Osama bin Laden's son-in-law was convicted in New York on Wednesday of conspiring to kill Americans by serving as Al-Qaeda's spokesman after the attacks of Sept. 11, 2001.
The verdict was returned for Sulaiman Abu Ghaith in federal court in Manhattan. The 48-year-old Kuwaiti clergyman could face life in prison when he is sentenced Sept. 8 on charges of conspiracy and aiding Al-Qaeda.
"This verdict is a major milestone in the government's unrelenting efforts to pursue justice against those involved with the Sept. 11 attacks," U.S. Attorney General Eric Holder said in a statement.
Preet Bharara, U.S. attorney for the Southern District of New York, said he hoped the verdict brought some measure of comfort to Al-Qaeda victims.
"He was more than just Osama bin Laden's propaganda minister," Bharara said in a statement. "Within hours after the devastating 9/11 attacks, Abu Ghaith was using his position in Al-Qaeda's homicidal hierarchy to persuade others to pledge themselves to Al-Qaeda in the cause of murdering more Americans."
On Monday, during closing arguments of Abu Ghaith’s three-week trial, Assistant U.S. Attorney John Cronan underscored the importance of the defendant’s post-9/11 status.
"During the most important period of time in Al-Qaeda's savage history, Sulaiman Abu Ghaith was Osama bin Laden's principal messenger ... He used his fiery oratory to incite Al-Qaeda's growing army of terror in this war with America," he said.
Taking the witness stand in his own defense, Abu Ghaith calmly denied he was an Al-Qaeda recruiter and claimed his role was a religious one aimed at encouraging all Muslims to rise up against their oppressors. He insisted that he agreed to meet with bin Laden in a cave on the night of Sept. 11, 2001, only out of respect.
Defense attorney Stanley Cohen emerged from court on Wednesday promising to appeal.
Cohen complained outside court after the verdict that U.S. District Judge Lewis A. Kaplan rushed the verdict by warning jurors at the start of deliberations Wednesday that he might direct them to stay late if they were not finished by 4:30 p.m.
Cohen said the judge's instruction sent a message to the jury: "You should be done. This is a no-brainer."
"It's terribly coercive," the lawyer said.
Cohen said an appeal would partially stem from the judge's decisions barring testimony about Abu Ghaith’s lengthy confinement in Iran and rejecting the defense’s request to call self-described 9/11 mastermind Khalid Sheikh Mohammed as a witness. In a written statement, Mohammed had said Abu Ghaith had no military role in Al-Qaeda.
"I think he feels it was impossible under the circumstances to receive a fair trial, given certain rulings," Cohen said of his client.
Abu Ghaith was captured in Jordan last year and brought to New York for trial. He is the highest-ranking Al-Qaeda figure to face trial on U.S. soil since the attacks.
U.S. prosecutors alleged that he was bin Laden's right-hand man and, as the group’s main messenger after the 9/11 attacks, inspired a new generation of individuals seeking to hurt Americans.
Defense lawyers said Abu Ghaith knew nothing about conspiracies. He testified that bin Laden asked him the night of the attacks to be Al-Qaeda's spokesman.
Videos showing Abu Ghaith threatening the U.S. with no end to the "storm of airplanes" were shown to jurors.
The outcome of the trial will be closely watched as pressure builds on the White House to close the Guantánamo Bay prison camp, and is seen by some as proof that detainees can face civil justice.
Attorney General Holder said Wednesday, "I want to especially note that this verdict has proven that proceedings such as these can safely occur in the city I am proud to call home, as in other locations across our great nation."
Al Jazeera and wire services