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Volkswagen Violations

Laws and Regulations related to Volkswagen Violations

U.S. Authorities and Regulations   

Defeat Devices

Section 203 (a)(3)(b) of the Clean Air Act (CAA), 42 U.S.C. Sec. 7522(a)(3)(b), prohibits the manufacture, selling, or installation of any device that intentionally circumvents EPA emission standards by bypassing, defeating, or rendering inoperative a required element of the vehicle’s emissions control system.

Section 203 (a)(1) of the same Act also prohibits the sale of motor vehicles or engines that are not covered by valid certificates of conformity.

40 CFR Part 86, Subpart A contains the regulatory language pertaining to defeat devices.


EPA has the authority under Section 207(c)(1) of the CAA to require a manufacturer to issue a recall when EPA determines that a substantial number of vehicles do not conform to EPA regulations. Section 203(a)(4)(B) of the CAA makes clear that it is a prohibited act for manufacturers to fail or refuse to comply with an ordered recall by EPA.

40 CFR Part 85 Subpart S contains the regulations (40 CFR 85.1801-85.1808) regarding recall requirements for light duty-vehicles.

U.S. NOx Emission Standards for Light Duty Cars and Trucks

EPA has introduced progressively more stringent light-duty vehicle emission standards since the 1970 CAA established the Agency and its authority to regulate pollution from motor vehicles. EPA’s Tier 1 emission standards were in effect from the mid-1990s through the mid-2000s before being replaced by EPA’s Tier 2 standards which began phasing in with the 2004 model year. The Volkswagen vehicles listed in the Notice of Violation were subject to the Tier 2 emission standards. The most recent stringency increase was promulgated with the Tier 3 regulations, which take effect starting in model year 2017.

EPA’s programs include a number of standards and program flexibilities such as emissions averaging which can make it difficult to simply compare the emission standards between program phases. With that caveat, the Tier 1 NOx standard applicable to diesel cars in the mid-1990s to mid-2000s was 1.25 g/mile (at 100,000 miles) while the Tier 2 NOx standard that the Volkswagen Jetta diesel was certified to is 0.07 g/mile (at 120,000 miles).

A full summary of EPA light-duty emission standards

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