On Saturday, Sgt. Luis Walker was sentenced to 20 years in prison for counts including rape, adultery, and aggravated sexual assault in the first major case to be tried in military court from the sex abuse scandal that has rocked Lackland Air Force base in San Antonio, Texas.

The revelations at Lackland have awoken concerns about abuses in the military that haven’t made their way into the mainstream media since the 1990s. The reports of widespread abuse, coupled with the long history of crimes against women in the military, have several lawmakers pushing for a Congressional hearing about the incidents at the camp. On Tuesday, a human rights group launched a Twitter campaign that targets Buck McKeon — the chair of the House Armed Services committee — with the hashtag #AskBuck, in an attempt to persuade him to hold a hearing.

"The widespread sex abuse scandal at Lackland demands a Congressional investigation. We need to know how this behavior was permitted at Lackland for so long and by so many,” said California Congresswoman Jackie Speier in a statement Saturday.  

Twelve instructors at Lackland, including Walker, are under investigation and at least 31 women have been identified as victims of crimes that apparently began in 2009. The probe began when a woman accused Walker of sexual abuse last fall. The charges against Walker were the most severe, and reveal he had inappropriate sexual contact with 10 female recruits between October 2010 and January 2011.

For Speier, Walker’s sentence was not enough. "The military jury confirmed what we already knew, Walker is a sexual predator who used his position in the military to rape and sexually assault young recruits at Lackland. But a sentence of 20 years in confinement is inadequate for a man who abused 10 victims – 2 years jail time per victim is not justice for the women betrayed by a military leader,” Speier said in the statement.

Both a criminal investigation within the military justice system as well as a policy review by a general are underway, but Speier wants action from the Hill, and started a petition asking for a Congressional hearing. As of Tuesday, her petition had garnered 77 signatures from members of Congress, and a petition started by Protect Our Defenders, the group that created the Twitter campaign, had more than 7,000 signatures as of Tuesday.

Speier has said that since scandals like Lackland keep reoccurring every decade — Tailhook in 1991 and then Aberdeen in 1996 — the military investigations that follow are obviously not fixing the problem.

So, she wants Congress to launch its own investigation to answer the questions she thinks will otherwise not be addressed in a system that favors the perpetrator. So far, the House Armed Services committee has made no move to organize a hearing.

“Walker’s court martial conviction is still the exception and not the rule,” she said in her statement.

She posed these questions when she spoke for the third time about Lackland on the House floor on July 19, the day that Walker’s court martial began: “In the last three years since Luis Walker started working at Lackland, roughly 21,000 female Airmen have cycled through basic training. Have they been interviewed by investigators to determine if they, too, had been raped and sexually assaulted at Lackland? How widespread is this epidemic? At Lackland out of the 31 identified victims, only one has reported the crime. Why are victims scared to come forward?,” she said on the floor. “Internal investigations will not get to the bottom of this.”

Much blame has fallen on the strict power structure that military recruits are forced to adhere to, and are indoctrinated with starting on their first day of training.

Aaron Belkin, a professor of political science at San Francisco State University and director of the Palm Center, which studies gender and military issues, at the UCLA law school, told the San Francisco Chronicle that the unlimited authority instructors have over recruits becomes similar to a “master-slave dynamic,” and that often results in rape.

It’s this corrupt system that allows these sweeping crimes to go unreported that Speier wants to take the hearing out of; in her statement, she cited that last year, out of 19,000 military rapes and sexual assaults, only 3,200 victims reported the attacks and only 191 cases resulted in court martial conviction.

The women who spoke against Walker in court all testified to the same thing; they were afraid to come out and say what had happened — afraid they’d be punished, forced to redo their training, or kicked out of the military. They were recruits and Walker was an instructor. And for many, he was the instructor they reported to directly.

The New York Times reported that a witness said Walker called her into his office and forced her to show him her breasts. She told other recruits about the incident, and Walker found out and called her back into his office.

“If you had a problem with it, then you should have come to me, instead of running your mouth,” Walker told the witness, according to her court testimony. “Remember, I’m staff sergeant, you’re a trainee.”

It’s exactly that power dynamic that makes Speier want to reform the military’s crime reporting system with the STOP Act, H.R. 3435, a piece of legislation she introduced last fall that would create an independent entity outside of the Department of Defense chain of command that would review cases of sexual assault and rape.

Lackland Air Force base is where all American airmen go to get basic training, and where they get their first taste of that chain of command. The base sees 35,000 recruits a year, who undergo eight weeks of basic training. While one in five of recruits are female, only one in 10 of the 475 instructors are.

The women who testified Saturday against Walker said what he did to them made it difficult for them to trust authority, and has haunted them since, according to the Los Angeles Times.

"It’s made it extremely hard to interact with authority figures," a witness said. "During my tour in Afghanistan, I was a little bit more scared of everything. I can’t work with certain individuals just since they remind me of Staff Sgt. Walker."

Walker could have faced life in prison, and the defense asked for a lenient sentence so that he could have a life with his wife and two young sons, who were all at the trial. On the stand, his wife pleaded, "Spare at least some of his time in the sentence. I don’t want my boys to grow up without a father."

But the jury, composed of two officers and five enlisted airmen, also heard women who claim they were abused by Walker and say they can’t sleep at night, and have advised their female relatives not to join.

"I don’t enjoy the military anymore," an alleged victim said. "I don’t want to be in it. I’m scared to open my door to anyone."