A documents cache seen by the Guardian show that the commission’s in-house science service told it in 2010 that tests had uncovered what researchers suspected to be a “defeat device” that could cheat emissions tests.

VW was caught by US authorities last year using defeat device software that detected if a car was being driven under lab test conditions, and adjusted itself to reduce emissions of harmful nitrogen oxide (NOx) pollution. Under real world conditions, the 11m VW cars affected had higher NOx emissions.

The director of the EU’s enterprise department claimed in April that the commission’s science service, the Joint Research Centre (JRC), had failed in previous reports to flag up the risk of such defeat devices.

But a report sent from the research centre to the directorate as far back as 2010 warned that its testing had found potential cheating by a car-maker.

“One vehicle tested showed extremely high NOx emissions during the low temperature type 6 test,” it said. “Since NOx emissions at low temperature are currently not regulated, this observation hints towards a very peculiar combustion strategy (defeat strategy?) the manufacturer applies at low temperature.”

The device kicked in immediately after the “light off” of the catalytic converters and involved an “artificially lean combustion strategy reducing HC/CO (high hydrocarbon/CO2 output) but increasing NOx emissions”.

It is not known which car maker was involved in the suspected test cheat but experts told the Guardian that the description bore the hallmarks of a “thermal window” defeat device, software used by numerous car manufacturers.

According to the campaign group Transport and Environment, the programme turns off the cars’ exhaust after-treatment systems at outside temperatures of about 17C. It has only recently been discovered and is already highly contested.

JRC scientists told the European parliament’s ‘dieselgate’ inquiry that they were never given a mandate to investigate the defeat devices issue further.

But a note from the EU’s environment department (DG Envi) in 2010 said that work on “defeat strategies” was “an important concern” for them.

In 2013, an air pollution study by the department warned of: “Increasing evidence of illegal practices [by car manufacturers] that defeat the anti-pollution systems to improve driving performance or save on the replacement of costly components.”

As such, the documents trawl, obtained by the Dutch environmental magazines Down to Earth and OneWorld and shared with the Guardian, casts serious doubt on the European commission’s competence in handling the issue.

Kathleen van Brempt, the chair of the dieselgate inquiry, said that the papers were “shocking” and raised questions about the future of commission officials.

“These documents show that there has been an astonishing collective blindness to the defeat device issue in the European commission, as well as in other EU institutions,” she told the Guardian.

Seb Dance, the inquiry’s coordinator, said that they “completely contradict everything the commission has told us up to now about their having had no evidence of defeat strategies being used by car manufacturers.”

In April, Daniel Calleja Crespo, the director of the EU’s enterprise department, told the dieselgate inquiry that, despite being aware that vehicles’ real-world NOx emissions were much higher than in test conditions, the commission “did not see there was cheating going on”.

But in November 2014, a year before the VW scandal, he had received a plea from DG Envi’s then-director, Karl Falkenberg, for a response to his calls for an EU probe into defeat devices.

“We continue to believe that DG Enterprise should investigate the regularity – and, if confirmed, demand corrective action – of certain current practices [in which] certain manufacturers deploy emission abatement techniques that are switched off at low temperatures or when the vehicle needs additional power,” Falkenberg said.

“This practice in our opinion goes beyond what is allowed by the Euro 5/6 [emissions test] legislation,” he wrote in the letter. “A request to look into this matter more deeply has remained unanswered so far.”

Crespo did not answer it in his response. He said: “Regarding the application of different strategies during the type-approval test and in real driving conditions, such practices are illegal in accordance to the European law and any manufacturer applying them would face severe legal consequences.”

VW has yet to face any legal consequences for its use of defeat devices in Europe, despite ongoing proceedings in the US. In Europe, legal actions are a matter for nation states.

But experts say that the commission had the power and, arguably, a responsibility to alert member states to the defeat devices issue. It could also have informed its legal services department and contacted car manufacturers to ask whether their cars were causing a serious environmental problem that necessitated their recall.

One letter released in the trawl, from the Dutch environment minister to the EU’s industry commissioner in September 2015, says: “We would like you to consider the possibilities of a European recall … to ensure that all faulty software is removed from the market and replaced by proper software that allows proper emissions reduction.”

“The commission should have alerted the member states’ national supervisors,” van Brempt said. “Although it is not obliged, those states could have taken cars off the road, tested them and enforced the legislation.”

Crespo did not respond to questions sent by the Guardian. In a twist to the tale, he displaced Falkenberg last September, and is now the bloc’s most powerful environment officer, after Karmenu Vella, the EU’s commissioner for the environment.

A commission spokesperson said that the bloc had known about the risk of defeat devices in 2014, but “was not aware of any actual instances of fraud. We were just as shocked as everyone about the revelations of the Volkswagen emissions manipulation.”

The official added that it was common knowledge that lab tests did not reflect real-world NOx emissions, which were up to 20 times higher, but that this could have been due to many factors. “No concrete evidence on the use of defeat devices or of the failure of a member state to act was ever brought to the attention of the commission,” she said.

However, another EU source was less sanguine. “The commission’s position in this has been one of trying to avoid any responsibility,” one told the Guardian.

“Legally, the responsibility for enforcement of the legislation rests with member states. Whether the commission did enough to alert those states and ensure that they were carrying out their responsibilities is a very pertinent question.”

Arthur Neslen

This article first appeared on the Guardian

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