3 Teens Killed Woman by Hurling Large Rock at Car, Then Snapped 'Memento' Photo. Now They're All Convicted

A Colorado man was convicted of first-degree murder-extreme indifference in the death of 20-year-old Alexa Bartell, who died after a rock crashed through her car window while she was driving.

A jury on Friday, April 25, also found Joseph Koenig, 20, guilty of multiple counts including criminal attempt to commit first-degree murder, assault in the second-degree and criminal attempt to commit murder in the first-degree for other rock throwing attacks.

“Despite a conviction of murder in the first degree — extreme indifference — none of this ever had to happen,” Jefferson County District Attorney Alexis King said after the verdict, the Denver Gazette reported.  

“It’s hard to be happy or feel satisfied that justice was served today,” Alexa’s mother, Kelly Bartell, said, per the Gazette. “It doesn’t fill what amazing life was lost. And three others were also lost and impacted.”

Koenig’s friends Zachary Kwak and Nicholas “Mitch” Karol-Chik pleaded guilty last year for their part in the attack, per CBS News.

The three friends were hurling rocks at passing cars at approximately 10:45 p.m. on April 19, 2023, when one of the rocks – a large nine-pound landscaping rock – smashed through Bartell’s driver’s side window. At the time, Bartell was on the phone with a friend and driving northbound in the 10600 block of Indiana Street in Denver.

When police and emergency medical workers arrived at the scene, they found Bartell with a large head wound and no pulse.

The rock was found nearby with traces of blood on it, per CBS News.

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Her car was “the last of a series of vehicles struck by large landscaping rocks in a spree that began shortly after 10:00 p.m. that night at 100th and Simms in Westminster,” according to a Jefferson County Sheriff’s Office press release.

“[Koenig] was excited,” Karol-Chik, who pleaded guilty to second-degree murder and attempted first-degree murder, testified about Koenig’s reaction after he hit Bartell’s car, per the Gazette. “He kept turning from his seat to look at me and to look at Zach in the back seat. He would just look at us with his big smile on his face.”

After the attack, Koenig, Kwak and Karol-Chick, who were 18 at the time, allegedly returned to take photos of the crime scene “as a memento,” according to court documents obtained by NBC News.

The following day, they met up to coordinate their stories and become “blood brothers,” vowing not to speak of the attack to anyone, per NBC News.

During the trial, Koenig alleged that it was Kwak who tossed the fatal rock.

Koening’s sentencing is scheduled for June 3, per 9News. He’s facing life in prison for the first-degree murder charge, and could get sentenced for the other charges to serve at the same time, Denver Gazette reports. Kwak could get 20 to 32 years and Karol-Chik 35 to 72 years.