The emissions scandal affecting more than 11 million Volkswagen, Audi and Porsche vehicles around the world likely started in 2005 when engineers initiated a “chain of mistakes” while trying to meet nitrogen-oxide emissions standards in their new line of diesel vehicles, executives for the company said on Thursday. 

Volkswagen chairman Hans-Dieter Potsch said during a press conference in Germany that the company’s engineers introduced the “defeat device” software after realizing there was no legal way for the diesel engines to meet tough U.S. emissions standards “within the required time frame and budget,” The Wall Street Journal reports. 

The device, deemed to be a “sophisticated software algorithm,” is programmed to detect when the car is undergoing official emissions testing, and to only turn on full emissions control systems – the temperature conditioning mode – during that testing.

Potsch said that the device was created at a time when VW saw an opportunity in the market for diesel-powered vehicles in the U.S.

However, the vehicles the company had in mind couldn’t legally fulfill strict emissions standards in the country, and so engineers equipped the cars with software capable of regulating nitrogen-oxide emissions differently depending on how the vehicle was being used.

“There was not one single mistake, but rather a chain of errors that was never broken,” Potsch said.

An internal investigation into the matter has so far determined that the illegal activity went unchecked for so long because the company’s information-technology infrastructure and engine approval procedures were “insufficient” to spot the fraud, the WSJ reports.

Potsch said nine employees had been removed from their positions, although it was unclear if they were guilty of wrongdoing.

“One thing is clear, we are in the middle of the greatest test this company has ever faced,” he said. “You can be certain: These people will be brought to justice.”

An independent investigation by a U.S. law firm could take several more months to complete, the WSJ reports.

Volkswagen Blames ‘Chain of Mistakes’ for Emissions Scandal [The Wall Street Journal]

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