Khalid Sheikh Mohammed, 9/11 Co-Conspirators to Go to Military Commission Trial

The alleged mastermind of the Sept. 11, 2001, terror attacks on the U.S. will be referred to the Defense Department for trial, three sources familiar with the case told Fox News on Monday.

Khalid Sheikh Mohammed, who has been incarcerated in Guantanamo Bay, Cuba, since 2006, after being captured in Pakistan in 2003, and five alleged Sept. 11 co-conspirators will face prosecution by a military commission in Guantanamo, a Justice Department official said.

A formal announcement is expected by Attorney General Eric Holder later in the day. The decision is a turn-around after Holder said in November 2009 that he had decided the conspirators -- Mohammed, Walid Muhammed Salih Mubarak Bin Attash, Ramzi Bin Al Shibh, Ali Abdul-Aziz Ali and Mustafa Ahmed Al Hawsawi -- should be prosecuted in civilian court.

At the time, President Obama said he left the decision to Holder. White House Press Secretary Jay Carney said Monday that the decision to reverse himself remained with Holder, but he didn't want to get ahead of the announcement.

"The president's primary concern here is that the perpetrators ... of that terrible attack on the American people be brought to justice as swiftly as possible and as fairly as possible," he said.

Debra Burlingame, head of 9/11 Families for a Safe and Strong America, said the group is "relieved" Obama "abandoned his plan" to bring the conspirators to U.S. soil.

"We are grateful to the president for reversing his decision, conveyed to the families just last month, to go forward with civilian trials and seek repeal of congressional legislation that stripped funding for that effort," said Burlingame, whose brother was the pilot aboard American Airlines Flight 77, which was forced into the Pentagon on Sept. 11.

"We have great confidence in the military commissions legal framework which is fair, lawful, effective and consistent with our tradition and values as a nation," she said. 

Shortly after the Obama administration came to office, the president announced that he was closing Guantanamo Bay and desired to try the conspirators in a federal civilian court. Supporters said it sent the right message to the rest of the world that U.S. courts were the fairest and best venue for trials.

But attempts to place the suspects in a New York City courtroom were met with fierce resistance from area residents who said they didn't want to deal with another possible terror threat in downtown Manhattan that the case would bring. The potential of housing the suspects in a prison in Thomson, Ill., also faced considerable scrutiny.

J.D. Gordon, a former Defense Department spokesman for secretaries Donald Rumsfeld and Robert Gates, said Mohammad and the other co-conspirators were already going through the military commission process before the Obama administration halted the case. He said the administration must have realized that popular opinion was against using civilian courtrooms in the United States.

"I think they ran into the buzz saw of reality where the American public didn't see it in their best interest to hold Khalid Sheikh Mohammed in a civilian trial where he could theoretically be acquitted there and also where he'd have a chance to have his rhetoric used against us," Gordon said.

"I think that to trust the civilian jury with some of the most dangerous terror suspects is really a flawed mistake," Gordon added.

With the case now returning to the military commission, the process will start all over again. After the administration announced in 2009 it planned to move the trials to federal court, the military withdrew its charges without prejudice -- an action that effectively allowed it to preserve its legal position so that if the cases returned to the commissions in the future, the men could be charged again.

As the Justice Department prepared to announce its reversal, the U.S. Supreme Court on Monday also decided to pass on a case that would have further determined the legal rights of the detainees kept at Guantanamo Bay.

The justices turned away a petition asking them to establish the standards of evidence lower court judges should use to determine if the detainees can remain locked up while waiting for their cases to be heard.