A federal judge ruled Monday that prosecutors can use a confession by a man charged with joining al-Qaida and plotting to assassinate President George W. Bush, despite defense claims that the confession was obtained through torture by Saudi security forces. US District Judge Gerald Bruce Lee said he would explain his rationale in a forthcoming order. The ruling came after a six-day hearing in which Ahmed Omar Abu Ali testified that Saudi interrogators whipped him on his back, kicked him in the stomach and pulled on his beard to obtain a confession. In the confession, Abu Ali said he joined al-Qaida because he hated the United States for its support of Israel. He said he discussed numerous potential plots with his al-Qaida cell members, including assassinating Bush, conducting a September 11-style attack using planes hijacked from outside the United States, establishing an al-Qaida cell inside the US and freeing Muslim prisoners held at the US Navy base in Guantanamo Bay, Cuba.