Leuchter report

The Leuchter report is a pseudoscientific document authored by American execution technician Fred A. Leuchter, who was commissioned by Ernst Zündel to defend him at his trial in Canada for distributing false news, namely Holocaust denial material. Leuchter compiled the report in 1988 with the intention of investigating the feasibility of mass homicidal gassings at Nazi extermination camps, specifically at Auschwitz. He travelled to the camp, collected multiple pieces of brick from the remains of the crematoria and gas chambers (without the camp's permission), brought them back to the United States, and submitted them for chemical analysis. At the trial, Leuchter was required to defend the report in his capacity as expert witness; however he was dismissed because during the proceedings it became apparent that he had neither the qualifications nor experience to act in such a position.

Leuchter chiefly cited the absence of Prussian blue in the homicidal gas chambers in support of his view that they could not have functioned that way. However, residual iron-based cyanide compounds are not a categorical consequence of cyanide exposure. By not discriminating against that, Leuchter introduced an unreliable factor into his experiment, and the outcome was seriously flawed as a result. In contrast, scientifically respectable tests conducted by Polish forensic scientists (who discriminated against iron-based compounds) confirmed the presence of cyanide in the locations and manner in accordance with where and how it was used in the Holocaust. In addition, the report also showed that Leuchter overlooked critical evidence, such as documents in the SS architectural office which directly contradicted him, indicating the mechanical operation of the gas chambers, and verifying the rate at which the Nazis could burn the bodies of those gassed.

In 1985, Ernst Zündel, a German pamphleteer and publisher living in Canada, was put on trial for publishing Richard Verrall's Holocaust denial pamphlet Did Six Million Really Die?, which was deemed to violate Canadian laws against distributing false news. Zündel was found guilty, but the conviction was overturned on appeal. This led to a second prosecution.

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