Air Force Staff Sgt. Luis Walker arrives for the fourth day of his trial at Lackland Air Force Base in San Antonio, Texas on July 20, 2012. (Billy Calzada,AP Photo/San Antonio Express News)
(AP) SAN ANTONIO - A Texas Air Force instructor accused in a broad military sex abuse scandal posted as a "wolf in sheep's clothing" to prey on already scared trainees, a prosecutor said Friday in her closing argument.
Staff Sgt. Luis Walker's trial is expected to go to a jury Friday after three days of testimony. He is charged with 28 counts including rape and aggravated sexual assault involving at least 10 women in basic training.
Walker's trial is seen as the cornerstone of a major investigation into trainers at Lackland Air Force Base in San Antonio, where every American airman receives basic training. Six instructors have been charged on counts ranging from rape to adultery. Walker is the first to stand trial.
Maj. Patricia Gruen said trainees arrived at Lackland "terrified" of their instructor, and Walker used that fear to take advantage of them.
"He is the wolf in sheep's clothing. Consummate predator," Gruen said.
He took his victims to hallways and other areas where surveillance cameras would not catch him, she said.
Trainers like Walker "rule their worlds," Gruen said. "They get off that bus and, bam! Their world is changed."
Gruen took just less than an hour for her closing argument. Walker's defense is expected to present its closing argument later Friday.
A six-man, one-woman jury of military personnel will decide the case. Prosecutors called 14 witnesses, including one alleged victim who gave a video deposition because she had recently given birth and could not travel to the base.
On Tuesday, one alleged victim fought back tears as she testified that Walker lured her into his office and sexually assaulted her on a bed, ignoring her pleas for him to stop. She and others told jurors they were afraid that reporting Walker's actions would get them kicked out of the Air Force.
The Associated Press typically doesn't identify alleged sexual assault victims.
The defense called just one witness, Tech. Sgt. Richard Capestro, who testified that instructors and trainees at the Lackland base are under constant surveillance and officials conduct surprise inspections of trainee dormitory areas without warning - seemingly attempting to cast doubt on the possibility Walker could have committed rape and sexual assault on the premises.
Capestro said there are cameras in the hallways and at least some of the stairwells around base dormitories, and that open microphones allow an official on duty in a control room to push a button and listen in on any activity in the dorms.
Lackland has about 475 instructors for the approximately 35,000 airmen who graduate every year. About one in five is female, pushed through eight weeks of basic training by a group of instructors, 90 percent of whom are men.
Once the case goes to the jury, under Air Force court rules, its members consider every charge and can reach a guilty verdict on each with a simple two-thirds majority vote.
If Walker is found guilty on any charge, sentencing begins immediately and is also decided by the jury.
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