CHICAGO - John Demjanjuk Jr. is convinced that his father will once again be acquitted of charges of murdering thousands of Jews in a Nazi death camp when a German court takes up the case next week.

He is not sure, however, whether his ailing father will survive the high profile trial.

"We know in our hearts that my dad never harmed anyone. And we know based on the evidence that there is absolutely no evidence that he harmed even one person," Demjanjuk Jr. said in a telephone interview.

"The fact is, the case that Germany is putting on was rejected by the state of Israel and the Supreme Court of Israel and it wasn't rejected by a technicality."

John Demjanjuk, 89, tops the Nazi-hunting Simon Wiesenthal Centre's most wanted list and his family has spent much of the past three decades fighting those charges.

He was sentenced to die by an Israeli court in 1988, a decade after Holocaust survivors identified the former Ohio autoworker as the notorious gas chamber operator "Ivan the Terrible."

Five years later that sentence was overturned after statements from former guards identified another man as the sadistic Ukrainian guard.

Demjanjuk was returned to the United States despite strenuous objections from Holocaust survivors and Jewish groups who said he should be retried based on the ample evidence that he was a death camp guard.

The US government filed new charges in 1999 using fresh evidence that surfaced following the collapse of the Soviet Union and he was deported to Germany in May after years of legal wrangling.

The younger Demjanjuk insists that the evidence is far from conclusive and that his father is being pursued for political purposes which have nothing to do with justice.

Decades-old testimony from a former guard who said he saw Demjanjuk lead people to the gas chambers is tainted because of the Soviet history of coercing witnesses, his son insists.

An identification card from Trawniki does not carry the staple holes found on the photograph, lists the wrong height and has a suspect signature, Demjanjuk Jr. said.

"If you want to assume for the sake of argument that they're right and the card is genuine and Demjanjuk was there, there's a mountain of evidence... from various different types of people all congruently testifying that these people were coerced that if a guard tried to escape they were shot," the younger Demjanjuk said.

"We're going to say what is the different between a Ukrainian pow (prisoner of war) who made a choice to live... and the Jewish worker who helped unload the trains, or cut the victim's hair or pulled gold out of the mouths of the dead or cleared bodies out of gas chambers in order to survive."

Demjanjuk also expressed frustration that the German government was pursuing a case against a Ukrainian prisoner of war who was forced to join the German army when so many German death camp guards were never prosecuted.

"It helps them to try to convict a Ukrainian so they can shift the blame," he said, adding that he hopes to find a way to sue the German government.

"There is no giving back the life they've taken from my father," he said.

"They've accelerated his death... he's not going to survive this."

Demjanjuk, who is in custody in a Munich prison, has been given about a year to live and is only fit enough to withstand two trial sessions per day of not more than 90 minutes each, according to medical experts.

The toll has been "devastating," said the younger Demjanjuk, especially given that the family has been unable to get to Germany to visit Demjanjuk and will not be attending the trial.

"He's been dealing with survival his entire life," Demjanjuk Jr. said.

"This started when I was 11 so I don't know much different either. It's about knowing that you're right and fighting for it. That's where we're at."