Certain initial aspects of Nazi persecution of Jews and other opponents were common knowledge in Germany. Thus, for example, everyone knew about the Boycott of April 1, 1933, the Laws of April, and the Nuremberg Laws, because they were fully publicized. Moreover, offenders were often publicly punished and shamed. The same holds true for subsequent anti-Jewish measures. Kristallnacht (The Night of the Broken Glass) was a public pogrom, carried out in full view of the entire population. While information on the concentration camps was not publicized, a great deal of information was available to the German public, and the treatment of the inmates was generally known, although exact details were not easily obtained.
As for the implementation of the "Final Solution" and the murder of other undesirable elements, the situation was different. The Nazis attempted to keep the murders a secret and, therefore, took precautionary measures to ensure that they would not be publicized. Their efforts, however, were only partially successful. Thus, for example, public protests by various clergymen led to the halt of their euthanasia program in August of 1941. These protests were obviously the result of the fact that many persons were aware that the Nazis were killing the mentally ill in special institutions.
As far as the Jews were concerned, it was common knowledge in Germany that they had disappeared after having been sent to the East. It was not exactly clear to large segments of the German population what had happened to them. On the other hand, there were thousands upon thousands of Germans who participated in and/or witnessed the implementation of the "Final Solution" either as members of the SS, the Einsatzgruppen, death camp or concentration camp guards, police in occupied Europe, or with the Wehrmacht.