Judge Ronald Thomas began to label Leuchter's methodology as "ridiculous" and "preposterous", dismissing many of the report's conclusions on the basis that they were based on "second-hand information", and refused to allow him to testify on the effect of Zyklon B on humans because he had never worked with the substance, and was neither a toxicologist nor a chemist. Judge Thomas dismissed Leuchter's opinion because it was of "no greater value than that of an ordinary tourist", and in regards to Leuchter's opinion said: