Germany's highest court begins hearing the appeal of Mounir el Motassadeq Thursday. The court will determine whether the 32-year-old Moroccan knew enough about the plans of the Sept. 11 hijackers to be considered the member of a terrorist group.

Motassadeq lives in Hamburg and was part of a circle that included Mohamed Atta and two of the other hijackers that carried out the suicide attacks in the US. Motassadeq's lawyers argue he was a low-tier member of a group of radical Arab students and did not know the hijackers' plans.

Long court process

In 2003, a court in the northern city of Hamburg determined that Motassadeq had plotted holy war with fellow Muslim extremists. Motassadeq was sentenced to 15 years in jail for the murder of more than 3,000 people in the attacks in New York and Washington, making him the first person convicted for his alleged role in the attacks.

But the verdict was overturned in March 2004 because US authorities had refused to allow questioning of top al Qaeda suspects held in American custody.

A retrial found no evidence that Motassadeq had been directly involved in planning the attacks, but he was still sentenced to seven years in jail for belonging to a terrorist organization. In a surprise move, Germany's constitutional court released Motassadeq from prison in February pending his appeal.

A friend of terrorists

Motassadeq's defense team believes they can prove that while Motassadeq was a friend of the terrorists, he himself was not a member of a terrorist organization.

"We believe we can convince the court that the decision was unjust and should be overturned," said Motassadeq's lawyer Ladislav Anisic.

A decision by Germany's highest court of appeals is likely to take several weeks and will focus on complicated legal questions. Motassadeq will not appear, preferring to await the decision at home in Hamburg with his wife and two children, Anisic said.