Former Volkswagen Group chief executive Martin Winterkorn denied responsibility for the diesel emissions scandal in court testimony on Wednesday, more eight years after revelations of the affair rocked the German auto giant. Winterkorn, 76, took the witness stand in a civil lawsuit brought by VW investors. Winterkorn is also facing two criminal proceedings over his alleged involvement in the scandal, in which VW diesel engines were programmed to appear cleaner in emissions testing than in real-w