A French newspaper reports that Renault has cheated emissions testing for up to 25 years and that boss Carlos Ghosn was likely aware of the cheating.

Local publication Liberation, cited by Reuters, says that Renault used a device similar to those used by Volkswagen to allow its vehicles to meet nitrogen oxide (NOx) pollution regulations and says that the Captur and Mk4 Clip polluted 300 per cent higher in real-world conditions than their test results suggested.

The report referenced by Liberation, published by French consumer protection agency DGCCRF in November, says that Ghosn as well as other top executives were likely aware of the wrongdoing.

The agency says that the “entire chain of command” should be held responsible but that Ghosn should be held directly accountable as “no delegation of powers had been established by Carlos Ghosn regarding the approval of engine control strategies.”

Renault, as with a number of other automakers, claims that the devices it used were legal as they were necessary for engine protection and safety.

In a statement regarding this latest report, Renault said it “will not comment on a current investigation, the latter being confidential by nature and Renault having as yet no access to the case. As a consequence, Renault cannot confirm the veracity, completeness and reliability of the information published in [the] article.”

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