Jean-Claude Pressac

Jean-Claude Pressac (1944 - July 23, 2003) was a French chemist and pharmacist who became a published authority on the Holocaust of World War II.

Pressac was originally a Holocaust denier who, with Robert Faurisson, attempted to disprove what he considered historically inaccurate depictions of the concentration camps Auschwitz and Birkenau as extermination camps. Upon visiting Auschwitz, however, Pressac was able to view first-hand the extensive archive of construction documents which had survived due to being located in the construction office rather than the administrative offices. These convinced him that his former views were in error, an event he describes in the postface of Auschwitz: Technique and operation of the gas chambers, saying that he "nearly did away with myself one evening in October 1979 in the main camp, the Stammlager, overwhelmed by the evidence and by despair". He published his conclusions along with much of the underlying evidence in his 1989 book, Auschwitz: Technique and operation of the gas chambers . In his 1993 Les Crématoires d'Auschwitz , he further delineated the operation of the crematoria at Auschwitz, and their integration into the larger Nazi program to eradicate the Jews of Europe.