This torture of top al-Qaida leaders may also cause problems for the government were there to be a trial for the alleged "dirty bomber" Jose Padilla. The tip that led to Padilla's initial detention on a material witness warrant in May 2002 came from intensive CIA interrogations of Zubaida, a close associate of Osama Bin Laden. In December 2003, the 2nd Circuit Court of Appeals ordered that Padilla be released from military custody and either charged in federal court or released. However, any prosecution of Padilla could be very problematic for the government, because the case for his guilt rests mostly (if not entirely) on secret interrogations of al-Qaida leaders, which now appear to have involved torture. If a criminal case is ever brought against Padilla, his lawyers are sure to challenge this crucial evidence on a number of grounds, including reliability and the fact that it was procured with torture in a way that "shocks the conscience."