Last Updated 5:25 p.m. ET
(CBS/AP) SAN ANTONIO - An instructor at an Air Force base in San Antonio is facing rape and sexual assault charges at court-martial, the first to stand trial in a sex scandal implicating a dozen people that has rocked one of the busiest military training centers.
Staff Sgt. Luis Walker faces up to life in prison and a dishonorable discharge if convicted.
Walker is among 12 instructors at Lackland Air Force Base who are being investigated in the scandal. Walker faces the most serious charges. He is charged with 28 counts, including rape, aggravated sexual contact and multiple counts of aggravated sexual assault.
Procedural issues were discussed Monday morning and opening statements are expected Monday afternoon.
Walker's father and two other family members were in the courtroom at the base.
Military officials say the initial flirtations that Walker directed at the women he trained became something more sinister: threats and intimidation that led to sex and eventually rape.
The 10 female recruits Walker is accused of either sexually assaulting or engaging in inappropriate sexual conduct with are expected to testify during the court-martial at Lackland. A seven-member jury made up of military personnel will decide the case.
At least 31 female trainees have been identified as victims in the sex scandal.
Officials at Lackland are calling Walker's court-martial the "cornerstone case" in the ongoing investigation.
"We haven't had a case of this magnitude, certainly in recent memory," said Brent Boller, a spokesman for Joint Base San Antonio, which operates Lackland.
Walker's civilian attorney, Joseph Esparza, declined to comment.
The start of the court-martial Monday is expected to mostly deal with procedural matters. Testimony in the case is not likely to begin until Tuesday.
The sexual misconduct at the base apparently began in 2009, but the first woman didn't come forward until last year. The first allegations were levied against Walker, who is accused of crimes that allegedly took place between October 2010 and January 2011.