The death of a California teenager at a Utah treatment center for troubled teens last year didn’t draw much scrutiny, but the 16-year-old girl’s parents say they want to make sure that such a tragedy doesn’t happen again.

Vive Adolescent Care in St. George was ultimately fined $1,000 for not following its own and state policies after Arianna Duenez was found dead in her bed on the morning of July 2, 2023, KSTU reported. Prosecutors and police, however, found no criminal intent in what happened, so no charges were ever filed. And the death was not mentioned by media until now.

“There was no direct cause – in our investigation – between the noncompliance and the individual’s death,” Shannon Thoman-Black, the director of the state’s licensing division, said.

Investigators ruled out suicide and said there was no sign of foul play. The Utah Medical Examiner’s Office never found a cause of death, and it remains “undetermined.”

“This is a perplexing case,” said St. George Police Sgt. Adam Olmstead. “Just for the fact that any time you go out and there’s a 16-year-old who’s deceased, that’s not normal.”

Duenez’s mother, Maggie Montelongo, said her daughter had struggled for years with mental health issues and was transferred to Vive in May 2023.

“I took her there in hopes that they could help her,” Montelongo told KTSU.

Documents reviewed by the station showed Duenez had been vomiting repeatedly in the hours before she was found dead, but employees did not do 15-minutes checks as required by the facility’s protocols. Staff did “look in” on her, but did not directly assess her breathing. For 90 minutes on the morning of the girl’s death, no one looked in on her at all, although they signed off on forms saying they did. And there was no registered nurse on duty that morning.

St. George police determined Duenez had been dead for somewhere between 4 1/2 and 10 hours. She was “stiff,” “cold,” and “purple” when paramedics arrived.

Vive itself declined an interview for KTSU’s story and instead sent a statement.

“Both regulators and local law enforcement completed their investigations and neither found wrongful or criminal activity,” the statement said. “While we routinely self-reported an issue at the time, it was judged to have had no bearing on the patient’s death. We have long been cleared to accept new admissions.”

Montelongo and Duenez’s stepfather, Daniel Bisinger, are still wondering, almost a year later, if the facility had followed its own policies, would their daughter still be alive?

“Whether a defibrillator would have worked or whether it wouldn’t have, the point is Arianna never got that choice,” said Bisinger. “She never got that chance. We’ll never know. Because of their neglect.”

Montelongo said her daughter began feeling unwell after staff started her on a low dose of Suboxone, a drug used for opioid addiction but rarely given to teens. Duenez had been off drugs for seven months by that time but was still having cravings. She had a first dose on June 27, and by July 1 was still feeling nauseous.

Staff said she asked to go to bed early that night but appeared happy. At 8 a.m. the next morning, a staffer “received no response” when she went to wake the girl up and assumed she “was just refusing to get up.” A second staffer a short time later learned that wasn’t true.

An autopsy found prescribed medications in Duenez’s system but said there weren’t at toxic levels. She had a slightly enlarged heart and fluid in her lungs, but examiners could not determine a cause or manner of death and left it at “undetermined.”

Duenez’s parents are now pursuing a second autopsy.

After Duenez’s death, Vive instituted a few new policies requiring staff to see three breaths every 15 minutes and “carry flashlights for checks and night.” It also promised to have registered nurses on duty 24/7.

Despite the questions, prosecutors said they didn’t file charges ecause “there was no specific intent to do harm.” A prosecuting attorney in the office, Courtney Brinkerhoff Sinagra, told KSTU that “the appropriate avenue for those harmed in this tragic situation is to seek civil remedies through the civil lawsuit process.”

Montelongo and Bisinger have not made that decision as yet. But they are speaking out.

“The pain, the suffering is for a purpose,” Bisinger said, “and our purpose is to use that so this doesn’t happen to someone else … they don’t lose their daughter for no reason when they should still be here with us. That’s what I want people to know. That’s what has to come from this.”

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[Featured image: Vive Adolescent Care/Google Maps]