High Court showdown: Mercedes, Ford and Renault stand accused in Dieselgate trial
Car manufacturing giants, including Mercedes, Ford and Renault, are set to face a lengthy trial at the High Court over allegations they cheated emissions tests.
Knicknamed Dieselgate, the largest group claim ever brought in the UK, is set to kick off at the court on Monday morning for a 10-week trial in front of Lady Justice Cockerill.
The case is over a range of diesel vehicles sold by Mercedes, Ford, Renault, Nissan, and Peugeot/Citroen from 2009 that contained technology designed to cheat official emissions tests.
The carmakers are accused of seeking to hide the levels of toxic nitric oxide and nitrogen dioxide (NOx) emissions coming out of their diesel cars to pass regulatory tests.
The vehicle owners claim that software, known as ‘cheat devices’ or ‘prohibited defeat devices (PDDs)’, was installed within the engine management systems, which could detect when the cars were under test conditions and, for those periods, ensure harmful emissions were kept within legal limits.
However, when the vehicles were driven on the road, it is claimed they produced much higher levels of emissions such as nitrogen oxides and particulates, which pollute the environment and cause a higher risk to people’s health.
It has been over 10 years since the scandal erupted over Volkswagen diesel emissions, which revealed the manufacturers had used “defeat devices” to cheat on emissions tests.
As a result of the scandal, Volkswagen faced several fines, legal settlements, and buyback programmes, which have been estimated to be over $32bn (£24.1bn), including a $2.8bn criminal penalty to the US Environmental Protection Agency (EPA). Volkswagen AG owns the Porsche, Audi, SEAT, and Lamborghini car brands.
The manufacturer faced fines in Germany, the US and the European Union, but the British government has yet to punish any car company for this scandal.
Volkswagen paid £193m in 2022
This isn’t the first legal action in England over this issue. Volkswagen agreed to pay £193m in an out-of-court settlement in May 2022 to more than 90,000 drivers in England and Wales.
But now, a mammoth case has been brought by 22 law firms, with Leigh Day leading, on behalf of 1.6m vehicle owners in England and Wales against Mercedes, Ford, Renault, Nissan, and Peugeot/Citroen.
In addition, there have been claims made against Vauxhall/Opel, Volkswagen/Porsche, Jaguar Land Rover, BMW, FCA/Suzuki, Volvo, Hyundai-Kia, Toyota, and Mazda.
The main trial is expected to conclude before Christmas, with legal submissions regarding the evidence due to be heard in March 2026. The judgment is expected to be delivered in the Summer of 2026.
Leigh Day’s senior partner, Martyn Day, said: “A decade after the Dieselgate scandal first came to light, 1.6m UK motorists now get their chance to establish at trial whether their vehicles contained technology designed to cheat emissions tests.”
A Nissan spokesperson said, “Nissan is committed to compliance in all markets in which we operate. Emissions testing regimes and standards have evolved considerably over time and continue to do so to improve air quality and reduce emissions. Nissan is fully supportive of these changes.”
A spokesperson for Mercedes said, “We believe that the claims are without merit and will vigorously defend ourselves against them or any group action with the necessary legal means.
In our opinion, the emission control software functionalities in question are justifiable from a technical and legal standpoint.”
Ford, Renault, and Peugeot/Citroen, owned by Stellantis, were also contacted for comments.