Rare Letter Sent and Signed in 1935 by SS Dr. Leonardo Conti Designer of the Nazi T4 Euthanasia Programme. Letter deals with some doctors and mental institutions. Leonardo Conti (24 August 1900 – 6 October 1945) was the Reich Health Leader and an SS-Obergruppenführer in Nazi Germany. He was involved in the planning and execution of Action T4 that murdered hundreds of thousands of adults and children with severe mental and physical handicaps.
Conti was a staunch promoter of a public medical administration strongly controlled by the Nazi state. Under his leadership, local health offices were further expanded to allow for genetic control and selection of the population in order to remove "weak" elements for the improvement of the German race, a doctrine known as eugenics. The various programmes were the basis for "racial hygiene" a lethal part of the Nazi philosophy. Conti worked with Dr. Karl Brandt to draft plans for the extermination of all Germany's mental patients along with those suffering from severe physical handicaps. This program, known euphemistically as Action T4, is estimated to have killed over 200,000 adults and children between 1939 and 1945. Conti was initially placed in charge of this initiative but soon was replaced by Philip Bouhler.

Accordingly, he was co-responsible for the forced sterilization program, the racially motivated forced pregnancy interruptions, and ultimately the Action T4 euthanasia program. It is also undisputed that Conti participated in human experiments.Conti was also involved in the forensic investigation into the Katyn massacre, and received a detailed report, known as the Katyn Commission on the discovery from an international team of experts.
On 19 May 1945, after Germany's surrender, Conti was imprisoned and in October hanged himself to avoid Nuremberg Doctor's Trials.