A decade after Volkswagen’s emissions scandal exploded onto the world stage, the saga returns to the spotlight in the UK. This time, it is not just one automaker under fire but a multitude: more than a dozen global car brands are accused of using defeat devices to cheat emissions tests on millions of diesel vehicles sold from 2009 onward. The case has become the largest class action in English legal history, as 1.6 million motorists seek damages believed to total at least £6 billion.
The trial, which began this week at London’s High Court, will initially focus on Mercedes-Benz, Ford, Nissan, Renault, and Stellantis-owned Peugeot and Citroen. Plaintiffs claim these carmakers installed software that detected official emissions testing and temporarily lowered pollutants just long enough to pass, before reverting to higher-polluting settings in day-to-day driving. The lawyers contend car owners were misled about how environmentally friendly these models were, pointing out that many continue to emit dangerous levels of pollution while on the road.
Carmakers are vigorously rejecting the allegations, claiming there is no equivalence to the original Volkswagen scandal. They argue that their emission management systems were both legal and technically justified for protecting engines not for cheating the rules. None have been fined or penalized in the UK on the same scale as Volkswagen, which paid over £30 billion globally and settled UK claims for £193 million with 91,000 drivers in 2022.
At stake is more than compensation. If the High Court finds for the claimants, a second trial next year will decide what payout, if any, aggrieved drivers can expect. Industry observers say the case could expand to involve up to 14 car brands and nearly 2 million drivers if successful. Lead lawyer Martyn Day describes the trial as a test of “one of the most egregious breaches of corporate trust in modern times,” warning that millions may have been exposed to air pollution far above what they were promised.
This is a new chapter in the global push for greater transparency and accountability over vehicle emissions. As other manufacturers, including BMW and Stellantis’s Vauxhall/Opel, face similar lawsuits, the UK trial’s outcome is set to influence regulatory standards, marketing claims, and consumer rights well beyond Britain’s borders.
A verdict is expected by summer 2026, with any damages or further firestorms following late that year. The world’s automakers and drivers will be watching as dieselgate unfolds.
