After studying medicine in Freiburg and Halle, Werner Catel worked at the University Children's Hospital in Leipzig. In 1933, he became its director and, at the same time, was appointed Professor of Neurology and Psychiatry at the University of Leipzig.
In 1938 or 1939, Werner Catel killed a severely disabled child at the request of its parents, after Hitler's accompanying physician Karl Brandt had also examined the child. This case is considered to be the starting point of the »child euthanasia« policy. A year later, Catel set up »children's wards« in Leipzig-Dösen and in the University Children's Hospital in Leipzig. He was an expert on the »Reich Committee«, even killing children with mental or physical disabilities himself.
Catel fled from Leipzig in 1946. The West German authorities de-Nazified him in 1949 and classed him as »Persons Exonerated« (»Entlastete«). After that, he was shortlisted for professorships several times. In 1954, he was appointed Professor of Paediatrics in Kiel, even though his function on the »Reich Committee« was known. Due to public pressure and the debate about his role in National Socialism, Catel took early retirement in 1960. Catel continued to propagate in public the idea of the »euthanasia« of children with mental and physical disabilities.