Protection of the Hereditary Health of the German nation. This so-
called marriage health law prohibited a marriage if either party
suffered from a mental derangement or had a hereditary disease
specified in the sterilization law. Before marriage, a couple had to
prove that no impediment existed under this law by securing a Marriage
Fitness Certificate from the public health office.An essential prerequisite for the exclusion of minorities was the ability of the state to define and identify members of the groups targeted for persecution. For the disabled, the first step was simple, as the sterilization law listed the disabilities that would define the members of the excluded group. The second step—identification—required greater effort; although it too posed no serious problems, it was never totally successful.
No national register of disabled individuals existed in 1933. Still, the state could use some existing data at the start of the sterilization campaign: lists of persons committed to institutions or attending special schools. But this was not enough, and the authorities had to rely on denunciations. Their number was enormous in the beginning: 388,400 during 1934-1935. Of these, 21 percent were reported by physicians of the public health service, 20 percent by other physicians, and 35 percent by directors of institutions; only 20 percent came from the public. The overwhelming number of denunciations thus came from physicians, nurses, teachers, and social workers. The database on the disabled that was collected as part of the sterilization campaign was augmented by data gathered after passage of the marriage health law. The information thus collected by the public health service grew enormously. The ultimate aim, however, was a comprehensive system of registration to provide eugenic information on all individuals. The state wanted to establish an inventory on race and heredity, which would have enabled the authorities to identify every disabled person and, equally important, their suspect relatives. War and defeat, however, did not permit completion of this task.
The coming of war in 1939 radicalized the exclusionary policies of the Nazi regime. In the winter of 1939–1940, the regime initiated a killing program targeting disabled German nationals, euphemistically labeling this mass murder as "euthanasia," but also designating it "the destruction of life unworthy of life." To implement the decision to kill the disabled, Hitler appointed two plenipotentiaries: Dr. Karl Brandt, his escorting physician, and Philipp Bouhler, who headed the Chancellery of the Führer. The two plenipotentiaries appointed Victor Brack, a senior official of the Chancellery, to organize and direct the killings. Brack created various front organizations designed to hide the involvement of the Chancellery; these were located in Berlin on Tiergarten Street No. 4, and the killing enterprise was therefore known as "Operation T4." But neither the Chancellery, whose participation had to remain secret, nor T4, which masqueraded as a nongovernmental organization, had the power of enforcement. Therefore, the Reich Ministry of Interior, especially its health department, had to serve as enforcer to ensure cooperation. Dr. Herbert Linden, the official in charge of the department dealing with state hospital, race, and heredity, served as the ministry's liaison to the T4 operation.
Hitler labeled the T4 killings as "euthanasia" or "mercy death," although this term did not apply to these killings; the victims did not suffer from a painful terminal condition and could have continued to live painlessly for many years. The scientific and medical community did not oppose Hitler's radical decision to murder the disabled, in part because the idea had circulated since 1920, the year the legal scholar Karl Binding and the psychiatrist Alfred Hoche published a polemic advocating such a radical step with the title "Authorization for