A 93-year-old former guard at Auschwitz said his work at the concentration camp made him "morally complicit" in the atrocities committed there, but he told judges at the opening of his trial they "must decide on the question of ... criminal liability."

Oskar Groening, who has been dubbed the "Accountant of Auschwitz," is charged with 300,000 counts of accessory to murder at the camp during World War II. But, as Deutsche Welle, the German broadcaster, reports, the case is unique because Groening isn't accused of actually killing anyone. The prosecution's case, instead, rests on 300,000 Hungarian Jews killed at Auschwitz in 1944 and on the argument that anyone who served as a guard at a Nazi camp was complicit in what happened there.

The German broadcaster adds:

"Groening has been open about the fact that he worked at Auschwitz during the war, and although he admitted that he was ashamed of his role, saying he was 'a cog in the killing machine,' he maintains that he never personally committed any atrocities."The former member of the Nazi Waffen-SS worked at Auschwitz in occupied Poland at the age of 21. His nickname, the 'bookkeeper,' came from the fact that he was responsible for counting the banknotes gathered from prisoners' luggage and passing them on to the SS authorities in Berlin."When he was charged in the northern German city of Hanover last year, prosecutors said Groening also helped remove victims' luggage to prevent it from being seen by new arrivals — thereby hiding the traces of the Nazi mass killing."

Prosecutor Jens Lehmann read out the indictment today against Groening, saying: "Through his job, the defendant supported the machinery of death."

Groening, in his opening statement to the court in Lueneburg, Germany, said: "I recognize this moral guilt here as well, with remorse and humility in front of the victims."

But, he added: "You must decide on the question of my criminal liability."

Among those present in the courtroom were Holocaust survivors.

If found guilty, the 93-year-old could face a maximum sentence of 15 years in prison.

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