Volkswagen was fined by U.S. authorities in 2017 over its emissions-cheating diesel scandal.
The U.S. Environmental Protection Agency announced in 2015 that Volkswagen diesel vehicles used software designed to recognize emissions testing. During laboratory tests, the vehicles reduced certain emissions, while normal driving produced much higher nitrogen-oxide pollution.
Volkswagen admitted the use of defeat-device software in millions of diesel vehicles worldwide. In the United States, the company agreed in 2017 to plead guilty to criminal charges and pay about $4.3 billion in criminal and civil penalties. Earlier settlements had already included vehicle buybacks, repairs, and compensation.
The scandal damaged Volkswagen’s reputation and intensified scrutiny of diesel technology and real-world emissions testing. “Dieselgate” is a common nickname, but the underlying issue was the use of software to evade regulatory testing rather than a simple mechanical defect.