A federal grand jury in Detroit indicted former Volkswagen CEO Martin Winterkorn on charges stemming from the company’s diesel emissions cheating scandal.

The four-count indictment was unsealed May 3 and charges the former executive with three counts of wire fraud and one of conspiring with other senior VW executives and employees to violate the U.S. Clean Air Act. He was indicted in March. Former VW CEO Martin Winterkorn. Credit: ReutersVolkswagen admitted to programming its diesel engines to turn on pollution controls when being tested and turning them off when on the road.

If convicted, Winterkorn faces up to five years in prison and a $250,000 fine on the conspiracy charge and up to 20 years in prison and a $25,000 fine on the wire fraud charges. He is the ninth person charged by U.S. authorities in the case. Two have pleaded guilty and are serving jail time, while six others remain in Germany.

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“Volkswagen deceived American regulators and defrauded American consumers for years,” Matthew Schneider, the U.S. Attorney for the Eastern District of Michigan, said in a statement. “The fact that this criminal conduct was allegedly blessed at Volkswagen’s highest levels is appalling.”

In November 2017, Oliver Schmidt, VW’s compliance liaison with U.S. regulators, was sentenced to seven years in prison. He had earlier pleaded guilty to one count of conspiracy to defraud the U.S. and another of violating the Clean Air Act.

The U.S. government believes Winterkorn is in Germany, whose constitution forbids extraditing its citizens other than to another European Union member state or to an international court.

Prosecutors in the city of Braunschweig said in January of 2017 that Winterkorn was among 37 suspects being investigated in a criminal probe related to the emissions scandal. A statement said prosecutors were investigating him on suspicion of fraud and false advertising.

Winterkorn testified in the German parliament that he didn’t learn of the problem until shortly before U.S. investigators announced it in September 2015.

The indictment alleges that Winterkorn was told of the emissions cheating in May of 2014 and again in July of 2015, yet “agreed with other senior VW executives to continue to perpetrate the fraud and deceive U.S. regulators.”

The plot was discovered when the International Council on Clean Transportation, which works with governments to control emissions, paid for emissions testing on two diesel VWs. The study of on-road performance found that one emitted up to 35 times the allowable amount of toxic nitrogen oxide.