Trial begins for third suspect accused in deadly Colorado rock-throwing case

By Jennifer McRae, Alan Gionet

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    JEFFERSON COUNTY, Colorado (KCNC) — Opening statements in the trial for the third and final suspect accused of throwing a rock into a car and killing a woman began in Jefferson County Court on Monday morning.

Joseph Koenig’s trial was initially scheduled for last summer but was rescheduled after a court-ordered evaluation when his attorneys raised concerns about an ADHD diagnosis.

Koenig is charged with first-degree murder with extreme indifference along with several counts of attempted murder and assault for throwing rocks at other vehicles.

In her opening statement, prosecutor Katharine Decker pointed out that the murder charge does not need deliberation with intent.

“The evidence doesn’t have to prove that he’s the one who threw that rock. The evidence doesn’t have to prove that he’s the one who threw anything that hit any of the other people. All the evidence has to show is that the defendant, aided, encouraged or abetted,” she said. “The issue in this case will primarily come down to whether the defendant knew he was creating a grave risk of death to others.”

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.

Defense attorney Tom Ward said the defendant didn’t intend the outcome: “Joe Koenig made reckless, impulsive and tragic choices, there’s no question about it, but he did not knowingly murder. He did not act with extreme indifference to the value of human life. In fact, he didn’t intend to hurt anyone.”

Decker said testimony will show that Koenig was driving the pickup that belonged to Nicholas Karol-Chik. She said the jury will hear testimony that the other two in the car will point at Koenig as the one who threw the rock.

“The defendant reaches across his body, grabs this landscaping rock with his left dominant hand and throws it outside the driver’s side window as she passes like a shotput,” Decker said.

But Ward raised claims that the other two in the vehicle got “sweetheart” deals for their testimony and changed their versions of events.

“Both of them have changed their stories about their involvement and about who threw that rock- the last rock of that night that killed Alexa Bartell,” Ward said.

The other two suspects in the case, Karol-Chik and Zachary Kwak, pleaded guilty after reaching plea agreements with the prosecution in Jefferson County in May 2024.

The case was broken open after investigators obtained cell phone data that they say showed the suspects’ phones in the area where, not only Bartell’s car was hit, but where other cars were hit as well.

“So what they do is they plot out those times and locations to see if there’s any suspect’s cell phone that was in those places at those times,” said Decker.

Raj Chohan, an attorney and former prosecutor who has followed the case, says the evidence against the three is strong.

“If you see that cell phone showing up with the other two cellphones and they’re all at the same place generally speaking when different incidents have happened, that becomes powerful evidence that helps to prove that those people were probably at the locations where the crimes occurred,” he told CBS News Colorado. “It’s not questionable evidence. It’s not junk science. It’s well established and used routinely in criminal courts across the country.”

The defense, Chohan expects, will do its best to go after the other two in the pickup with Koenig for their stories: “Whenever key witnesses change their story, that’s good news for the defense because it gives them something to work with. They can go after the credibility of the witnesses who change their story.”

The first testimony in the case came from Bartell’s mother, Kelly, who got a phone call from Alexa’s girlfriend Jenna Griggs the night of the incident when Alexa did not show up at Griggs’ home as she was supposed to. Kelly Bartell related a tearful story of telling Jenna Griggs to go to the area where mapping showed Alexa’s location as her mom called 911.

She was on the phone with Griggs when she found the car. Griggs also testified through tears, describing the tragic scene. She spotted the car with broken front and rear windows and blood visible, with Alexa apparently in the front seat. She had been killed instantly, officials said.

According to prosecutors, the deals with Karol-Chik and Kwak are dependent on their full cooperation, including testimony against Koenig. Investigators had previously revealed that they believed Koenig was the one who threw the fatal rock at Bartell’s car.

Sentencing for Karol-Chik and Kwak has been scheduled for after Koenig’s trial, May 1 and May 2, respectively.

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