Inside the Case of a Teen 'Thrill' Killer Whose Diary Revealed Disturbing Confession: 'It's Pretty Enjoyable'

The brutal 2009 murder of Elizabeth Olten has continued to haunt a Missouri community, partly for the crime itself but also for the motive.

The reason Elizabeth's teenage killer committed the crime, she said, was that she wanted to know what it felt like to kill.

The shocking case was in the news again earlier this summer when the killer, Alyssa Bustamante, who was 15 at the time of the slaying, was denied a chance at parole. 

The murder, and Bustamante’s attempt at getting released, ultimately compelled lawmakers to change Missouri’s state laws regarding underage criminals convicted of murder when Gov. Mike Parson signed legislation for which Elizabeth's family had advocated.

Here’s what happened:

Elizabeth's Murder

Patty Preiss called police on Oct. 21, 2009 after her 9-year-old daughter never returned to the family's St. Martin's, Mo., home from visiting a friend’s house that evening. Police eventually found the young girl buried in a shallow grave with her throat cut. She had been stabbed and strangled, according to local Fox 2.

The Disturbing Motive

Police were led to Bustamante after finding “written evidence” at the crime scene that implicated the teenager — who was a neighbor of Elizabeth's — in the murder, according to ABC News' reporting at the time. After an investigation, authorities also uncovered Bustamante’s social media pages, which included references to wanting to know what it was like to kill someone, as well as a diary in which she confessed to the crime.

“I just f------ killed someone,” the teenager wrote in her diary, according to ABC. “I strangled them and slit their throat and stabbed them now they’re dead. I don’t know how to feel atm [at the moment].”

She added: “It was ahmazing. As soon as you get over the ‘ohmygawd I can’t do this’ feeling, it’s pretty enjoyable. I’m kinda nervous and shaky though right now. Kay, I gotta go to church now…lol.”

Investigators interrogated Bustamante for more than two hours while she confessed to the crime. The teenager’s grandmother was in the interrogation room the moment her granddaughter admitted to the murder. The grandmother burst into tears and ran out of the room in shock. 

Bustamante was sentenced to life in prison in 2012 after pleading guilty to second-degree murder, according to local KOMU.

“The world lost an innocent little girl who hoped to be a teacher and a veterinarian,” her family said in a statement, according to the outlet, adding that Bustamante’s sentencing was “extremely difficult” for them to sit through.

How the Case Changed Missouri Law

New legislation signed in the summer of 2024 would appear to cement Bustamante's life sentence for good.

Because Bustamante was a juvenile at the time of the killing, she was eligible for parole due to a 2014 U.S. Supreme Court ruling. According to CNN, the court ruled 5-4 that no juvenile could be sentenced to life in prison without the chance at parole – even for murder. However, state lawmakers in Missouri passed a bill in 2021 that said that ruling does not apply to juveniles who committed first-degree murder. 

In 2024. Pason signed legislation expanding on that law to include juveniles convicted of second-degree murderers, according to local ABC 13. Elizabeth's family had advocated for that legislation.