After learning that his 19-year-old daughter probably died of hypothermia after ingesting large amounts of methamphetamine and psychoactive drugs, Kevin Byrne is imploring young people to use a buddy system when they're out with their friends and urging parents to communicate with their children.

"It's about so much more than just staying together and talking to your kids," Byrne said emphatically. "For young people, a buddy system increases your chances of staying alive ?— always. For parents, having truly honest conversations with your kids, even the uncomfortable ones about drugs, is what we need to be doing to protect them."

Byrne's statements followed a newly released autopsy report on his daughter, Alyssa Byrne, whose body was discovered in a snowbank three days after she wandered off from the SnowGlobe Music Festival in South Lake Tahoe on New Years Eve. According to the El Dorado County Sheriff's Department, Byrne most likely froze to death. But Lt. Pete Van Arnum said that while the cause of death was most likely hypothermia, drugs found in the teen's system could have played a part in her death.

"While she most likely died of hypothermia due to prolonged exposure, the methamphetamine levels in her system were toxic and she had taken multiple psychoactive drugs," said Van Arnum.

After hearing the news, Kevin Byrne said he and his family were stunned. "I know for a fact that she had never used meth before," said Byrne, who acknowledged that his daughter had experimented with drugs in the past. After Alyssa admitted to her parents that she had been using prescription amphetamines, the teenager agreed to submit to a drug test in November. Byrne said the comprehensive screening revealed Alyssa had taken the attention deficit disorder medication Adderall — an amphetamine and dextroamphetamine drug popular with teens because of its easy access and euphoric highs. He said that Alyssa Byrne did not have ADD or ADHD and added that no other drugs were found in his daughter's system at the time.

"We talked to Alyssa about drugs because we knew that, these days, drugs would be a part of her life," said Byrne. "One of the drugs we talked about was meth, because it is the up-and-coming drug, readily available and cheap. She had always said she had never tried it and had no desire to try it. She was honest about her drug use in the past, so I have no reason to doubt her now."

Byrne said the only explanation he can think of for methamphetamine being in her system is that his daughter did not know what she was taking. He said several friends who were at the concert with Alyssa told him that they were taking drugs at the music festival. But, they told him, they believed they were taking something other than methamphetamine. Byrne declined to say what they thought they were taking.

Oftentimes, big concerts such as the three-day SnowGlobe Music Festival feature a rave-like atmosphere where the use of MDMA, or "ecstasy" is widespread. Drugs like ecstasy not only offer a euphoric high, but also provide increased energy. In general, ecstasy and drugs like it are cut with other, cheaper drugs to improve profits. Methamphetamine is a popular choice to cut MDMA with, due to its low pricetag and similar euphoric effects. According to the National Institute on Drug Abuse, in some cases ecstasy pills do not even contain MDMA.

Lt. Van Arnum said the investigation into Alyssa Byrne's death is ongoing and added that authorities are trying to track down where the teenager purchased the drugs.

But regardless of the exact circumstances, Byrne said the autopsy results are all the more reason for young people to have a buddy system when they go places together.

"I still believe having someone with her would have helped her," said Byrne. "I don't blame any of her friends, but we've got to get this message out there. If they had witnessed anything, if they had been with her, if all the kids had taken responsibility for one another, maybe she would have found her way back."

This belief has led the Byrne family to promote a program called Petaluma "Always Buddy." It targets middle- and high-schoolers, encouraging them to pledge to seek safety in numbers and to call a trusted adult at the first sign of trouble — advice that Byrne admitted is tough to get young people to follow. Friends of Alyssa's first told authorities that Alyssa had been drinking the night she disappeared, when the autopsy showed Alyssa had no alcohol in her system. Byrne said it has taken time to get the young people with her to admit what drugs they were taking at the festival.

"But I would ask anyone who is afraid of getting their friends into trouble: Would you rather be uncomfortable, or would you rather lose someone?" said Byrne.

Byrne added that many parents have asked him what else they can do for their children. He says that continuing to openly communicate with children and their friends is all a parent can do.

"Young people are adults too and they are responsible for themselves," said Byrne. "But I would urge parents to ask more questions, find out who their young adults are with, talk to their friends and their friends' parents."

Byrne, who debated whether to try to dissuade his daughter from attending the concert, said that being honest with children about not wanting them to go places — even if they still go, is a step in the right direction. "What's the worst conversation you can have with your kids, if they still come home at the end of the day?" he asked.

(Contact Janelle Wetzstein at janelle.wetzstein@arguscourier.com)