While the Holocaust is often placed at the genesis of bioethics, this relatively young field has not yet seriously explored the conduct of German scientists and physicians involved in the human subjects experiments of the Holocaust. We comfort ourselves with the beliefs that the individuals involved in the events of the Holocaust were mad or evil and unlike other scientists and physicians. Yet the evidence is that these professionals were educated and capable members of a technologically sophisticated society who believed they were somehow behaving morally within the context of their social-political situation. The first defendants at Nuremberg were physicians and public health officials. An examination of the trial transcripts provides data about what motivated these medical scientists to engage in human experimentation and mass murder and the extent to which ethics rationales were given for unparalleled moral wrong-doing in biomedicine. Bioethics must still address these beliefs and subject them to close scrutiny.