The indictment of former megachurch pastor Robert Morris on child sex abuse charges this week was made possible by an accuser who refused to quit, a novel legal theory and an archaic section of state criminal code that dates to Oklahoma’s origins on the wild frontier.

Morris, a leading national figure in the American evangelical movement and the founder of Gateway Church in Southlake, Texas, was charged Wednesday with five counts of lewd or indecent acts with a child. The indictment by a multicounty Oklahoma grand jury came nine months after Cindy Clemishire publicly accused Morris of repeatedly molesting her over a four-year span when she was a child in the 1980s.

Clemishire was 12 and dressed in flowery pink pajamas the first time she says Morris touched her. It was Christmas night in her childhood bedroom in Oklahoma. It would be their secret, she recalled him saying afterward.

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After Clemishire went public with her account in June, Morris released a statement confessing to what he described as “inappropriate sexual behavior with a young lady.” Days later, he resigned as senior pastor at Gateway. Following news of his indictment this week, a Gateway spokesperson said church leaders were “grateful for the work of the justice system in holding abusers accountable for their actions.”

Morris didn’t respond to messages requesting comment.

When she spoke out last year, Clemishire had little hope that Morris would face legal consequences. The statute of limitations for bringing a civil lawsuit or criminal charges had long since expired. 

Or so she believed.

Enter Oklahoma Attorney General Gentner Drummond. Twenty years ago, when the Republican lawyer was still in private practice, he represented Clemishire — an old family friend — as she attempted to negotiate a settlement with Morris over her allegations, which she first brought to church leaders in the 1980s. The 2005 deal fell apart when Clemishire refused Morris’ demand that she sign a nondisclosure agreement, Drummond said. That was the end of his involvement in the matter, he said, but the case stuck with him.

After Clemishire’s accusations made national headlines last year — helping spark a reckoning over the handing of sex abuse allegations at Gateway and several other North Texas churches — Drummond said his prosecutors asked for permission to pursue a criminal investigation, and he gave it.

“I frankly have walled myself from that investigation and prosecution and was pleased that the grand jury believed that there was enough evidence to indict Mr. Morris,” Drummond told NBC News in an interview Thursday.

Drummond’s office expects Morris to turn himself in to authorities next week.

The prosecution turns on what Drummond called an “extraordinarily unusual” application of “a very old statute” that is most often used when prosecuting cold cases. More than a century ago, when outlaw cowboys roved the Old West committing crimes as they moved between states, Drummond said Oklahoma and other frontier states implemented a provision that essentially pauses — or tolls — the statute of limitations when someone commits a crime and then flees the state.

Morris was a traveling evangelist who preached to crowds at churches and revivals across the Southwest when he entered Clemishire’s life in the early 1980s. Like the out-of-state marauders who terrorized Oklahoma towns in the early 1900s, Morris did not reside in Oklahoma, so Drummond said his office determined that the statute of limitations did not apply.

“Certainly that will be challenged in a court of law, and we are prepared to meet that challenge,” Drummond said. “I anticipate that there will be, ultimately, case law made on this case.”

Tracy Pearl, a professor at the University of Oklahoma College of Law, said the attorney general’s interpretation appears to be supported by case law.

“And from a policy perspective, I think these sorts of provisions that toll the statute of limitations when somebody is located out of state makes sense,” Pearl said. “We don’t want to disadvantage the state or prosecutors in cases in which they may have a really limited ability to find the defendant and then extradite them back to the state.”

In an interview Thursday with NBC News, Clemishire called the announcement of criminal charges surreal. She said she and her family felt validated after years of struggling with the trauma she says Morris inflicted on her as a child.

“We’re deeply grateful to the authorities that have worked tirelessly to make this day possible, and we remain hopeful that justice will ultimately prevail,” she said.

After Morris resigned from Gateway, the church hired an outside law firm to investigate its handling of the allegations. In November, the church announced it had dismissed elders and church employees who knew about Clemishire’s allegations or should have done more to investigate them.

In a statement following Morris’ indictment, a Gateway spokesperson said church leaders “continue to pray for Cindy Clemishire and her family, for the members and staff of Gateway Church, and for all of those impacted by this terrible situation.”

In response to Clemishire’s story, Texas state Rep. Jeff Leach, a Republican, has introduced legislation to give more rights to victims of childhood sexual abuse, including extending the time period that victims have to file lawsuits against their attackers or those who enabled them. Clemishire testified in support of changes during a Texas House committee hearing in October.

In Oklahoma, Drummond told NBC News that he supports eliminating the criminal statute of limitations in cases of rape. In the meantime, he said he hoped Morris’ indictment inspires more survivors to come forward.

“If you are a victim of child abuse, one, my heart goes out to you,” he said. “Two, if it occurred in the state of Oklahoma, contact me. Let’s not assume that we cannot bring your offender to justice.”

If you are a child being abused, or know a child who may be facing abuse, call the Childhelp National Child Abuse Hotline at (800) 422-4453, or go to www.childhelphotline.org. States often have child abuse hotlines, but if you suspect a child’s life is in imminent danger, call 911.