Teen pleads guilty after throwing landscaping rocks through windshield and killing 20-year-old driver

Alexa Bartell, 20, was killed after three teens threw rocks at cars in April 2023

Zachary Kwak pictured in court in May 2023 (Copyright - 2023 The Denver Post, MediaNews Group.)

One of three Colorado teens charged in the killing of a driver who had a rock smash through her windshield, has pleaded guilty after reaching a deal with the prosecution.

Zachary Kwak, 19, appeared in court on Friday a year after he, Joseph Koenig and Nicholas “Mitch” Karol-Chik, threw landscaping rocks at passing cars on 19 April 2023, injuring multiple drivers and killing 20-year-old Alexa Bartell.

Kwak pleaded guilty to one count of first-degree assault, one count of second-degree assault and an added count of criminal attempt to commit assault, according to Fox31.

He was previously charged with murder but pleaded guilty as part of a plea deal which requires him to cooperate. The two other teens are still being prosecuted on first-degree murder charges. Karol-Chik and Koenig have both pleaded not guilty.

Zachary Kwak (far left), pleaded guilty in the deadly Colorado rock throwing, while Joseph Koenig and Nicholas Karol-Chik have both pleaded not guilty (Jefferson County Sheriff’s Office)

Prosecutors allege that the three teens, who were all 18 at the time, drove around in Karol-Chik’s pickup truck, loading it up with landscaping rocks they took from a Walmart.

Bartell’s friend told police she was on the phone with her while she was driving when the young woman “abruptly stopped talking,” according to the Jefferson County Sheriff’s Office (JCSO).

After the call went silent, the friend tracked Bartell’s location with a phone app and found the suburban Denver woman dead in her car, which had crashed into a field.

Alexa Bartell, 20, was killed after she was hit in the head with a rock that was thrown through the windshield of the car she was driving (JCSO)

After noticing they had struck the victim’s windshield with a rock, the three suspects turned around and drove by her crashed vehicle while  Kwak allegedly took a picture of her car as a “memento”, prosecutors said.

The teens were arrested several days later.

In exchange for Kwak’s guilty pleas, prosecutors dropped other more serious charges against him, including first-degree murder.

Kwak faces between 20 and 32 years in prison and will be sentenced after 3 September, when Karol-Chik and Koenig are scheduled to be tried separately.