The witness is the mother of Sylvia Friedman who worked as a nurse for Dr. Clauberg in the notorious Block 10. When Mrs Mouchová came to Auschwitz in 1942 she tried in spite of the warnings to get into Block 10 and succeeded five months later. She shared a room with her daughter and other nurses and lived there for some weeks. During that time she spoke to some of the women on whom experiments and injections with Jodipin had been carried out and witnessed their pains and despair. Most of them seemed mentally deranged. The witness also saw Dr. Clauberg several times who, like Dr. Göbel, always wore civilian clothes, while all the other SS doctors were in uniform.

When Mrs Mouchová discussed with her daughter her iniquitous work, Friedman explained that she was forced to do it, and that all the women would be killed, if she refused. Shortly before the Block was evacuated, Clauberg and Gobel wanted to operate on Friedman, but time ran out.