Julius Viel, now a retired journalist, sat stony-faced as the presiding judge read out the verdict in Ravensburg district court, saying he acted "out of lust for murder and base motives" and not on orders.
Viel, a second lieutenant in the SS at the time of the crimes, has denied the prosecution charges that he shot the inmates at Theresienstadt in Nazi-occupied Czechoslovakia in the spring of 1945.
"I'm sorry for my wife's sake," Viel told journalists afterwards. His attorney said Tuesday he would appeal, citing contradictory evidence.
Prosecutors had sought a life sentence for Viel, one of Germany's last Nazi war crimes suspects likely to face justice. The court cited the long interval between the crimes and the trial in imposing the lower sentence.
However Winkler said Viel's exemplary life after the war did not reduce the enormity of his original crime.
"At the beginning of this life's journey, there were seven deaths," he noted. "The killing of a human was a crime then as well. The defendant knows it wasn't animals but people he did away with."
Viel was already investigated for the slayings in the 1960s, but the case was closed for lack of evidence. He became a respected journalist in West Germany after the war and was awarded a government medal for his writings on hiking.
But German prosecutors recently reopened the case after a new statement by Adalbert Lallier, a one-time Nazi officer trainee who says he witnessed the killings. Viel was arrested in October 1999 and went on trial in December.
In seeking acquittal, Viel's lawyers sought to cast doubt on Lallier's reliability as a witness.
Lallier, an economics professor in Canada, testified at the trial that a group from the SS officers' school watched over the inmates as they dug a tank trap against advancing Soviet forces in Theresienstadt.
Standing guard as the prisoners toiled, Lallier said he saw Viel seize a rifle and shoot the victims in cold blood
Lallier, who was born in Hungary and now lives in Quebec, first told his story publicly in 1998. He said he had stayed silent for so long out of loyalty to his fellow soldiers, but was persuaded to speak out by another former SS officer.
"Lallier certainly did not imagine what happened," Judge Winkler said Tuesday.
Proceedings are underway in Canada to consider whether Lallier should have his citizenship withdrawn because of his own membership in the SS, the black-uniformed elite corps of the Nazi Party.
But Viel's defense attorney, Ingo Pfliegner, announced he would appeal the verdict. He complained that the ruling contained a "multitude of contradictions."
The SS, short for Schutzstaffel, was the dreaded quasi-military unit of the Nazi arty, which was used as a special police force and committed some of the worst crimes in territory under Nazi control during World War II.
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