EPA Exposes Volkswagen Dieselgate: 11 Million Cars with Emissions Defeat Devices

On September 18, 2015, the Environmental Protection Agency issued a Notice of Violation to Volkswagen Group, exposing one of history’s largest corporate environmental frauds: VW had intentionally installed “defeat device” software in approximately 11 million diesel vehicles worldwide (590,000 in the U.S.) spanning model years 2009-2016. The sophisticated software detected when vehicles were undergoing emissions testing and activated full pollution controls only during tests, while allowing vehicles to emit nitrogen oxides at up to 40 times the legal limit during normal driving.

The scandal revealed catastrophic regulatory capture and EPA oversight failures. Independent researchers at West Virginia University, commissioned by the International Council on Clean Transportation, detected the excessive emissions in 2013 and reported findings to CARB and EPA in May 2014—showing VW diesels exceeded NOx limits by factors of 5 to 35. Despite this evidence, it took 17 months until September 3, 2015, for Volkswagen to admit to regulators it had deliberately installed defeat devices, and the EPA only issued its violation notice on September 18, 2015.

The EPA’s failure to detect the fraud for six years (2009-2015) despite VW selling hundreds of thousands of fraudulent vehicles demonstrates severe regulatory inadequacy. The EPA’s emissions testing procedures were highly predictable and hadn’t adapted to technological advances, allowing VW to exploit loopholes by designing software that recognized test conditions. EPA resources remained static even as vehicle populations and oversight responsibilities increased, creating what investigators called a “post-hoc enforcement” framework rather than preventive oversight. The agency relied heavily on manufacturer self-certification rather than independent verification.

VW ultimately pleaded guilty to three criminal felony counts, agreed to a $2.8 billion criminal penalty, and settled for a total exceeding $30 billion in fines, buybacks, and compensation. CEO Martin Winterkorn resigned, and the scandal fundamentally exposed how regulatory capture—interconnected interests between manufacturers and agencies, combined with inadequate resources and outdated testing protocols—enabled a profit-driven corporation to systematically poison public health for years while regulators failed to detect the fraud.