Reply #1: In case anyone would wonder why they think he should be prosecuted:

[Judi Lynn]

Concentration camp doctor Aribert Heim is the most-wanted Nazi war criminal
By Ben Martin
Last Updated: 10:14PM BST 30/04/2008

A doctor accused of murdering hundreds of Jewish prisoners at Mauthausen concentration camp has been named as the world's most-wanted Nazi war criminal.

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According to the 1950 testimony of Karl Lotter, a non-Jewish political prisoner who worked alongside Heim in the camp hospital, the doctor killed an 18-year-old Jew with a minor foot injury.

Instead of treating the teenager, Heim cut him open, castrated him and removed some of his organs, before removing his head, which was put on display.

"He needed the head because of its perfect teeth," said Mr Lotter in his testimony. "Of all the camp doctors in Mauthausen, Dr Heim was the most horrible."

Witnesses have told investigators that Heim also worked closely with Erich Wasicky, an SS pharmacist, who conducted experiments such as injecting different solutions into the hearts of Jewish prisoners to see which killed them the fastest.

But while Wasicky was tried and sentenced to death by an American military tribunal in 1946, Heim, who was also in American custody, evaded prosecution because his file had apparently been altered to remove records of his presence at Mauthausen. He later fled, leaving a German court to convict him in absentia of more than 100 counts of murder in 1979.

More:
http://www.telegraph.co.uk/news/worldnews/1915505/Concentration-camp-doctor-Aribert-Heim-is-the-most-wanted-Nazi-war-criminal.html