Joint Base Lewis-McChord, Washington (CNN) -- Staff Sgt. Calvin Gibbs is a world away from the tiny, sun-baked Afghan villages he is accused of terrorizing as the leader of what prosecutors call a rogue group of soldiers that targeted civilians.
But on Thursday, in a drafty military courtroom near Tacoma, Washington, Gibbs is expected to learn if he will spend the rest of his life in prison for those killings.
Gibbs is the highest-ranking of five soldiers accused of murdering Afghan villagers, planting weapons on them and cutting body parts off to keep as grisly war trophies. Seven other soldiers were also charged with lesser crimes such as intimidating a fellow soldier not to speak out against the platoon's alleged killings and rampant illegal drug use.
Gibbs has pleaded not guilty. On Wednesday, the defense and prosecution rested, giving Gibbs' case to a five-person panel composed of three officers and two enlisted soldiers who will decide whether the staff sergeant walks free or serves a potential life sentence.
"Sergeant Gibbs had a charisma, he had a 'follow me' personality," Maj. Robert Stelle, a prosecutor in the case, told the court in closing arguments Wednesday. "But it was all a bunch of crap, he had his own mission: murder and depravity."
"No one died before Sergeant Gibbs showed up," Stelle said.
Gibbs took over the 3rd Platoon of the Army's 5th Stryker Brigade in November 2009 in Kandahar Province, Afghanistan. The platoon's previous sergeant had been badly injured by a roadside bomb attack.
Prosecutors described the clean-cut and tall Gibbs as looking like he walked off a "recruiting poster." But the staff sergeant also sported six skull tattoos on his left shin signifying his "kills," prosecutors said, quoted Darwin and referred to Afghan civilians as "savages."
According to soldiers who testified at the court-martial, Gibbs discussed what he called "scenarios," or staging firefights so the soldiers could kill civilians and make it look as if they were Taliban fighters.
"It's not about killing. It's about selling that kill to the command, making them believe it's legitimate," Stelle said.
Those "scenarios," prosecutors said, became reality over a period of five months when the soldiers allegedly plotted to execute civilians. The soldiers killed three villagers in separate incidents, prosecutors said.
Gibbs is charged with murder in all three slayings. Prosecutors said he supplied an "off the books" grenade in one alleged murder and in the other two killings personally executed the villagers. In all three incidents, prosecutors claimed, the soldiers lied about first being attacked before firing their weapons.
Phillip Stackhouse, Gibbs' defense attorney, said other soldiers are framing his client. Three soldiers have pleaded guilty to the killings and have agreed to testify against Gibbs as part of plea deals reached with prosecutors.
"What if there is no hard evidence other than what you have heard from that witness stand?" Stackhouse said Wednesday. Some witnesses also admitted to smoking hashish they obtained from Afghan translators. Their testimony, Stackhouse said, "came under a cloud of hash."
Stackhouse argued Gibbs wasn't where other witnesses said he was during the engagements. And according to Stackhouse, in February 2010 Gibbs couldn't have smuggled an AK-47 in his backpack into a village where prosecutors claim he then planted the assault rifle on an Afghan man he had killed. Grasping an AK-47, Stackhouse showed the rifle would not fully fit into a soldier's backpack.
Prosecutors countered that Gibbs had used a different model of the rifle that has a shorter muzzle and could be concealed.
"It's not this, 'If it doesn't fit you must acquit.' It does fit!" prosecutor Stelle told the court, referencing the well-known moment in the O.J. Simpson trial in which Simpson was unable to fit his hands into gloves used in the slaying of his ex-wife.
During his daylong testimony on Friday, Gibbs denied murdering civilians. But Gibbs did admit to cutting off body parts from Afghans he said were killed in legitimate engagements.
"I compared it to keeping antlers off a deer I shot," Gibbs said, explaining why he cut fingers from the hand of a man he shot and killed.
That shooting and finger-severing took place on a mission meant to build support with the local population. Prosecutors said the man was murdered. Gibbs said he fired in self-defense after the man shot at him first.
"That was the finger he tried to kill me with; I was pretty pissed off about it," Gibbs said.
But prosecutors said the idea that a lone Taliban carrying a rifle with one clip of ammunition would charge a heavily armed patrol of U.S. soldiers was preposterous.
"This guy, a high-ranking Taliban -- Sergeant Gibbs wants you to believe -- decides to take on a dismounted platoon with no more ammunition, no backup," Stelle said. "It's fundamentally implausible."
Panel deliberations are scheduled to begin at 9:30 a.m. Thursday.