Washington (CNN) "I am sorry. I have been sorry. I will always be sorry for raping you."

In a 20-minute long phone call in 2013, Air Force Lt. Col. Michael Briggs confessed to raping SSgt. "DK" in 2005. After receiving a call from the victim, Briggs detailed how he went to her room after a long night of drinking, pushed himself on her and continued to have sex with her despite pleas for him to stop.

A recording of that call would be played in a military court in 2014. Briggs would be tried by a judge, found guilty and sentenced to five months in prison. He would be dismissed from the Air Force and registered as a sex offender.

It was understood, based on military law and reinforced through legal precedent, that there was no statute of limitations for rape in the military. Though the assault occurred in 2005, and Briggs was not accused for eight years, defense counsel did not even raise the issue of statute of limitations at trial.

But last year, the top military appeals court came to a different understanding. When presented with a separate rape charge brought years after an alleged incident, it found that a five-year statute of limitations existed before 2006. The decision eventually led to Briggs' rape conviction -- and the convictions of at least three other service members - being vacated.

This one decision has reverberated through the entire military court system. It has not only vacated convictions. It has prevented at least 10 new cases from being heard, the Justice Department says. This comes as #MeToo trickles through the armed forces

The military is plagued by a 38% increase in sexual assault, reported by the Pentagon this spring, and grapples openly with how to prevent it. "It is a cancer within an organization, and we got to crush it," now-Chairman of the Joint Chiefs of Staff Mark Milley said recently.

The Justice Department has asked the Supreme Court to review and reverse what it describes firmly as a "misunderstanding of the law." Allowing it to stand would "subvert the military's concerted effort to eradicate sexual assault, erode confidence in the military-justice system, and fuel the impression that 'nothing will happen to the perpetrator.'"

It's using the taped confession to get there.

The rape

In her first ever media interview, DK shared her account of the rape. CNN has agreed to not share DK's name in order to protect her privacy.

She remembers the night in flashes.

She remembers going out to drink with a girlfriend. Drinking too much. She remembers a knock at her door after returning to Mountain Home Air Force Base in Idaho. Telling him no, pleading with him to stop. She remembers rolling her body away from him and struggling to get away. Michael Briggs pulling her back. She remembers the pain ... the moment she gave up and passed out beneath the weight of him.

She also remembers the blood.

The following is from a transcript of their call

"I bled for days afterwards," she said. "I couldn't sit down. I was so bruised and swollen. What—"

"Oh, my God," he says.

"What did you do to me?"

Briggs shared that he met up with DK and her friend that evening. After a night of drinking together, he went back to his room and waited.

DK had been helped to her room, by the friend, when he knocked on her door.

"I was pretty drunk," Briggs tells DK, though he acknowledges several times that he was in better shape than she.

Then, he raped her.

"I'm so sorry for pushing myself on you," he says on the call. "For not respecting you as a person and listening to you and stopping."

Maybe he raped her because of "you, know, off-duty stress in my life or whatever," he suggests. Not that that's an excuse, he adds.

Maybe it was his age and maturity at the time. "I was young and immature and, um, younger— um, younger and immature and, um, had a— didn't have an appreciation for, uh, everyone as human beings..."

Maybe he did it because he liked her. "You're like a little sister," he tells her. "I was really fond of you; really into you. I think that was obvious."

Maybe he raped her because of their prior interactions. "Uh maybe I used your—you know, your—how you reacted to me when we were, you know, sober when we were at work, when we were not drunk, um, as like what you really, really wanted instead of listening to you when I needed to," he says.

"I told you it hurt," DK says. "I tried to get away from you. I told you to stop. Why didn't you listen to me?"

"Um-"

DK presses him.

"You raped me. You destroyed me. For eight years, I have had to live with this by myself. I can't talk about it; I can't tell anybody. You took everything from me. Why?" she asks.

"I didn't know the repercussions and even if I did I wasn't — I was selfish. I was —"

"I need to hear you say you are sorry for raping me," she tells him.

"I am sorry. I have been sorry. I will always be sorry for raping you," Briggs says.

The conversation was approximately 20 minutes long.

"All those years of repressing, it really was as bad as I thought it was," DK told CNN.

Unbeknownst to Briggs at the time, DK was sitting in a government vehicle on an Air Force installation with two agents from the Air Force Office of Special Investigations (AFOSI) and a special victims counselor holding a phone that AFOSI had rigged with a recording device.

"I was sitting in the driver's seat just staring out the window," she said. "As soon as he hung up, I started telling them he'd apologized ... I'm telling them he confessed."

As they listened to the recording, DK says her whole body shook. Her account had been validated.

"It was that moment of I didn't lie, I told the complete truth," she told CNN. "He's even backing it all up."

After the call ended, Briggs searched the statute of limitations for rape, a Justice Department filing says. Documents from Briggs' appeals show the evidence was obtained from his government issued computer.

Briggs pleaded not guilty and was tried by military judge on Spangdahlem Air Base in Germany, where he was stationed at the time.

On August 7, 2014, Briggs was found guilty and sentenced to five months confinement. He was dismissed from the Air Force and issued a letter of reprimand.

The rape conviction provided DK with some sense of closure. The five-month sentence, less so. The prosecution had asked for eight years.

"Hearing the verdict be read, I cried a little bit on my husband's shoulder. It was like finally everybody knows the truth. He did this; he can't run from this anymore," she said. "He took so much of who I was that night and now finally everyone will know why."

For once, it seemed, the system had worked.

