Following the opinion of the Advocate General, the Court of Justice ruled on Thursday, 17 December, that it is illegal to use a device that improves the performance of the gaseous pollutant emission control system during type-approval tests of diesel vehicles (Case C-693/18).
In fact, the court found that the justification that such a device contributes to preventing the engine from ageing or clogging up was not sufficient.
It was responding to a question referred by the Tribunal de...