John Demjanjuk: Convicted Nazi guard who protested his innocence for three decades

Rarely was there a greater outward contrast between an accused and the terrible crimes of which he was found guilty. For friends, he was a doting grandfather, a retired Ukrainian immigrant who had worked in the US car industry and tended his surburban lawn outside Cleveland, Ohio. But for a German law court, and the Nazi-hunters who pursued John Demjanjuk for three decades, he was part of the machinery of genocide at Hitler's death camps.

Demjanjuk's conviction in Munich in May 2011, of being accessory to the murder of 28,060 people at the Sobibor camp in Nazi-occupied Poland during 1943, may prove the last major war crimes case brought to justice – and perhaps the last of its kind handled by the Office of Special Investigations, the unit of the US Justice Department set up to pursue suspected Nazi war criminals living in America.

In fact, Demjanjuk was tried not once, but twice. As a result of the OSI's efforts, he was first stripped of his US citizenship in 1981, and extradited to Israel in 1986 for the first war crimes trial there since Adolf Eichmann was prosecuted in 1961. He was accused of being "Ivan the Terrible," a sadistic guard who ran the gas chambers at the Treblinka extermination camp where at least 800,000 were killed. After a 17-month trial, he was convicted and sentenced to death.

However new evidence emerged suggesting that "Ivan the Terrible" was in fact another Ukrainian named Ivan Marchenko, and in July 1993 – even as the gallows to hang him were being built – Demjanjuk was acquitted by the Israeli Supreme Court, because of doubts about his presence at Treblinka. But the ruling contained a fateful paragraph: "The facts proved the appellant's participation in the extermination process," the Court declared. "The matter is closed, but not complete." And so it proved. A final judgement had not been delivered, merely deferred.

John Demjanjuk was born in Ukraine in 1920, but moved with his family to Moscow as a child to escape the Ukraine's terrible famines of 1932 and 1933. After joining the Soviet youth organisation Komsomol, he was drafted into the Soviet Union and sent to the Ukrainian front when Hitler invaded the Soviet Army in 1941. The following year he was wounded, taken prisoner and sent to a Nazi forced labour camp.

At war's end, he spent seven years in a displaced persons' camp where he met and married his wife, and started a family. In 1952 the Demjanjuks emigrated to the US where he became a naturalised citizen, changing his name to John and working at Ford plants in Indiana and then Ohio. But in 1977 his legal troubles began when the US immigration authorities accused him of lying on his citizenship application papers, and concealing his service at Nazi camps.

From then on, the case of John Demjanjuk revolved around one issue: what precisely happened to him between his capture by the Germans in 1942, and the final stages of the war when he appears to have joined the shortlived Russian Liberation Army of the defected Red Army general Andrei Vlasov, whose aim was to defeat the Soviet Union and restore independence to Ukraine.

In Demjanjuk's telling, he spent the time as a prisoner at forced-labour camps in Poland and Germany. In fact, according to prosecutors, citing documents from Nazi and Soviet archives, he was trained as a guard and worked, if not at Treblinka, then at the camps of Majdanek, Sobibor and Flossenburg during 1943 and 1944.

After his acquittal in Israel, Demjanjuk returned to the US where his citizenship was restored in 1998. But almost immediately his problems restarted, amid the new evidence of his involvement with the camps. In 2002 he again lost his citizenship, and was ordered to be deported to Germany, Poland or Ukraine. Finally, after a long legal battle in the US, Germany issued an arrest warrant against him for war crimes, and on 30 November 2009 the 89-year-old Demjanjuk was brought into a Munich courtroom in a wheelchair to answer charges he had been accessory in the deaths of 28,060 while he was a guard at Sobibor.

The case was remarkable by any standards. He was the first person found guilty solely on the basis of serving as a camp guard, with no evidence that he was involved in a specific killing. There were no eyewitnesses (Nazi death camps were not in the business of leaving survivors); Demjanjuk was not a German and his crime did not take place on German soil. For many, the case was less about an individual than about Germany's need to show that 65 years on, it had not forgotten its past.

Nonetheless he was convicted, essentially on the basis of an SS identity card indicating Demjanjuk had been assigned to Sobibor. The defence challenged the card's authenticity, noting that even the FBI suspected it was a Soviet forgery. But expert witnesses said it appeared genuine. "The court is convinced that the defendant served as a guard at Sobibor from March 27, 1943, until mid-September 1943," presiding Judge Ralph Alt ruled. The evidence, he said, showed Demjanjuk was a piece of the Nazis' "machinery of destruction," and that he knew full well what the purpose of the camp was.

On 12 May, 2011, Demjanjuk was sentenced to five years in jail but was released pending appeal. He died in a nursing home while awaiting the hearing. To the end he insisted that he was innocent, a victim of mistaken identity. "I couldn't even kill a chicken," he told the Israeli court back in 1987, "my wife had to do it."

Ivan Mykolayevych Demjanjuk, convicted Nazi war criminal. Born Dubovye Makharintsy, Ukraine, 3 April, 1920. Married Vera Bulochnik (one son, two daughters). Died Bad Feilnbach, Germany, 17 March, 2012