening device" on the front side windows with light transmittance of less than 35 percent or on the rear window and side windows behind the driver with light transmittance of less than 20 percent. Since the original glazing on the vehicle could have had light transmittance of as little as 70 percent, this provision would permit overall light transmittance levels of as low as 25 percent for the front side windows and 14 percent for the rear windows.

This provision in the Iowa bill, and similar provisions in statutes adopted by other States, does not purport to legitimize conduct -- the rendering inoperative of glazing by firms installing window tinting -- that is illegal under Federal law. In other words, firms installing window tinting that results in light transmittance of less than 70 percent on any window of a passenger car would have violated the "render inoperative" provision in Federal law, even if Iowa had in place a statute that would permit persons to operate and register vehicles whose windows had light transmittance that was far lower. 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 Iowa 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 Iowa.

Thus, there does not appear to be any legal conflict between Federal law and this Iowa bill, and Iowa would be free to enforce the provisions of this bill if it is enacted into law. We would, however, urge the State of Iowa to carefully consider the adverse safety consequences that would result from enacting this bill into law. NHTSA has determined that a 70 percent light transmittance minimum for new vehicles is the appropriate level to assure motor vehicle safety. Your letter indicated that Iowa had also adopted this 70 percent light transmittance minimum as a State requirement for new vehicles. It is not clear why the State of Iowa would conclude that the safety need that justifies requiring not less than 70 percent light transmittance in new vehicles is satisfied by allowing light transmittance levels as low as 25 and 14 percent in vehicles 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

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