The mood in the Congress Hall of the Braunschweig town hall was relaxed: there was laughter and giggling, the man in the robe spoke to the older gentleman in the middle of the hall. Sometimes it was reminiscent of conversations with one’s own grandfather, who amused the listeners with his dry manner. What sounds like a comedic chamber play was nothing less than the interrogation of one of the most important witnesses to perhaps one of Germany’s greatest economic crimes.

In the past two days, ex-VW boss Martin Winterkorn testified in the investor trial against Volkswagen AG – and ridiculed the German constitutional state with its defense strategy. Because it looked like this: Whenever Judge Christian Jäde asked witness Winterkorn whether he had ever seen or heard of any of the dozens of pieces of evidence – emails, notes, recordings – for his knowledge of the manipulation of exhaust emissions in diesel vehicles, Winterkorn answered : “Mr. Chairman, this is the first time I have seen this letter.” In an American sitcom there would be a burst of laughter at this point. The reaction in a German courtroom: disarmed silence from the public prosecutor.

The problem: The jurisprudence has no remedy against the three magic words of a witness or defendant: “I don’t remember.” In the Winterkorn case, the first acts of the diesel scandal were more than 20 years ago. At the same time: As early as 2007, there were supposed to be indications that VW was “cheating” with its emissions values, as one could trivialize. In fact, according to the Braunschweig public prosecutor’s office, the emissions scandal caused damage worth 78 billion euros.

Criminal proceedings are still ongoing against Martin Winterkorn, including for alleged fraud and false statements. He is innocent until proven guilty. But: The US judiciary has issued an international arrest warrant against him and the Braunschweig judges see “sufficient suspicion” – and therefore an “overwhelming probability of conviction” for the ex-manager for “commercial and gang-related fraud”. Winterkorn was able to avoid scrutiny of these allegations for health reasons. The doctors appointed by the court confirmed this – his hip problems did not stop Winterkorn from visiting the FC Bayern stadium.

When Judge Jäde confronts him with quotes from his ex-colleagues, which suggest that Winterkorn knew about illegal practices in VW diesel early on, he takes the opportunity to discredit them. Bernd Gottweis, then head of the product safety committee at Volkswagen, warned Winterkorn in May 2014 that “dramatic” increases in emissions from VW diesel engines had been noticed in the USA. His former boss says today: “Gottweis was an important man for me, but he was someone who always saw the glass as half empty. He took on things that he had no idea about.”

At the end of the second day of interrogation, Winterkorn shows that he can still be rough – and is by no means a frail senior. The plaintiff’s lawyers cross-examine him and the ex-manager, who answered calmly and politely most of the time, suddenly becomes a pit bull. He gestures, his face seems to turn reddish. When he limps out of the hall around 4 p.m. – his hip is apparently still causing him problems – the sympathy of most of the aggrieved shareholders was probably rather limited.

This article first appeared on “Capital”, which, like stern, is part of RTL Deutschland.