Martin Winterkorn, the former CEO of Volkswagen AG, has been charged with conspiracy and wire fraud over the diesel scandal.

The Volkswagen scandal, which started more than 3 years ago, reached the tipping point where Mr. Winterkorn resigned from his role at Volkswagen in September of 2015, following revelations that company had been cheating on diesel engine emissions tests, using software that was designed to deceive regulators.

A few days after his resignation, the company confessed to outfitting 11 million cars with a device that was designed to cheat at emissions testing.

The charges reopen the question of whether other senior Volkswagen executives knew about the scandal, although company initially claims that the cheating was only known by lower-level executives. Interestingly, the Justice Department says that “the indictment of Winterkorn alleges that he was informed of VW’s diesel emissions cheating in May 2014 and again in July 2015. The indictment further alleges that Winterkorn, after having been clearly informed of the emissions cheating, agreed with other senior VW executives to continue to perpetrate the fraud and deceive U.S regulators.

However, Winterkorn is unlikely to face U.S. authorities. A few days ago, Germany’s Federal Justice Ministry said it does not extradite German nationals to countries outside the European Union.