One of five teenagers who prosecutors say were part of a Washington County drug-dealing chain pleaded guilty to third-degree murder Friday in the overdose death of a Woodbury girl.

Cole A. Matenaer, 19, of Woodbury, pleaded guilty to providing a designer psychedelic drug similar to LSD that killed 17-year-old Tara Fitzgerald on Jan. 11, just hours after she took it.

Fitzgerald, a Woodbury High School junior who had been in good spirits after posting a strong score on a college-readiness exam, died from an overdose of the substance known as 25i-NBOMe, sometimes called "N-Bomb" or "Smiles," according to the state Bureau of Criminal Apprehension.

The unusual case reflects the growing alarm among law officers that the dealing of dangerous drugs, especially to youths, has reached crisis proportions in Washington County, across the metro area and elsewhere in Minnesota.

Washington County prosecutors have taken a hard line in their approach to prosecuting crimes involving drug overdoses and synthetic drugs, including targeting the supply chain of those drugs. Three of those charged in Fitzgerald's case were 17 at the time charges were filed and were certified as adults for prosecution.

"When an illegal drug enters our community, all of those involved — those who create it, sell it or give it away — are responsible for what happens with that drug," Washington County Attorney Pete Orput said in May.

Fitzgerald and a girlfriend who was staying overnight each placed a dose on their tongues for 20 minutes and then swallowed it. Police later found that the girls' cellphones contained videos of them under the influence of the drug, according to a criminal complaint filed in May.

The girlfriend called her mother the next morning when she heard Fitzgerald moaning. The mother called 911 and then Fitzgerald's parents — Tom Fitzgerald and Mai Hoang Fitzgerald — at work. They hurried home, but it was too late.

Fitzgerald's parents said later that they were stunned that their daughter, described by those who knew her as an "exceptional" student with a bright future, was involved with illegal drugs.

"She was such a joyful, super talented, spunky kid," her father said in an interview after charges were filed.

Matenaer's plea Friday was "a straight plea" involving "no plea agreement," according to Fred Fink, head of the criminal division in the Washington County attorney's office.

Matenaer is scheduled to be sentenced on Oct. 10 by Washington County District Judge Richard Ilkka. Fink said Friday that a prison sentence of 74 to 103 months is likely, though the judge has discretion.

Others charged with third-degree murder in Fitzgerald's death were Sydney C. Johnson, now 18, of Woodbury; Alistair C. Berg and Brian P. Norlander, both 17 and of Woodbury; and Alexander L. Claussen, 19, of St. Cloud. The murder charges relate to the sale and distribution of controlled substances.

Johnson, Berg and Norlander also face a second felony charge — sale of dangerous drugs to someone under 18.

According to the criminal complaint in the case:

The Woodbury defendants were buying and selling the LSD, which was supplied by Claussen, who dealt the drug from a place he called "the castle." Norlander gave the drug to Fitzgerald after a series of sales that involved the other defendants.

Emergency responders were dispatched to Fitzgerald's home Jan. 11 because she "was not breathing and was unresponsive after reportedly experimenting with a substance similar to LSD." She was pronounced dead after her arrival at Regions Hospital in St. Paul.

The complaint also said the drug was packaged in a tinfoil wrapper that contained two small square pieces of paper, or "tabs," that were light pink in color.

By all accounts, Fitzgerald was a happy and active teenager. An honor student, she read several books at a time and enjoyed softball, skateboarding, the Beatles and Coldplay. She also was proud of her Vietnamese and Irish Catholic backgrounds.

The day before she died, Fitzgerald learned that she scored well on her ACT, the college-readiness exam. To celebrate, she had a friend stay over that night. Her parents, sleeping upstairs, said they heard the girls laughing and talking until midnight. Sometime after that, police say, the girls took the drug.

Matenaer was arrested several days later. Police found 34 doses of the substance that had been used by Fitzgerald in his car. Investigators had already tracked the web of drug sales through Woodbury High School, but it was Matenaer's cellphone records that led them to Claussen, who was at the top of the local supply chain.

Investigators set up a drug buy at Claussen's St. Cloud home in April, using a confidential informant. After the informant bought five doses of what turned out to be 25i-NBOMe, a search warrant was obtained. The search turned up 305 doses.

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Jim Anderson • 651-925-5039