During the hearing, Papp acknowledged systematically doping under the guidance of medical professionals in the United States, Europe and Latin America. He admitted to using EPO, human growth hormone, cortisone, insulin, thyroid hormone, anabolic steroids and amphetamines. The testimony, while not fundamental to the arbitration panel's decision to uphold Landis's conviction, elicited a hostile response. In an interview published in VeloNews, Landis asked interviewer Neal Rogers, "Why did they bring in Joe Papp? Who the f--k is that guy?" During the period he was testifying in the Landis case Papp was actively trafficking EPO and HGH.