NEW YORK -- Sulaiman Abu Ghaith, the most senior adviser to Osama bin Laden to be tried in a civilian U.S. court since the Sept. 11 attacks, was convicted Wednesday of conspiring to kill Americans and providing material support to terrorists.
Mr. Abu Ghaith, a 48-year-old Kuwaiti-born cleric known for his fiery oratory, had recorded impassioned speeches for bin Laden after Sept. 11, in which he praised the attacks and promised that future attacks would be carried out.
His conviction on all three counts -- and the lightning speed from his arrest to verdict -- would seem to serve as a rejoinder to critics of the Obama administration's efforts to try suspected terrorists in civilian court, rather than before a military tribunal.
"It was appropriate that this defendant, who publicly rejoiced over the attacks on the World Trade Center, faced trial in the shadow of where those buildings once stood," U.S. Attorney General Eric H. Holder Jr. said in a statement. "This outcome vindicates the government's approach to securing convictions against not only this particular defendant, but also other senior leaders of al-Qaida."
The jury returned its verdict on its second day of deliberations in the trial, which had entered its third week in U.S. District Court in Manhattan. Mr. Abu Ghaith was convicted of conspiracy to kill Americans, for which he could face life in prison; and providing material support to terrorists, as well as conspiring to do so, counts that each carry maximum terms of 15 years.
Mr. Abu Ghaith was asked to rise as the judge's deputy clerk, Andrew Mohan, read the verdict aloud, and the defendant appeared impassive as the word "guilty" was repeated three times.
His lawyer, Stanley L. Cohen, said later that his client was stoic and "at ease."
"He has confidence that this is not the end but the beginning," Mr. Cohen said. The lawyer added that there were "a number of compelling issues" for appeal.
Mr. Abu Ghaith, who is married to bin Laden's daughter Fatima, was captured last year and brought to the United States on terrorism charges. His lawyers sought to portray their client as having had a minimal role in al-Qaida, with no involvement or advance knowledge of any terrorist plot, planned or executed.
The defendant unexpectedly took the witness stand last week, offering a vivid account of being summoned by bin Laden on the night of the attacks to meet with him in his cave in the Afghan mountains.
"He said, 'Come in, sit down.' He said, 'Did you learn about what happened?'?" Mr. Abu Ghaith recalled the al-Qaida leader telling him.
Mr. Abu Ghaith said bin Laden claimed credit for the attacks and told him the next day that he wanted Mr. Abu Ghaith to help him "deliver a message to the world."
Mr. Cohen, in a closing argument Monday, said his client had not always been speaking on behalf of al-Qaida, and was rather fulfilling his responsibility as an imam.
"You saw videos from a theologian," Mr. Cohen said. "These words and these concepts may be offensive to you. They may disgust you. But you are going to have to decide the context."
But the prosecution repeatedly reminded the jury, often through photographs and videos, of how close Mr. Abu Ghaith had been to bin Laden, who was then the most wanted man on the planet.
The prosecution, for example, showed the jury a video screen shot of Mr. Abu Ghaith, made on Sept. 12, 2001, as he sat beside bin Laden and two other al-Qaida leaders, including Ayman al-Zawahri, the Egyptian-born current leader of al-Qaida.
"Sulaiman Abu Ghaith literally sat at Osama bin Laden's right hand," a prosecutor, John P. Cronan, said in his closing argument.
He cited one video, made on Oct. 9, 2001, in which Mr. Abu Ghaith warned that "the storm of airplanes will not abate," and that there were thousands of Muslim youths who were yearning for death, "just as the Americans yearn to live."
That message, Mr. Cronan said, was meant to terrorize Americans, but also "to drive more suicide terrorists to al-Qaida."
Preet Bharara, the U.S. attorney for the Southern District of New York, said in a statement: "Like the others who have faced terrorism charges in Manhattan's federal courthouse before him, Abu Ghaith received a fair trial, after which a unanimous jury rendered its verdict, justly holding him accountable for his crimes.
"We hope this verdict brings some small measure of comfort to the families of the victims of al-Qaida's murderous designs," Mr. Bharara added.