The shadow of Dieselgate returns as French court summons Europe’s car giants
A decade after the emissions scandal first shook the automotive world, Europe’s largest manufacturers are once again heading to court. French prosecutors have concluded a long running investigation and ordered Volkswagen, Renault and Stellantis to stand trial in Paris over alleged manipulation of nitrogen oxide emissions.
The move signals renewed determination within the European legal system to pursue what prosecutors describe as systematic consumer deception. It also lands at a delicate moment, as the industry pours billions into electrification while still paying for the sins of the diesel era.
Defeat devices under scrutiny
The investigation centres on so called defeat devices, software designed to detect laboratory emissions tests and temporarily activate full exhaust treatment systems. Outside controlled conditions, in normal road use, some vehicles allegedly emitted up to 40 times the permitted level of nitrogen oxides.
French prosecutors argue that this amounted not only to regulatory evasion but to consumer fraud, with direct consequences for public health and environmental protection.
For Volkswagen, the case reopens old wounds. The group has already spent more than 30 billion euros globally on fines, compensation and settlements linked to the original Dieselgate scandal. The French trial, expected to begin in 2027, could add billions more, particularly in light of earlier European Court rulings that strengthened consumer protection claims.
Renault’s position differs in tone but not in gravity. The company has consistently denied deliberate software manipulation. However, independent road tests found that certain models, including the Renault Kangoo, produced real world emissions many times above official limits. As part of the investigation, Renault deposited 20 million euros in bail and provided a 60 million euro bank guarantee to cover potential damages.
Stellantis, which oversees brands such as Peugeot, Citroën and Fiat, faces allegations concerning Euro 6 diesel engines. The group maintains that its systems complied with regulations in force at the time of production. French investigators have nonetheless questioned whether internal controls and compliance processes were sufficient.
Strategic strain in the electric era
The timing is awkward. While Tesla and BYD expand aggressively across Europe, established manufacturers must divert capital to legal defence and potential settlements.
Volkswagen and Stellantis now face a strategic choice. Prolonged litigation risks further reputational damage and financial drain. A negotiated settlement could limit uncertainty but at a high upfront cost. Every euro spent on legacy diesel liabilities is a euro not invested in battery development, software platforms or next generation electric models.
Analysts note that diesel’s market share in Europe has fallen to a record low of around 8 percent. Yet consumer confidence in the technology has not entirely evaporated, particularly among drivers who value range and fuel efficiency.
The French proceedings will not resurrect the diesel boom years. They do, however, remind the industry that the transition to electric mobility does not erase past accountability. Even as manufacturers promote zero emission futures, courts continue to examine the emissions of yesterday.
