The third and final defendant was sentenced to life in prison without the possibility of parole in a Jefferson County, Colorado courtroom on Tuesday for his role in a deadly rock-throwing case. A jury found Joseph Koenig guilty of first-degree murder in April after he threw a rock through the windshield of Alexa Bartell's moving vehicle, killing her.

In court on Tuesday, the judge sentenced Koenig to life in prison without the possibility of parole, which is a mandatory sentence required by law, plus 60 years for the other counts to be served consecutively. Koenig received 769 days of presentence confinement credit.

Koenig was also found guilty on 18 other counts for his role in throwing rocks at other vehicles in a series of incidents in Jefferson County that caused damage to vehicles and injuries to drivers.

During the sentencing hearing, Bartell's mother gave an emotional statement. 

These moments, these milestones, were stolen from her and from me and from all of our family by these three individuals who made a conscious decision to hurl a rock through her windshield. They watched her car run off the road into the field, turned back and watched them, then got rid of the evidence, drove back to get a better look twice, took photos, whooped, and drove away. They never called for help. They made no effort to save her. Instead, they formed a pack to be blood brothers, as if taking my daughter's life was something to be proud of," said Kelly Bartell. "Alexa was my only child, my daughter, my best friend and the greatest joy of my life."

Koenig spoke before the judge handed down his sentence, "Nothing I say can give you one more minute with her, and I know that it is my fault that she is gone every day since she died. It is the first thing I think of when I wake up, and the last thing that I think of when I go to sleep. I never knew Alexa, and I didn't get the chance to even meet her, but from what I've learned about her, she must have been a very special person, and I know that the world is a worse place without her in it.

"I have no excuse, and I have no explanation for what Mitch, Zach, and I did that night. But I hope you believe me when I tell you that we didn't intend to hurt Alexa or hurt anybody else that night. I mean, looking back on it now, it seems obvious that someone was going to get hurt or killed," said Koenig. 

Two co-defendants, Nicholas "Mitch" Karol-Chik and Zachary Kwak, pleaded guilty last year for their roles in the 2023 attack. Both men testified against Koenig as part of their plea agreements. Both claimed that it was Koenig who threw the rock that killed Bartell.  

Last month, Kwak was sentenced to 27 years in the Colorado Department of Corrections for the first-degree assault charge relating to Bartell's death, five years in the DOC to be served consecutively for a second-degree assault charge in the series of rock-throwing attacks and another sentence of eight years in the DOC to be served concurrently for another count of second-degree assault for a total of 32 years in prison with 738 days credit for time served.   

The day before Kwak's sentencing, Nicholas "Mitch" James Karol-Chik was sentenced to 45 years in the Colorado Department of Corrections after reaching a plea agreement with prosecutors. Last May, he pleaded guilty to his role in a series of rock-throwing attacks between Feb. 25, 2023, and April 19, 2023.

Twenty-year-old Bartell was struck and killed late at night on April 19, 2023, when she was struck by a rock that was thrown into her windshield. Several others were injured in similar incidents with what authorities described as "large landscaping rocks," concrete, and in one case, a statue.     

Her mom said losing her daughter has impacted every facet of her life, "It didn't just change my life. It changed who I am. Losing my daughter didn't just break my heart. It broke me. It shattered my soul. Everything I see and live is different now, my desires, my dreams, my relationships, all are touched by this grief. There isn't any part of my life that has not been touched by grief. My family will never be the same."

At a news conference following the sentencing, Kelly Bartell said that she and her family are preparing for the possibility of an appeal by Koenig.