"I do have to say this on the record -- the Air Force took amazing care of me," DK told CNN. "There was never a point in any of it that I felt anything but cared for by the military, by the Air Force. The entire process. Everyone I talked to was on my side and honest and upfront and it was- it was- I did not have the experience that a lot of victims have."

DK says she was medically discharged from the Air Force in 2015 following the trial.

The appeal

This March, years after the five-month sentence had been served, DK says she received a call at work.

Briggs had won an appeal . The rape conviction would be set aside, his record would be wiped clean and he could be eligible to receive back pay and benefits from the Air Force.

"I was so inconsolable. Pacing and crying and sobbing and shaking," she told CNN.

Before Briggs' appeal , the Court of Appeals for the Armed Forces had heard another rape case that highlighted a conflict between military law and a 1977 ruling by the US Supreme Court.

There is a distinction between military and civilian law. Enacted by Congress, the Uniform Code of Military Justice (UCMJ) is enforced by the military with its own trials, judges and appeals courts. There are crimes and punishments unique to the military. For instance, it is illegal for an officer to say bad things about the President. In civilian law, this would violate free speech.

Historically, under military law, crimes must be charged within five years.

However, in 1986, Congress exempted any crime that was punishable by the death sentence from the five-year statute of limitations. Rape was among those offenses.

In 2006, Congress revised the UCMJ again, making clear that rape could be prosecuted "at any time without limitation."

The top military appeals court revisited the issue last year, when presented with US v Mangahas. Lt. Col. Edzel Mangahas had been accused of rape 18 years after an alleged 1997 assault at the US Coast Guard Academy.

The appeals court referred to a 1977 Supreme Court decision in a non-military case. In Coker v Georgia , the Supreme Court ruled that imposing the death sentence for rape was "cruel and unusual" punishment in violation of the Eighth Amendment. In US v Mangahas , the appeals court determined that because death would never actually be imposed for the crime, rape did not qualify for the 1986 exemption and should fall under the five-year statute of limitations.

The charge and specification of rape against Mangahas were dismissed.

A gray area emerged for prosecuting rapes that occurred in the military between 1986 and 2006.

Over the last 18 months, Briggs and at least three other service members have had their rape convictions set aside citing Mangahas.

The Justice Department filing shows at least 10 more cases have been dismissed.

"Lt. Col. Briggs has consistently maintained his innocence in this case," said his appeals lawyer Steve Vladeck. "But the question the government is asking the Supreme Court to decide is not what actually happened between him and DK, but the more technical legal question whether the military has the power to court-martial servicemembers for offenses that allegedly took place well over a decade ago, and in which, according to the highest court in the military, the statute of limitations had already expired."

(Vladeck, a professor at the University of Texas School of Law, is a CNN contributor.)

Retired Col. Don Christensen was the chief prosecutor for the Air Force between 2010 and 2014. He also served as trial counsel, defense counsel or military judge for 23 years. He is now the president of Protect our Defenders, an organization devoted to ending rape and sexual assault in the military.

"Prior to [the Mangahas] decision coming out, everybody knew that there was not a statute of limitations for rape in the military. Everyone. It was accepted," Christensen said. "Look at what the intent of Congress was. And it's clear that Congress in '86 changed the statute of limitations, in 2006 changed the statute of limitations. They did not want a statute of limitations. Period."

Rep. Brian Mast, a combat veteran, is leading a bipartisan effort in Congress to condemn the appeals court's ruling.

"This wasn't intended by the military. This wasn't intended by the Congress or anybody else. Those that have committed these crimes are not going to be set free on the technicality of a falsely created statute of limitations by a court that was not meant to create law," the Florida Republican said in a recent interview.

"Misunderstanding of the law"

Late last month, the US Justice Department petitioned the Supreme Court to review and reverse the appeals court's decision.

"Recognizing that sexual assault within the military is devastating to the morale, discipline, and effectiveness of our Armed Forces, but also difficult to uncover, Congress long made rape a capital offense and has enabled rape to be prosecuted whenever it is discovered," wrote US Solicitor General Noel Francisco.

The government's weapon is Briggs and his taped confession.

In addition to excerpts from the recording, Francisco points to the vacated rape convictions and 10 known cases that have been dismissed outright without being heard. These are cases, he wrote, that the military would have pursued had it not been for this "misunderstanding."

Sexual assault, the military agrees, is a problem.

The Pentagon released a report in May that said sexual assaults across the US military increased by a rate of nearly 38% from 2016 to 2018.

Last year, then-Defense Secretary Jim Mattis repeatedly called sexual assault a "cancer" in the ranks.

In July, Gen. Mark Milley also used the word "cancer."

Milley is now chairman of the Joint Chiefs of Staff, the highest military position in the land.

President Donald Trump's pick to serve as the number two military officer under Milley was accused of sexual assault by an army colonel. The Air Force Office of Special Investigations cleared him and Gen. John Hyten himself strongly denied the accusations during his confirmation hearing last month.

If the Supreme Court chooses to take on US v Briggs, it would be a first. The justices have yet to weigh in on a related #MeToo issue and on the simmering controversy over how the military addresses sexual misconduct in its ranks.

It would also mark the first high-profile sexual misconduct case since Justice Brett Kavanaugh was confirmed last fall. During his confirmation hearings, Kavanaugh was accused of sexual assault while a teenager. Both he and his accuser Christine Blasey Ford testified before the Senate Judiciary Committee. He vehemently denies the claims.

The Supreme Court will likely not consider the request to hear the case until it returns for its new term in October. Briggs has until mid-August to reply to the Justice Department's filing.

DK says she's ready for the high court to hear the appeal.

"I was silent for eight years," she told CNN. "I'm not going to sit by this time."