Five carmakers go on trial over emissions cheat claims

A major trial against five leading automakers accused of cheating on emissions tests is set to begin in the Supreme Court on Monday.

The hearing is the latest chapter in what is known as the “diesel cap” scandal, in which companies face allegations they used software that allows their vehicles to reduce emissions of harmful gases under test conditions.

Lawyers say the case is the largest class action in English and Welsh legal history and could eventually involve 1.6 million car owners.

All five automakers (Mercedes, Ford, Peugeot/Citroën, Renault and Nissan) deny the accusations.

These five people were selected by the court as the primary defendants to be tried first due to the huge nature of the case.

Mercedes, Ford, Peugeot/Citroën, Renault and Nissan are accused by 220,000 car owners of misleading them about emissions tests.

However, depending on the outcome of this case, nine more automakers will face similar claims.

The Dieselgate scandal first emerged in September 2015, when the US Environmental Protection Agency accused Volkswagen of installing software known as “defeat devices” in diesel cars to reduce the cars’ nitrogen oxide emissions.

In 2020, the Supreme Court ruled that Volkswagen used defeat devices to beat emissions tests, in breach of European Union rules.

Volkswagen settles class-action lawsuit out of courtIt pays £193 million to 91,000 British drivers.

The company has so far paid out more than €32bn (£27.8bn) as a result of the scandal, most of it in the US.

The Supreme Court will decide whether the systems installed in diesel cars by five automakers were designed to violate clean air laws.

“Defeat devices” are claimed to allow a car to detect when it is in a test scenario. He would then run his engine below normal power and performance levels to register lower nitrogen oxide readings.

Lawyers for the drivers will argue that they were misled about how environmentally friendly the vehicles were and that the vehicles still on the road continue to emit dangerous levels of pollution.

Although the trial begins on Monday, a decision is not expected until summer 2026. If the court rules against the automakers, a new trial to determine compensation levels is expected to begin in the fall of 2026.

Martin Deigh, of Leigh Day, one of 22 law firms representing drivers, said: “Ten years after the Dieselgate scandal first emerged, 1.6 million British motorists now have the chance to determine at trial whether their vehicles contain technology designed to cheat emissions tests.”

He said if the allegations against the car companies were upheld in court it would “represent one of the most egregious breaches of corporate trust in modern times”.

“This could also mean that people in the UK are breathing in far more harmful emissions from these vehicles than they are told, potentially putting the health of millions more at risk.”

The companies involved said the allegations against them were unfounded.

A spokesman for Mercedes said the mechanisms used in the tests were “technically and legally justified”.

Renault and Stellantis, which own Peugeot and Citroen, said that the vehicles they sold complied with the regulations at that time.

Ford said the allegations “have no merit”, while Nissan said it was “committed to complying with the rules in all markets in which we operate”.