[7] In October 1939, Adolf Hitler signed a "euthanasia note", backdated to 1 September 1939, which authorised his physician Karl Brandt and Reichsleiter Philipp Bouhler to begin the killing.

[10] The Holy See announced on 2 December 1940 that the policy was contrary to divine law and that "the direct killing of an innocent person because of mental or physical defects is not allowed" but the declaration was not upheld by all Catholic authorities in Germany.

[20][21] In July 1933, the "Law for the Prevention of Hereditarily Diseased Offspring" prescribed compulsory sterilisation for people with conditions thought to be hereditary, such as schizophrenia, epilepsy, Huntington's chorea and "imbecility".

If we do nothing but make mental and physical cripples capable of propagating themselves, and the healthy stocks have to limit the number of their children because so much has to be done for the maintenance of others, if natural selection is generally suppressed, then unless we will get new measures our race must rapidly deteriorate.

[25][26][27]Within the Nazi administration, the idea of including in the programme people with physical disabilities had to be expressed carefully, because the Reich Minister of Propaganda, Joseph Goebbels, had a deformed right leg.

[41] After the invasion of Poland, Hermann Pfannmüller (Head of the State Hospital near Munich) said It is unbearable to me that the flower of our youth must lose their lives at the front, so that that feeble-minded and asocial element can have a secure existence in the asylum.

The National Socialist Racial and Political Office (NSRPA) produced leaflets, posters and short films to be shown in cinemas, pointing out to Germans the cost of maintaining asylums for the incurably ill and insane.

These films included The Inheritance (Das Erbe, 1935), The Victim of the Past (Opfer der Vergangenheit, 1937), which was given a major première in Berlin and was shown in all German cinemas, and I Accuse (Ich klage an, 1941) which was based on a novel by Hellmuth Unger, a consultant for "child euthanasia".

Those to be killed were identified as "all children under three years of age in whom any of the following 'serious hereditary diseases' were 'suspected': idiocy and Down syndrome (especially when associated with blindness and deafness); microcephaly; hydrocephaly; malformations of all kinds, especially of limbs, head, and spinal column; and paralysis, including spastic conditions".

[40][h] The last child to be killed under Aktion T4 was Richard Jenne on 29 May 1945, in the children's ward of the Kaufbeuren-Irsee state hospital in Bavaria, Germany, more than three weeks after US Army troops had occupied the town.

After the invasion on 1 September 1939, adults with disabilities were shot by the SS men of Einsatzkommando 16, Selbstschutz and EK-Einmann under the command of SS-Sturmbannführer Rudolf Tröger, overseen by Reinhard Heydrich, during Operation Tannenberg.

[67] The first experiments with the gassing of patients were conducted in October 1939 at Fort VII in Posen (occupied Poznań), where hundreds of prisoners were killed by means of carbon monoxide poisoning, in an improvised gas chamber developed by Albert Widmann, chief chemist of the German Criminal Police (Kripo).

[70][j] Reich Leader Bouhler and Dr. Brandt are entrusted with the responsibility of extending the authority of physicians, to be designated by name, so that patients who, after a most critical diagnosis, on the basis of human judgment [menschlichem Ermessen], are considered incurable, can be granted mercy death [Gnadentod].The killings were administered by Viktor Brack and his staff from Tiergartenstraße 4, disguised as the "Charitable Foundation for Cure and Institutional Care" offices which served as the front and was supervised by Bouhler and Brandt.

Three "death" verdicts condemned the person and as with reviews of children, the process became less rigorous, the range of conditions considered "unsustainable" grew broader and zealous Nazis further down the chain of command increasingly made decisions on their own initiative.

[80] Once the efficacy of the method was confirmed, it became standard and was instituted at a number of centres in Germany under the supervision of Widmann, Becker and Christian Wirth – a Kripo officer who later played a prominent role in the Final Solution (extermination of Jews) as commandant of newly built death camps in occupied Poland.

[l] In 1971, Gitta Sereny conducted interviews with Stangl, who was in prison in Düsseldorf, having been convicted of co-responsibility for killing 900,000 people, while commandant of the Sobibor and Treblinka extermination camps in Poland.

He was given three gas vans by the Reich Security Main Office (RSHA), converted by the Gaubschat GmbH in Berlin[92] and before February 1942, killed 3,830 Polish Jews and around 4,000 Romani, under the guise of "resettlement".

[94][m] The first killing centre, equipped with stationary gas chambers, modelled on technology developed under Aktion T4, was established at Bełżec in the General Government territory of occupied Poland; the decision preceded the Wannsee Conference of January 1942 by three months.

[95] In January 1939, Brack commissioned a paper from Professor of Moral Theology at the University of Paderborn, Joseph Mayer, on the likely reactions of the churches in the event of a state euthanasia programme being instituted.

[96] Some bureaucrats opposed the T4 programme; Lothar Kreyssig, a district judge and member of the Confessing Church, wrote to Justice Minister Franz Gürtner protesting that the action was illegal since no law or formal decree from Hitler had authorised it.

The SD report on the incident at Absberg noted that "the removal of residents from the Ottilien Home has caused a great deal of unpleasantness" and described large crowds of Catholic townspeople, among them Party members, protesting against the action.

[100] Similar petitions and protests occurred throughout Austria as rumours spread of mass killings at the Hartheim Euthanasia Centre and of mysterious deaths at the children's clinic, Am Spiegelgrund in Vienna.

Anna Wödl, a nurse and mother of a child with a disability, vehemently petitioned to Hermann Linden at the Reich Ministry of the Interior in Berlin to prevent her son, Alfred, from being transferred from Gugging, where he lived and which also became a euthanasia center.

[102] Bishop Theophil Wurm, presiding over the Evangelical-Lutheran Church in Württemberg, wrote to Interior Minister Frick in March 1940 and that month a confidential report from the Sicherheitsdienst (SD) in Austria, warned that the killing programme must be implemented with stealth "...to avoid a probable backlash of public opinion during the war".

[104] Bishop Heinrich Wienken of Berlin, a leading member of the Caritas Association, was selected by the Fulda episcopal synod to represent the views of the Catholic Church in meetings with T4 operatives.

In 2008, Michael Burleigh wrote Wienken seems to have gone partially native in the sense that he gradually abandoned an absolute stance based on the Fifth Commandment in favour of winning limited concessions regarding the restriction of killing to 'complete idiots', access to the sacraments and the exclusion of ill Roman Catholic priests from these policies.

[105]Despite a decree issued by the Vatican on 2 December 1940 stating that the T4 policy was "against natural and positive Divine law" and that "The direct killing of an innocent person because of mental or physical defects is not allowed", the Catholic Church hierarchy in Germany decided to take no further action.

[111][109] In 1986, Lifton wrote, "Nazi leaders faced the prospect of either having to imprison prominent, highly admired clergymen and other protesters – a course with consequences in terms of adverse public reaction they greatly feared – or else end the programme".

[113] Burleigh called assumptions that the sermon affected Hitler's decision to suspend the T4 programme "wishful thinking" and noted that the various Church hierarchies did not complain after the transfer of T4 personnel to Aktion Reinhard.

Between September 1939 and April 1945 the defendants Karl Brandt, Blome, Brack, and Hoven unlawfully, wilfully, and knowingly committed crimes against humanity, as defined by Article II of Control Council Law No.