# Volkswagen secretly programmed millions of diesel cars to cheat emissions tests

**Verdict: Proven.** This is not a theory to weigh but a documented corporate conspiracy. Between 2009 and 2015 Volkswagen fitted roughly 11 million diesel vehicles worldwide with 'defeat device' software that recognized when a car was on a test bench and switched to a clean mode, while on the open road the same cars emitted up to about 40 times the legal limit of nitrogen oxides. Volkswagen admitted it after a US EPA notice of violation, pleaded guilty to three federal felonies, and has paid well over 30 billion dollars in fines, settlements, and buybacks. Individual executives and engineers were indicted; several were convicted. The remaining questions are narrow: how far up the chain knowledge ran, and how much lasting harm the extra pollution caused.

Category: Secret Societies & Power · Era: 2010s · First circulated: September 2015, when the US Environmental Protection Agency issued a public notice of violation; the cheating itself ran from roughly 2009 to 2015 and grew out of on-road testing published by the ICCT in 2014 · Believed by: Universally accepted as established fact, admitted by Volkswagen and confirmed by regulators and courts in the United States and Germany; what is still argued is the exact chain of internal responsibility, not whether the fraud occurred
URL: https://theconspiratory.com/theory/volkswagen-dieselgate

## Summary
For roughly six years Volkswagen sold diesel cars marketed as clean that were built to lie. Hidden software detected the conditions of an official emissions test and quietly turned on the full pollution controls; the moment the car sensed it was back on a real road, it switched much of that treatment off and poured out nitrogen oxides at up to about 40 times the legal limit. Around 11 million vehicles worldwide carried the defeat device. The scheme unraveled after independent researchers measured the gap on the road, the US EPA issued a notice of violation in September 2015, and Volkswagen admitted the cheating. What followed is on the record: a guilty plea to three US felonies, more than 30 billion dollars in penalties and settlements, the resignation and later indictment of chief executive Martin Winterkorn, and prison terms for engineers and managers on both sides of the Atlantic. This case file lays out the proven record and keeps it separate from the questions that genuinely remain open.

## The claim
That Volkswagen deliberately installed illegal 'defeat device' software in millions of diesel vehicles to detect and pass government emissions tests while emitting far more pollution than the law allowed in normal driving, then concealed the scheme from regulators and customers for years.

## Origin and timeline
- 2007–2009: Under pressure to sell diesels in the United States without the cost of full emissions hardware, Volkswagen engineers develop and deploy engine-control software that can recognize the specific conditions of a laboratory test. US regulators would later date the affected 2.0-liter vehicles from model year 2009 onward.
- 2013: The International Council on Clean Transportation (ICCT) commissions West Virginia University's Center for Alternative Fuels, Engines and Emissions (CAFEE) to measure real-world emissions from diesel cars sold in the United States, using portable on-board testing equipment rather than a lab.
- 2014-05: The ICCT publishes the West Virginia University findings: two of three tested vehicles, both Volkswagens, emit far more nitrogen oxides on the road than in the lab. The results are reported to the California Air Resources Board (CARB) and the EPA, which open inquiries.
- 2014–2015: For more than a year Volkswagen offers technical explanations and a voluntary recall rather than admitting the software. Regulators press for answers and CARB threatens to withhold certification for 2016 models, which finally forces the company to concede the presence of a defeat device.
- 2015-09-18: The EPA issues a public notice of violation of the Clean Air Act, stating that roughly 482,000 Volkswagen and Audi 2.0-liter diesels sold in the US since 2009 contain software that circumvents emissions standards, with on-road nitrogen oxide output up to about 40 times the legal limit.
- 2015-09-22: Volkswagen admits that around 11 million vehicles worldwide are fitted with the same type of defeat-device software and sets aside billions of euros to cover the fallout. The scandal is dubbed 'Dieselgate' in the press.
- 2015-09-23: Chief executive Martin Winterkorn resigns, saying he is 'shocked' by the events and accepting responsibility as head of the company while denying personal wrongdoing.
- 2016-09: James Liang, a Volkswagen engineer, pleads guilty in US federal court to conspiracy and becomes a cooperating witness, the first individual to admit involvement in the scheme.
- 2017-01-11: The US Department of Justice announces that Volkswagen has agreed to plead guilty to three criminal felony counts and pay 4.3 billion dollars in combined criminal and civil penalties. Six executives and employees are indicted; the company also accepts an independent monitor for three years.

