I disagree with the current top level response here. Yes, there were several documented cases of German soldiers openly taking a stand against Nazi brutality. Typically the “punishment” is that they were either reassigned to less desirable positions or investigated and given (relatively) light slaps on the wrist. But sometimes the punishments were more severe.
- One example is the case of Lieutenant Albert Battel. In 1942, he and his commanding officer Major Max Liedtke were in charge of a Wehrmacht unit in the polish town of Przemyśl. Battel, by that time, was already well known as a “problem” officer because he refused to respect the boundary of Aryan and Untermensch. In the past he had received formal reprimands for such things as shaking hands with a Jew and extending a loan to a Jewish colleague. Anyway, in July 1942 the S.S. informed the German garrison that they were going to launch a “resettlement” operation against the Jews of Przemyśl. Everyone knew what that meant - deportation and mass execution. Battel and Liedke responded by stationing men at the entrance to the Jewish ghetto. When the S.S. unit attempted to cross, they threatened to open fire. The S.S. was forced to temporarily withdraw. Battel took those precious few hours to evacuate about 100 Jews and their families and officially place them under Wehrmacht protection as “essential workers”. However time did run out and the S.S. returned in greater numbers, enough to force the Wehrmacht soldiers to back down. They then proceeded to liquidate all remaining Jewish inhabitants of the ghetto. This event immediately drew attention at the highest ranks of the Nazi government, up to Heinrich Himmler personally. Liedke was reassigned to the Eastern Front and died in Soviet captivity a few years later. Battel seems to have suffered no immediate repercussions, though the S.S. did draw up plans to arrest and prosecute him after the war. He worked a quiet job in a glass factory after the Nazi defeat, and died in 1952 never having been recognized for his risky and heroic actions.
- Another case is that of Viktor Pestek. He was an 18-year-old who was born to a highly nationalist German family, and therefore when war broke out he enlisted in the Waffen-SS. In 1943 he was wounded by partisans during an ambush and hid in a barn only to be discovered by the enemy - but for unknown reasons they spared his life and moved on. This seems to have awakened some of his Catholic faith and his sense of humanity; according to a Jewish witness who spoke to him later, Pestek mused that "I was a killer, and a Soviet partisan spared my life anyway". Because Pestek was wounded and unfit for service at the front, he was offered a reassignment to Auschwitz which he accepted. He was appointed supervisor of section BIId of Auschwitz II-Birkenau. By all accounts of Jews who knew him, Pestek was highly disgusted by the atrocities he witnessed. He is quoted as saying "I hate myself for having to watch women and children be killed. I want to do something to forget the smell of burning human flesh and feel a little cleaner". He also seems to have fallen in love with a female prisoner named Renée Neumann - well, as much as you can "fall in love" in such an artificial and contrived place as Auschwitz. He hatched a convoluted plan designed to help her and her mother escape the camp, a plan that first involved smuggling out another prisoner named Siegfried Lederer. While he did manage to successfully free Lederer, their plot did fail in the end and the S.S. was made aware of what he was trying to do. Lederer was able to escape (and lived to provide witness testimiony on Auschwitz later) but Pestek was arrested, tortured and executed by his former S.S. colleagues.