How Did One Woman Help Take Down Powerful Polygamist Leader Warren Jeffs?

Rebecca Musser wore red when she walked into a Texas courtroom to testify against the man who had once threatened to “break” her.

Warren Jeffs — the leader of the Fundamentalist Church of Jesus Christ of Latter-Day Saints — was on trial for child sexual assault after prosecutors alleged that he married teenagers and children as part of the polygamist religion he led.

Musser, a former member herself, helped put Jeffs away for life with her testimony while wearing a color that had been forbidden in their strict, religious community, according to "Dateline: Secrets Uncovered," airing Wednesdays at 8/7c on Oxygen.

It was the final showdown between the adversaries, who had clashed for years ever since Musser began to question some of the reclusive community’s ways.

Musser, one of 25 siblings, was once a devout member of the FLDS, where she was known as “Sister Becky.” The women in the sect wore prairie dresses and kept their long hair swept up in braids as they were taught to “keep sweet,” a phrase used to convey the idea that women should be obedient and do whatever is asked of them.

Rebecca Musser on Dateline Photo: NBC

Musser’s father enrolled her and her siblings in the FLDS school known as Alta Academy, where they learned the tenets of the FLDS faith.

It was there that Musser first crossed paths with Warren Jeffs, who served as the school’s goofy, yet unyieldingly strict, principal.

“There was always a calculated part of him, about what his next best move was, whether it was for power or position, but I never felt completely relaxed around him,” Musser said.

Jeffs was the son of FLDS prophet Rulon Jeffs, who was believed among his followers to speak directly to God.

“Warren was an authority in the school. He was close to the prophet and Warren would talk to him every single day and kind of be his father’s messenger,” Musser recalled.

Musser tried to practice the required obedience, but often found herself in conflicts with the principal.

“I was always in trouble for being stubborn and so, and I would ask the question, ‘Why? That doesn’t make sense to me.’ If God’s a God of reason, how come this doesn’t make sense?” she said of her early run-ins with Warren Jeffs.

 When she was 19 years old, she was assigned to marry the 85-year-old prophet Rulon, becoming his 19^th wife in September 1995.

“I just resigned myself to the fact that that was my fate and just surrender myself to it,” she said of the marriage. “I just remember walking in and feeling like, just stand up and do your duty.”

Musser found herself at odds with her now-stepson Warren Jeffs once again after refusing to visit Rulon when he had summoned her for sexual relations. Musser was once again called to Warren's office.

“He used scripture to tell me it is your duty to be a comfort to your husband, especially my husband, because he was the prophet,” Musser said. “And he said, ‘Don’t you ever, ever, ever, ever tell your husband no again. If you do, you will be destroyed in the flesh.”

Just three years into their marriage, Rulon suffered a stroke which left him debilitated, but Warren ordered the women to keep his father’s condition a secret and continued to marry his father off to more and more young women, eventually totaling 65 wives.

Warren slowly gained control of the group and began to arrange marriages for girls who were younger and younger.

Musser’s sister Elissa Wall was just 14 years old when she was pressured to marry her first-cousin Allen Steed. Musser tried to intervene to stop the marriage, but Warren insisted the wedding would be carried out and he presided over the nuptials himself.

“There was no choice for her except to do what she was told,” Musser said.

According to Wall, Steed was “incredibly sexually abusive” to her and raped her during the marriage. She tried to seek help from Warren, who she said told her to go home and give herself “mind, body, and soul” to her husband.

When Rulon Jeffs eventually died at the age of 92 in 2002, Warren officially assumed the role as the new prophet and leader of the group.

As a new widow, fear gripped Musser when she noticed that Warren had quietly begun to marry some of his father’s wives. She worried that she could be next.

“I knew that even the little freedoms that I had would be taken,” she said.

Her fears nearly came to fruition after she was caught kissing another man and Warren called her into his office, threatened her, and ordered her to be married in a week’s time.

“I begged him, I said, ‘Please, don’t do this to me,’ and he said, ‘You know that’s what God wants,’ and I said, ‘No, I don’t,’ and he pointed his finger at me and he said, ‘I will break you,’” Musser recalled.

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Before the deadline ever came, Musser fled the community in the middle of the night, leaving behind the only life she had ever known.

She went to Oregon to live with her brother, who had also left the FLDS, got a job working as a waitress, and began to find her new normal — but her encounters with Jeffs were far from over.

Wall eventually left her husband and the FLDS community, too, and headed to Oregon to join her sister. While Wall was now safe, Musser knew that she had other siblings and female cousins who were still in danger of being forced to marry as underage teens and decided to encourage Wall to file criminal charges against Warren Jeffs and Steed.

“I thought I can’t sit by and let this happen,” Musser recalled. “If there was a way that I could have stopped it and I didn’t, I don’t know if I could have lived with myself, knowing that.”

In 2006, Warren Jeffs was charged with two counts of rape as an accomplice — but he had already gone on the run two years earlier, even earning a spot on the FBI’s Most Wanted fugitive list.

He was finally apprehended in August 2006 outside of Las Vegas as he was traveling with his “favorite” wife Naomie Jeffs.

The next year, Musser and Wall would both serve as key witnesses against the man they once believed was their prophet in a sensational trial that captivated the nation.

“I looked him square in the eyes and we both nodded slightly as if to say, we meet again,” Musser recalled of taking the stand.

Warren Jeffs was found guilty in September 2007 and sentenced to 10 years in prison, but it wouldn’t be the last time he’d square off with Musser in the courtroom.

She also played a critical role in the April 2008 raid of the FLDS Yearning for Zion ranch in April 2008.

The community had been built in western Texas to house the FLDS’ most dedicated and pure members as they waited for God’s second coming.

Their seclusion would be interrupted, however, after a woman claiming her name was Sarah Barlow called into a Texas family crisis center to report that she was the teenage bride of a man named Dale Barlow and was being held at the ranch against her will, according to Peacock’s “Preaching Evil: A Wife on The Run with Warren Jeffs.”

Fearing for the teen’s safety, law enforcement descended on the property and spent days searching for the elusive Barlow, seizing evidence of other potential crimes during their search.

Investigators never did find Dale Barlow — who, it turned out, was a fictional person made up by a woman in Colorado with a history of mental health problems — but they did find more than 700 pieces of evidence inside a sacred temple on the property leading to other criminal charges against Warren Jeffs.

The evidence included a white bed used as part of the group’s religious ceremonies, priesthood records of Warren's activities, and a chilling tape seemingly depicting Warren Jeffs having sex with his 12-year-old bride as his other wives looked on.

“Not only had Warren been the perpetrator and the predator on these young girls but he had in a very twisted sense taken the thought, the idea, and called it holy,” Musser said.

Musser had been on hand at the time to help investigators decipher the evidence they discovered.

“She was very important for authenticating the documents for us,” Wes Hensley, an investigator in the Texas Attorney General’s office, told “Dateline: Secrets Uncovered.”

So, in 2010, Musser once again set out to testify against Jeffs — whose conviction in Utah was overturned that same year after the Utah Supreme Court ruled the trial judge had given the jury improper instructions.

With none of Jeffs’ underage wives being willing to turn against him, it was up to Musser once again reveal the dark secrets within the strict community during his sexual assault trial.

This time, Warren Jeffs’ conviction would lead to a life sentence.

“I bless the state of Texas that somebody finally stood up to this man and he’s sitting in prison now for the rest of his life,” Musser said, later adding, “The power of words means breaking your silence.”