Transcript for Air Force Academy Cadet Goes Undercover to Fight Sexual Assault
Sexual assault can often be tough to prove. With allegations at the air force academy of female cadets being victimized by players on the football team, one of the players agreed to go undercover to gather evidence. What happened to him is just part of the story. For the first time tonight, we hear from a young woman who says she was one of those victims. Here's ABC's chief investigative correspondent Brian Ross for our series, "Nightline investigates." ? In April of 2012, I was sexually assaulted. Reporter: Alexis Jones hardy was a freshman cadet at the United States air force academy. He was putting his hand down my pants and, you know, I kept saying no. I said no about 30 times. Reporter: She is speaking publicly tonight for the first time, still angry about how she was treated, not only by her alleged attacker, but by the academy, where she dropped out, her life changed forever. Honestly I gave up on life. There were times I didn't want to be alive. They don't want people to know that sexual assault is a problem at the air force academy. ? Reporter: As a school that trains the country's future military leaders, the air force academy in Colorado Springs is supposed to be a place of strict discipline. With an honor code inscribed on the walls for all to see. We will not lie, steal or cheat, nor tolerate among us anyone who does. You take an honor oath. You promise to uphold the standards of this country and to be honorable. Reporter: But her attacker, she says, was a member of the air force academy's football team. And while she reported the assault, she never named her alleged attacker, for fear he would be protected and she would be the one put on trial. I had two teammates who were assaulted. One was raped. One, it was attempted rape. And I saw what it does to them. I saw the academy as a whole judge them. Everything about their personal life was put in the forefront. Everyone they'd ever slept with. Reporter: That was a widely held view at the air force academy, according to Brandon Enos, the agent with the osi assigned to investigate sex yawl violence and members of the football team. He says the code of honor did not seem to apply to many of them. It is very difficult to get into that circle and they usually don't snitch, for lack of a better word. Reporter: But Enos found a way to break that code of silence, with an undercover cadet by the name of Eric Thomas, a soccer and football team member who agreed to become a confidential informant. I thought, absolutely. We're talking about sexual assault here. Real crimes affecting real people and having consequences that last a lifetime. Reporter: Thomas worked for almost a year as a confidential informant. They met on the vast you a cadmy campus at night, as Thomas, who wore a secret tape recorder, provided detailed reports on his fellow cadets' alleged criminal behavior. I would report a sexual assault. The information I'm providing is what every other cadet should pride. Reporter: Thomas was a gold mine of information for Enos. Leads developed by him and others resulted in what the air force called operation gridiron, whose results were not wildly publicized until the Colorado Springs gazette revealed the case late last year. Two members of the football team court martialed for sexual assault. Jamil cooks and Tony Daniels, both now appealing their convictions. A third star player, asher Clark, was disenrolled for drug use, along with 14 other cadets, many of them athletes, expelled or forced to resign. Actually the largest and most successful operation to ever be ran at the academy. Reporter: Without Eric, would you have been able to learn that, you think? No. I can confidently say there would have been no conviction at the academy probably to this day. Reporter: Without Eric. Right. Reporter: Once it became public, operation gridiron put a cloud over the good name of the air force academy. We have a microscope over us and we know that, because we are held to a higher standard. Reporter: The new suspect, Michelle Johnson, says she's the first to acknowledge there was a serious problem with sexual assault at the academy. And she says she's made it her highest priority to fix. We acknowledge it, we own it and we want to move on. Reporter: There's no denial of what happened here. No. Reporter: It was bad. Yes. Reporter: The air force academy says whatever happened in the past, sexual violence is not and will not be tolerated. It produced this video to help prove it. Featuring top cadet athletes. I pledge to end sexual violence and the culture that perpetuates it. I will not ignore the signs. I'll make every effort to fix the veerment, even if I'm not directly part of the program. Reporter: And the academy selected four to reinforce the message that everyone has to stand up to sexual I have lens. We know what we're like. We know we're not that type of person. Reporter: Do you feel if there's a problem, it gets addressed? Yes, sir, I do. I feel like now that this has been out in the media, we hold each other better accountable. Reporter: But the special investigations agent, Brandon Enos, and his undercover cadet, Eric Thomas, who helped develop the cases that held sexual predators acountable say they were both punished and then kicked out or forced out of the air force for their work. I was vacuuming floors, taking out trash. Just really degrading. Reporter: Vacuuming floors? Oh, yeah. Reporter: Thomas was told to pack his things and leave the academy grounds. Disenrolled just six weeks before graduation. We had just gotten our lieutenant bars and then I got a knock on the door. Unannounced. That I was being disenrolled. I had my rank removed in the middle of the squadron. Watched me as I rolled my chest down to the elevator. And was gone from the academy. Reporter: The air force says Thomas aqume lamented a huge number of demerits for violations including going offcampus and attending parties. Most of which he claims were part of his undercover assignment. I was punished for providing these statements. Without those statements -- I'd be a second lieutenant. Reporter: But a report by the air force inspector general found that the bulk of the demerits were not connected to Thomas' undercover work. I did not conclude that he was treated unfairly. Reporter: The final decision was made by Michael Gould. If I disenrolled him from the air force academy, he deserved it. You would not want that particular individual to be an officer in our air force today. Reporter: Do you give Eric Thomas any credit for what he did serving as an undercover informant? I don't want to talk about former cadet Thomas anymore. Reporter: The fact that he helped bring these cases, was that a good thing? I don't really buy into the fact that he helped bring these cases. Reporter: Really? Not at all? No, I'm -- I'm finished talking about his accusations. I don't buy any of us. Reporter: But even the air force inspector general found that Thomas deserves substantial credit for his role in helping to bring cases of sexual violence to light. Very positive. His work the definitely helped the osi in their investigation and later on helped obtain a couple of court martial trials. Reporter: Members of congress are looking into what happened to Thomas and up nose and two U.S. Senators are asking the Pentagon to conduct a new independent investigation. It's a case of retaliation for people whose job is to root out and prosecute sexual assault cases. Reporter: And it's not just a problem with the air force football team. In fact, one of the court martialed players, jail cooks, is now wearing number 37 for another college, Alcorn state in Mississippi. A football star there, even though he is also a registered sex offender. All to the dismay of Alexis Jones hardy, given what she says happened to her by another football player. It absolutely just disgusts men, because that proves that it's not important. Reporter: Alcorn state says it is aware that cooks is a registered sex offender, but told us they have no issues with his enrollment. As for Eric Thomas, he's now working with the victims advocates group, protect our defenders. Still hoping one day to become an air force pilot. For "Nightline," Brian Ross, ABC news, Colorado Springs.
This transcript has been automatically generated and may not be 100% accurate.