Fort Carson, Colo. ? The initials were spoken aloud only once all week, and then apparently by mistake.

After this past week’s testimony, any role the CIA had – or didn’t have – in the interrogation of an Iraqi general who died in U.S. custody remains a tantalizing and mysterious backdrop to the court-martial of Army Chief Warrant Officer Lewis Welshofer Jr.

The CIA is “the ghost at the banquet,” said Eugene R. Fidell, an expert in military law who has been following the court-martial but doesn’t know if the CIA was involved in the case.

“We’re playing ‘Hamlet’ without Hamlet here,” said Fidell, a lawyer in private practice who teaches military law at American University in Washington. He also represented news organizations in their attempts to open pretrial hearings in Welshofer’s prosecution.

Welshofer is charged with murder in the 2003 death of Republican Guard Maj. Gen. Abed Hamed Mowhoush at a detention camp in western Iraq.

Prosecutors say Mowhoush was stuffed headfirst in a sleeping bag and bound with electrical cord, then suffocated with Welshofer sitting atop his chest.

The defense contends a heart condition caused Mowhoush’s death, and that Welshofer’s commanders had approved the interrogation technique.

Testimony at Welshofer’s court-martial this past week confirmed that Mowhoush was indeed beaten by Iraqis two days before he died. But the witness, Chief Warrant Officer Todd Sonnek, did not identify the Iraqis.

Then defense attorney Frank Spinner at one point questioned a witness whose identity is so secret that he was shielded from reporters and others by a green tarp suspended from the ceiling. The witness had said he was alarmed when Welshofer told him he thought the Army’s interrogation guidelines were being broken every day.

“And you didn’t report it to the CIA?” Spinner asked. The attorney then stopped himself and quickly apologized to the judge.

Spinner’s apparent slip and the mystery surrounding that witness were not the only indications of how sensitive the case is and how much remains secret.

The two sides presented closing arguments Saturday, and the jury of six Army officers began deliberating.