And here starts the push for surely "rogue engineers" are responsible, please don't extradite the executive team:

   Mr. Winterkorn, who has denied knowledge of the illegal software, also had a 
   reputation for dealing harshly with subordinates who failed to meet their 
   targets.

So if we believe their spin, it was a see no evil deal: the ceo had his hands clamped firmly over his ears telling engineers to make an engine work or be fired, and make sure not to tell him the details of what they had to do.

That push started quite a while ago. And there is a good chance that it started even before the news broke in the media.