LONDON (Reuters) – A crucial trial targeting several of the world’s biggest carmakers begins in Britain’s High Court on Monday, with lawyers representing 1.6 million plaintiffs accusing the manufacturers of cheating on diesel emissions tests, ten years after the Volkswagen “dieselgate” scandal.

In one of the largest class actions in English legal history, owners of diesel vehicles made by Mercedes-Benz, Ford, Nissan, Renault and the Stellantis Group’s Peugeot and Citroën brands allege that the companies used illegal “defeat devices”.

According to the plaintiffs’ lawyers, these devices detected faulty vehicles and ensured that emissions remained within legal limits during testing, but did not work when the cars were being driven.

The manufacturers, however, say the complaints are fundamentally wrong and reject any similarity with the “dieselgate” scandal which broke out in 2015 and which cost Volkswagen billions of euros in fines and compensation.

Mercedes-Benz said its emissions control systems were legally and technically justified.

TRIAL ON “DEVALIATION DEVICES” STARTS

The trial will focus on a small sample of diesel vehicles produced by the five manufacturers, which are being sued by nearly 850,000 plaintiffs, to determine whether they used banned defeat devices.

What damages the court could order to be paid will be decided at another trial next year.

The London High Court’s ruling will also be binding on hundreds of thousands of similar claims filed against other manufacturers, including Vauxhall/Opel, owned by Stellantis, and BMW.

Martyn Day, one of the plaintiffs’ lawyers from law firm Leigh Day, said the allegations, if proven, would “demonstrate one of the most egregious violations of business trust in modern times.”

For “dieselgate”, when VW admitted to using defeat devices during emissions tests, the automaker had to pay more than 32 billion euros in vehicle overhauls, fines and legal costs. Former CEO Martin Winterkorn has meanwhile faced criminal charges, although his trial was suspended this month for health reasons.

DISPUTES AND FINES AROUND THE WORLD

This is not the first time that the High Court in London has been called upon to rule on defeat devices, having ruled against VW in 2020. VW settled these claims without admitting liability in 2022.

This time around, the class action against 14 manufacturers in total is much larger than the VW case, with the plaintiffs’ lawyers having previously valued the entire dispute at around 6 billion pounds (6.89 billion euros).

Automakers have recently faced lawsuits around the world, including in the Netherlands, where a court ruled in July that diesel cars sold by Stellantis’ Opel, Peugeot-Citroën and DS brands included defeat devices, a ruling Stellantis called wrong.

Manufacturers and suppliers have also paid fines and reached settlements in the United States and elsewhere to resolve investigations into diesel vehicle emissions.

(Sam Tobin; Coralie Lamarque, edited by Augustin Turpin)

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