Germany’s highest court, the Federal Constitutional Court in Karlsruhe, announced Friday that it will not hear the appeal of the 15-year sentence of convicted September 11 conspirator Mounir al-Motassadeq. Moroccan-born Motassadeq has another appeal to German appellate courts filed, but it is unknown when it will be considered. Lawyers for Motassadeq have also said they may take the case to the European Court of Justice.

Motassadeq admitted to attending an al-Qaeda training camp in Afghanistan and being friends with some of the Sept. 11 hijackers, but denies knowledge of the attack. The court found Motassadeq guilty because he knew his accomplices planned to hijack planes, even if he remained ignorant as to the details of the attacks. The court also found that Motassadeq aided the hijackers by funneling money and helping them maintain appearances of being university students. Motassadeq's defense team hoped to force a new trial with witnesses previously prevented from testifying by the United States government. Motassadeq's first conviction was overturned in 2004, in part due to concerns over access to witnesses, but on retrial American officials refused to allow terror suspects in US custody to testify in court, instead agreeing only to provide summaries of its interrogations of prisoners.