## The evidence, claim by claim
- Claim: Volkswagen deliberately installed software designed to detect and defeat emissions testing.
  Evidence: Documented and admitted. The EPA's September 2015 notice of violation described software that sensed test conditions (steering, throttle, and how the wheels were turning) and switched emissions controls to full strength only during testing. Volkswagen conceded the defeat device existed, and in its 2017 guilty plea the company formally admitted that it had designed, deployed, and concealed the software. This is not an inference from circumstantial data; it is the company's own admission on the criminal record.
- Claim: On the road, the affected cars emitted far more nitrogen oxides than the law allowed.
  Evidence: Established by measurement and by regulators. The West Virginia University on-road tests commissioned by the ICCT first flagged the gap in 2014. The EPA quantified it: with the controls dialed down in normal driving, the 2.0-liter cars emitted nitrogen oxides at up to roughly 40 times the applicable standard. Nitrogen oxides contribute to smog and respiratory harm, which is why the limit exists and why the deception mattered beyond the paperwork.
- Claim: The scheme was large in scale and ran for years across multiple markets.
  Evidence: Confirmed by the company and by multiple governments. Volkswagen stated in September 2015 that about 11 million vehicles worldwide carried the defeat-device software, including roughly 482,000 in the United States and millions across Europe. US authorities dated the affected American vehicles from model year 2009 through 2015, a span of roughly six years of sales, and later actions covered 3.0-liter diesels as well.
- Claim: The conspiracy produced criminal convictions, not just corporate fines.
  Evidence: All on the legal record. Volkswagen pleaded guilty in 2017 to conspiracy to defraud the United States and its customers and to violate the Clean Air Act, plus obstruction of justice and importing goods by false statements. Engineer James Liang was sentenced to 40 months in prison; executive Oliver Schmidt was sentenced in December 2017 to 84 months and fined 400,000 dollars after pleading guilty. Former chief executive Martin Winterkorn was indicted in the US in May 2018 on conspiracy and wire-fraud charges and remains beyond American jurisdiction.
- Claim: The financial and corporate consequences were vast and are a matter of public record.
  Evidence: Documented across settlements. In the United States alone Volkswagen agreed to civil and criminal resolutions and consumer buybacks together commonly totaled around 25 billion dollars, including the January 2017 settlement of 4.3 billion in criminal and civil penalties. Counting fines and compensation worldwide, the company has reported paying well over 30 billion euros. In May 2025 a German court in Braunschweig convicted four former managers of fraud, sentencing two to prison, nearly a decade after the scandal broke.

## Why people believe it
- The central claim is not a theory but an admission. Volkswagen pleaded guilty in a US federal court and paid billions in penalties, so belief here rests on the company's own confession rather than on suspicion or inference.
- The finding began with independent, replicable measurement. The West Virginia University team, funded by the ICCT, drove the cars on real roads with portable analyzers, and the on-road numbers diverged sharply from the lab, a result that others could and did reproduce.
- Two national regulators reached the same conclusion. The US EPA and California's Air Resources Board investigated jointly, and Volkswagen only conceded the defeat device after CARB threatened to block certification of its next model year, so the admission was pried loose by evidence, not volunteered.
- The courts converted the finding into convictions. Engineers and executives pleaded guilty or were convicted, a former chief executive was indicted, and a German court sentenced managers years later; a scheme that survived that much adversarial scrutiny is as established as a corporate wrongdoing gets.

## Open questions
- How far up the chain of command knowledge of the defeat device actually ran remains contested. Martin Winterkorn denies he knew while the software was in use, his US indictment alleges he was informed by 2014, and his German proceedings were repeatedly delayed and then suspended on health grounds, so a court has not resolved his personal culpability.
- The full public-health toll of the extra nitrogen oxides is hard to pin down. Independent studies have estimated premature deaths attributable to the excess emissions, but such figures are modeled rather than directly counted, and the true cumulative harm cannot be measured precisely.
- How the same illegal approach spread through the wider industry is not fully mapped. Regulators tightened real-world testing afterward and other manufacturers faced their own inquiries, but the extent to which defeat strategies were an industry pattern rather than a Volkswagen aberration is still argued.

## Sources
- Volkswagen Clean Air Act Civil Settlement, U.S. Environmental Protection Agency: https://www.epa.gov/enforcement/volkswagen-clean-air-act-civil-settlement
- Volkswagen AG Agrees to Plead Guilty and Pay $4.3 Billion in Criminal and Civil Penalties; Six Volkswagen Executives and Employees are Indicted in Connection with Conspiracy to Cheat U.S. Emissions Tests, U.S. Department of Justice, Office of Public Affairs (2017): https://www.justice.gov/archives/opa/pr/volkswagen-ag-agrees-plead-guilty-and-pay-43-billion-criminal-and-civil-penalties-six
- Former CEO of Volkswagen AG Charged with Conspiracy and Wire Fraud in Diesel Emissions Scandal, U.S. Department of Justice, Office of Public Affairs (2018): https://www.justice.gov/archives/opa/pr/former-ceo-volkswagen-ag-charged-conspiracy-and-wire-fraud-diesel-emissions-scandal
- EPA's notice of violation of the Clean Air Act to Volkswagen, International Council on Clean Transportation (2015): https://theicct.org/epas-notice-of-violation-of-the-clean-air-act-to-volkswagen-press-statement/
- Volkswagen to Pay Total of $4.3 Billion to Resolve Criminal and Civil Actions, Federal Bureau of Investigation (2017): https://www.fbi.gov/news/stories/volkswagen-to-pay-total-of-43-billion-to-resolve-criminal-and-civil-actions
- Ex-Volkswagen managers convicted over emissions scandal, RTE (2025): https://www.rte.ie/news/business/2025/0526/1515079-volkswagen-emissions/
- How VW Paid $25 Billion for Dieselgate, and Got Off Easy, ProPublica (2019): https://www.propublica.org/article/how-vw-paid-25-billion-for-dieselgate-and-got-off-easy
- Volkswagen emissions scandal, Wikipedia: https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal
- Oliver Schmidt (engineer), Wikipedia: https://en.wikipedia.org/wiki/Oliver_Schmidt_(engineer)

Rated by The Conspiratory, a neutral, sourced encyclopedia of conspiracy theories. Full page: https://theconspiratory.com/theory/volkswagen-dieselgate