In September, Pfc. Andrew Holmes, of Boise, Idaho pled guilty to the unpremeditated murder of the first victim, as well as to drug use and to keeping a finger bone from the victim as a souvenir. Holmes had also posed for a photo, later leaked to the media, in which he held up the head of the dead victim.
Holmes, 21, admitted to the judge that he had fired his machine gun at the victim, that he knew the man was probably innocent , and that he believed he had caused the man's death.
Spc. Adam Winfield, who warned his parents that soldiers in his unit were executing innocent Afghan civilians, pled guilty in August to reduced charges and was sentenced to three years in prison for his role in the third killing, which took place in May 2010. He had been charged with premeditated murder, which carries a sentence of life in prison without parole.
Both Morlock and Winfield are expected to testify against Gibbs. Both have told Army investigators that Gibbs developed and rehearsed the murder of unarmed Afghans and later ordered his men to help him carry them out.
Spc. Michael S. Wagnon II, who is still awaiting trial, has pled not guilty. Wagnon is charged with participating in a cover-up of the second killing, which occurred in February 2010, as well as conspiracy and possessing a human skull fragment.
Lawyers for Gibbs and Wagnon have previously assailed Morlock's testimony against their clients, noting he requested investigative documents prior to testimony.
In addition to murder, the Army's charging documents allege rampant drug use in Morlock's unit, as well as the dismemberment of dead Afghan civilians.
Cpl. Morlock described in the Army investigators' video how Sergeant Gibbs allegedly collected the fingers of some of his Afghan victims.
"It's his thing now," said Morlock. "I don't know, his crazy stuff. War trophies, whatever."
Morlock said Gibbs boasted of carrying out similar murders in Iraq but was never caught and threatened the men in his unit with harm if they refused to participate or revealed what was happening.
"If Gibbs knew that I was sitting in front of this camera right now, there's no doubt in my mind that he'd f---ing take me out if he had to," Morlock told the Army investigators.