After months of investigations, the US Justice Department has just filed a civil lawsuit against Volkswagen AG for violating the Clean Air Act.

In September, it emerged that the Volkswagen Group had installed almost 600,000 vehicles in the U.S. and millions more around the world with software to cheat diesel emissions testing.

Through the lawsuit, the German company could be slapped with fines in excess of $90 billion, if a maximum fine of $37,500 is applied to each cheating car produced and numerous other fines are received. This $90 billion figure is significantly more than the initial $18 billion in fines government regulators said Volkswagen could face.

The lawsuit has been filed on behalf of the Environmental Protection Agency and claims VW has violated the Clean Air Act on four counts. Two of those counts are the tampering of emissions control systems and the marque’s failure to report any of its violations.

The civil lawsuit is being filed in the Eastern District of Michigan and will then be transferred to Northern California. Officials from the Justice Department claim that VW knew they were violating the law.

As the government only needs to prove that emissions cheating occurred and not the level of deception on the part of Volkswagen, the lawsuit is expected to easily be won. Volkswagen is most likely to then call for a lower penalty.

Making matters worse for VW is that the Justice Department could also press criminal charges against Volkswagen for misleading both consumers and regulators in the United States. That could lead to further fines.

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