It may be a new year, but that doesn’t mean Volkswagen can wash its hands of the ongoing diesel emissions scandal affecting 11 million vehicles. Today, the U.S. Dept. of Justice filed a civil lawsuit against the carmaker over its use of “defeat devices” to cheat on emissions tests.

The complaint [PDF], filed today in a federal court in Michigan, alleges violations of the Clean Air Act for the approximately 500,000 VW “clean diesel” vehicles sold in the U.S. The carmaker could face upwards of billions of dollars in penalties if found liable.

“The United States will pursue all appropriate remedies against Volkswagen to redress the violations of our nation’s clean air laws,” Assistant Attorney General John Cruden, head of the departments environment and natural resources division, said.

The Dept. of Justice, which was rumored to be considering filing a criminal complaint against the company in September, can still pursue criminal charges against VW, a DOJ official tells Reuters.

In September, the Environmental Protection Agency, along with the California Air Resources Board, issued a notice of compliance to VW after determining that nearly 500,000 diesel 4-cylinder model year 2009 to 2015 Volkswagen and Audi vehicles contained a “sophisticated software algorithm,” programmed to detect when the car is undergoing official emissions testing, and to only turn on full emissions control systems – the temperature conditioning mode – during that testing.

However, the effectiveness of these vehicles’ pollution emissions control devices is greatly reduced during all normal driving situations.

“This results in cars that meet emissions standards in the laboratory or testing station, but during normal operation, emit nitrogen oxides, or NOx, at up to 40 times the standard,” the notice states.

Under the Clean Air Act, vehicle manufacturers are required to certify to the EPA that their products will meet applicable federal emission standards to control air pollution, and every vehicle sold in the U.S. must be covered by an EPA-issued certificate of conformity.

Motor vehicles – such as the Volkswagen models in question – equipped with defeat devices, which reduce the effectiveness of the emission control system during normal driving conditions, cannot be certified.

Days later, VW admitted that nearly 11 million vehicles contained the devices worldwide, and issued a stop sale on the affected cars.

From there things have only gotten worse for VW. Consumers and other groups have filed lawsuit against the company, and investigators have found additional defeat devices on other VW, Audi, and Porsche models.

U.S. files civil suit against Volkswagen for environment violations [Reuters]

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