Oskar Groening, defendant and former Nazi SS officer dubbed the "bookkeeper of Auschwitz", is pictured in the courtroom during his trial in Lueneburg, Germany, July 15, 2015. [Photo/Agencies]

LUENEBURG, Germany - Oskar Groening confessed during his trial to feeling "moral guilt" for serving as an SS sergeant at Auschwitz. On Wednesday, a court ruled that he was guilty of being an accessory to the murder of 300,000 Jews and sentenced him to four years in prison.

The 94-year-old, who testified that he oversaw the collection of prisoners' belongings and ensured valuables and cash were separated to be sent to Berlin, listened expressionlessly to the verdict after a 2 1/2-month trial that could set a legal landmark.

The verdict, and Presiding Judge Franz Kompisch's thorough and impassioned detailing of the Lueneburg state court's ruling, renewed hope of more 11th hour prosecutions of other former members of the SS who served at death camps - no matter their age.

"This verdict was critical, because this is the first case brought where the prosecution charged a person who wasn't involved in the physical side of mass murder," said the Simon Wiesenthal Center's head Nazi hunter, Efraim Zuroff, in a telephone interview from Belgrade.

"This paves the way for additional trials of individuals who did not literally pull the trigger but who were part of the implementation of the Final Solution."

Kompisch acknowledged that Groening was born in a different time, growing up in the aftermath of World War I in Germany in a right-wing nationalist family, in a society where Jews were portrayed as a danger to the country. However, he said Groening joined the SS of his own volition when he had many other options.

"You didn't want to stand on the sidelines," Kompisch told Groening, who listened attentively for more than an hour and a half as the judge detailed the ruling, occasionally sipping from a bottle of water. "You wanted to be there."

In his job at the death camp, for which he has been dubbed the "accountant of Auschwitz," Kompisch said Groening was part of the "machinery of death," helping the camp function and also collecting money stolen from the victims to send to Berlin to help the Nazi cause.

Though he knew exactly what was going on at the camp, he did not have himself transferred away, which likely would have meant serving on the deadly Russian Front, Kompisch said.

"It is a question of courage and a personal decision," he said. "You decided on a job where the possibility of your own death was relatively minimal."

"What you, Mr. Groening, see as moral guilt is exactly what the law sees as accessory to murder," the judge said.

Groening walked out of the courtroom without talking to reporters.