Sherri Papini's theatrics are what got her caught, detectives say

The detectives who worked on the case of Sherri Papini, the woman who pleaded guilty Monday to faking her own kidnapping and lying to the FBI about it, said it was her over-the-top theatrics that tipped them off to her lies.

Papini, a mother of two from Redding, California, was arrested last month, nearly six years after she was reported missing. On Nov. 24, 2016, three weeks after she vanished, she was found 146 miles south, on Interstate 5, with a chain around her waist.

She had injuries that authorities now believe were self-inflicted and a brand on her shoulder that she blamed on her abductors, federal authorities said last month. She was also emaciated.

Watch the full interview Friday on “Dateline” at 9 p.m. ET/8 p.m. CT

Shasta County Sheriff Sergeant Kyle Wallace and Captain Brian Jackson, who have worked the case since Papini was reported missing, told "Dateline" in an interview that something wasn't right from the start.

A tuft of Papini's hair was found with her phone near the spot where she said she had been abducted. She told detectives she purposefully pulled it out when her captors took her at gunpoint so her husband would be able to know where she was taken from.

"Yet when you look at just the hair alone, hindsight, it was theatrical and not really what fit what she said in her story," Wallace said. "I think, ultimately, being able to look at each piece of evidence now with the clarity of what was going on, not just in the moments, but the drama or the theatrics that Sherri brought with every step of this investigation was really part of the undoing."

Papini also refused to fully cooperate with investigators upon her return, Wallace and Jackson said. Her husband was eager to find her kidnappers, but Papini made up a story about her abduction’s being connected with law enforcement. She would often withhold from investigators or refuse to provide certain details.

Papini had told police that two Hispanic women took her. But investigators found male DNA on Papini's clothing — DNA that led them to her ex-boyfriend, whom she had been staying with the entire time she pretended to be missing.

The former boyfriend told investigators what he knew. He told them Papini asked him to hit her — he would not, but he agreed to hold a hockey stick for her to run into and to pelt her with hockey pucks. He also branded her when she asked him to.

"I have never heard of anything like this. Not even kind of," Wallace said. "She was dedicated" to her story.

To make matters more difficult for the investigators, most of Papini's lies had truths behind them — she was able to describe what it felt like to be branded, because she really had been.

"A lot of the lies that she told us had a lot of truth to it. So it’s really hard to decipher," Wallace said.

Papini told the ex-boyfriend, whom she hadn't dated in 15 years, that she needed refuge from her abusive husband. He drove hundreds of miles to pick her up and rearranged a room to her liking when she arrived.

"He truly is a nice person," Wallace said.

The ex-boyfriend has not been charged with a crime.

"I think the easiest way to describe it is he was doing what a friend asked," Wallace said. "Because she asked to be hit, she asked to be burned, and he just went along with what she said, it’s two consenting adults.

"And as far as him not coming forward, you know, after he realized, you know, what was going on, there’s, there’s no law that, you know, makes somebody have an obligation to report what they know," Jackson said.

Papini, meanwhile, was charged with mail fraud and lying to a law enforcement officer — the charges stem not from her faked abduction but from the deception, she continued after she returned.

The detectives said that had she told the truth when she returned, she would have been criminally clean. But she had already spent too much time crafting the lie.

"Because, again, we didn’t know if it was an abduction or if she just left. So, going and talking to her, we laid out that," Jackson said. "'Did you just want to leave?'

"Then, once you saw the bruising and all that, again, like I said, the theatrics of it — she obviously couldn’t come off that — the abduction story after she mutilated herself," he said.

Papini is scheduled to be sentenced July 11. She was ordered to pay more than $300,000 in restitution to federal, state and local agencies.