Volkswagen, one of the world's largest car manufacturers, manipulated the pollutant emissions of cars sold in the United States in order to evade tests carried out by the American Environmental Protection Agency (Environmental Protection Agency, EPA). The accusation, later confirmed by the chief executive of the German carmaker Martin Winterkorn, had been brought by the EPA itself and relates to vehicles sold across the Atlantic between 2009 and 2015.

The Beetle, Golf, Jetta, Passat and Audi A3 were fitted with software on the control units of their diesel engines that falsified fine-particle and CO2 emissions results downwards. The cars could end up polluting between ten and forty times more than the limits set by law. The fraud appears to have been designed solely to increase engine power and performance. For each vehicle — approximately 482,000 were sold over those years — Volkswagen now faces a fine of $37,500, amounting to a total of $18 billion.

Volkswagen's share price fell by as much as 23 percentage points on the Frankfurt stock exchange on Monday 21 September alone, equivalent to approximately €15.6 billion wiped out in a single trading day. Winterkorn, who has led the company since 2007, said he was "deeply sorry" for having broken the trust of his customers and added that Volkswagen would do "everything necessary to make good the damage caused" by this extraordinary scandal.

The EPA has ordered the recall of the 482,000 tampered vehicles and has halted the sale in the United States of the five models fitted with the "incriminated" engine, including those badged as Audi, which is also part of the Volkswagen group. The troubles for the carmaker headquartered in the German city of Wolfsburg, however, are only just beginning. It now appears that several consumer associations wish to pursue damages claims, as do the United States Department of Justice and the German government, both of which could open further investigations.