Bizarre self-taught "professional engineer" of execution
methods. He became a professional execution consultant and did consulting work on various US states' death chambers.
He later wrote a controversial holocaust denying
report in 1988 for Ernst Zundel
that stated Zyklon B
was not used to kill humans. His findings were discredited because Leuchter made many factual errors (indeed, he had no formal training in engineering
but instead obtained a BA in history in 1964). Nizkor.org
thoroughly discredited the Leuchter Report
Leuchter was the subject of the 1999 Errol Morris
documentary: "Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr.".