 Zündel was originally found guilty by two juries but was finally acquitted upon appeal by the Supreme Court of Canada which held in 1992 that section 181 (formerly known as section 177) was a violation of the guarantee of freedom of expression under the Canadian Charter of Rights and Freedoms.The 1988 trial relied on testimony from Holocaust deniers David Irving and Fred A. Leuchter, a self-taught execution technician.Leuchter's testimony as an expert witness was accepted by the court, but his accompanying Leuchter report was excluded, based on his lack of engineering credentials.