Left: Alexa Bartell (Jefferson County Sheriff’s Department). Right: Joseph Koenig (Jefferson County Sheriff’s Department).
The scene inside a Colorado courtroom looked a grim picture of human action on Friday as a young and condemned man testified to his onetime best friend’s alleged glee in violence.
Joseph Edwin Koenig, 20, was a high school senior, but 18 years old, when he and two friends were charged with “extreme indifference” murder over the April 19, 2023, death of Alexa Bartell, 20.
On the day in question, the windshield of the victim’s Chevy Spark was struck and smashed by what authorities termed a “large landscaping rock.” The impact sent the young woman’s car careening “off the roadway” on a remote stretch of road in Jefferson County.
Bartell died a horrible death in the ensuing crash; prosecutors previously testified the victim’s brain was found in her backseat.
“There was biological matter on the roadway,” a deputy sheriff who led the murder probe testified during a hearing in October 2023.
In May 2024, two codefendants in the case, Nicholas “Mitch” James Karol-Chik, and Zachary Kwak, pleaded guilty to lesser crimes, and substantially lesser crimes, respectively. They both agreed to testify against Koenig during his jury trial in Jefferson County District Court.
Each of the codefendants, to varying degrees, played instrumental parts in the rock-throwing that night. But Karol-Chik was admittedly more culpable than Kwak, having also taken part in additional such attacks in February 2023 and even days before in early April 2023.
On Friday, Karol-Chik told jurors Koenig let out an excited whoop as he saw Bartell’s compact car drive off Indiana Street and through a fence in a field near the Rocky Flats National Wildlife Refuge, according to a courtroom report by the Denver Post.
“He was excited,” the witness told the jury, referring to the defendant. “He would just look at us with this big smile on his face.”
On that fateful night, several landscaping rocks were thrown at other cars, both in motion and parked. But some claimed details are mixed.
Kwak maintains he did not throw any of the rocks at all that night, according to the Post. Instead, Kwak earlier testified he only collected the rocks from multiple parking lots and then handed them over to the two front-seat passengers, who threw them.
The speedometer in the teenagers’ vehicle was 103 mph just before the 9.3-pound rock was thrown that took Bartell’s life, Kwak also previously testified. Karol-Chik, however, said the car was doing 80 mph. Both men said Koenig sped up before the final, fatal attack.
Karol-Chik went on to say the celebratory whooping and smiles were in line with how the trio had generally acted over the thrown rocks that night; when a rock struck a car, they would express delight; when a rock missed a car, they would express disappointment.
“We only thought of them as cars,” the witness continued. “But we never thought of who may be driving them.”
Each of the defendants was initially charged with first-degree murder, attempted murder, assault in the second degree, and attempted second-degree assault. Kwak took a plea deal on three assault charges: one count of first-degree assault on Bartell and two counts of second-degree assault for attacks on three other victims. Karol-Chik pleaded guilty to one count of second-degree murder.
Even with plea deals, Karol-Chik and Kwak face decades behind bars; they are slated to be sentenced on May 1 and May 2, respectively.
Koenig, for his part, has conceded some responsibility. His lawyers insist he should only be convicted of manslaughter because none of the rock-throwers had the intent to kill, or even harm, anyone else.
The defense is also hinging some hopes on long-inconsistent statements from Karol-Chik, who for several months told prosecutors that Kwak was the one who threw the rock that killed Bartell.
Only during a fourth and final proffer interview — an interview in service of a plea deal — did Karol-Chik finally tell investigators Koenig was the person responsible for the woman’s death.
At the time, he and Koenig were best friends and “almost close enough to be brothers,” Karol-Chik reportedly told the jury. The lies came during three out of four proffer interviews, because Koenig and Karol-Chik agreed to pin the crime on Kwak, who they barely knew, during a discussion after seeing emergency vehicles later that night.
“We went over everything that happened and it was at that time that Joe said to me that we wouldn’t have to worry about it, we’ll just say that Zach did it,” Karol-Chik testified on Friday.
On cross-examination, however, Karol-Chik also said he long believed Kwak had actually thrown the rock, according to the Post.
The witness testified he remembered remarking on the sheer size of the rock, recalling he told Kwak it was too big to throw and being rebuffed. Karol-Chik went on to say he remembered Kwak saying he would throw the rock if Karol-Chik would not.
Then, the state worked to clean things up a bit.
“Was the truth that Joseph Koenig threw the rock that killed Alexa Bartell?” a prosecutor asked on redirect.
Karol-Chik replied in the affirmative.
This coming week, jurors will decide who and what to believe. Closing arguments are scheduled to end by April 21.
Love true crime? Sign up for our newsletter, The Law&Crime Docket, to get the latest real-life crime stories delivered right to your inbox.
Matt Naham contributed to this report.
