When Nicholas “Mitch” Karol-Chik told interrogators that the night of April 19, 2023 wasn’t the first time he’d thrown objects at moving cars, the admission was a bombshell.

This week, First Judicial District Judge Christopher Zenisek ruled that information from Karol-Chik’s video-taped interview about the “prior acts” of rock-throwing can be admitted at Joseph Koenig’s upcoming murder trial scheduled to begin in April, but only during the prosecution’s rebuttal of a psychiatric defense witness.

Alexa Bartell, 20, was killed when a rock was thrown through her windshield as she drove near the Rocky Flats National Wildlife Refuge.

One pivotal question as the trial in the rock-throwing murder of the Arvada woman gets closer is: Exactly how many times previously did these bizarre incidents happen?

At issue is whether defendant Koenig’s actions were those of an impulsive teenager whose brain was not mature enough to know right from wrong. On the other hand, prosecutors said he had plenty of practice.

Karol-Chik told investigators that he and Koenig hurled objects at oncoming vehicles on at least 10 separate nights but in a motion obtained by The Denver Gazette, defense attorneys counter that Karol-Chik’s statement was vague and “lacked detail.” Defense attorneys also maintained in the document that only “one or more” incidents occurred, not 10.

If there were as many as 10 object-throwing incidents with weeks in between them, then Koenig must have had time to think about his behavior, prosecutors have contended in court.

However, if this was a random night of teenaged mischief fueled by peer pressure, then maybe he couldn’t help himself, court documents indicate. 

Dr. Lawrence Steinberg, an expert in adolescent brain development, is expected to testify Koenig only threw the large rock because he was experiencing a feeling of “hot cognition,” a state of mind when emotions control the thought process, resulting in risky behavior.

The prosecution introduced its counter in the mental health expert battle when it advised the court that forensic psychiatrist Alexandra Lynch would be testifying for its side. 

Though three people were in the truck that night, Koenig alone was charged with Bartell’s murder plus multiple counts of attempted murder, assault, and attempted assault for incidents he’s alleged to have committed from February through April 2023. 

The other two defendants, Karol-Chik and Zachary Kwak, took plea deals and are expected to testify against Koenig for his role in a bizarre night of mischief which turned deadly. 

What happened

At 10:45 p.m. April 19, 2023, Bartell was driving home and talking to a friend on the phone when the line went silent.

Investigators believe that at that moment she was hit by a landscaping rock which was hurled at her car by a group of teenagers in an oncoming truck.

The rock came at her vehicle so hard and fast that it crashed through the windshield, hit her in the head instantly killing her, and exited the back window before it came to rest on the side of the highway. 

The incident happened near the 10600 block of Indiana Street near Rocky Flats Wildlife Refuge.

Koenig, Karol-Chik and Kwak, all age 18 at the time, had already hit six other cars in a span of less than 45 minutes between 10 p.m. and 11 p.m., damaging those vehicles but not hurting anyone, according to court documents. 

Arrest records show that Joseph Koenig was driving the truck, Karol-Chik was in the passenger seat and Kwak was sitting in the back, mostly handing the rocks up front to be launched. The vehicle belonged to Karol-Chik, documents said.

Not much is known about exactly who threw what rock at which vehicle, but Kwak told investigators that Koenig was the one who threw the large landscaping rock that killed Bartell. 

However, Karol-Chik told Jefferson County Sheriff’s investigators that it was Kwak and that the night of rock-throwing was Kwak’s idea. 

The fact that Kwak told investigators it was the first time he had ever gone on a rock-throwing spre, appeared to challenge that statement.

Prosecutors have said in court and in motions that rocks were not the only items that Koenig and Karol-Chik threw at moving vehicles. They are also alleged to have thrown a concrete statue head and a vehicle fender, according to court records.

As the months rolled on leading up to the trial and the evidence shook out, Zenisek decided in December 2023 that the three teens should have separate trials. 

Eventually, the case became two-against-one. 

Each of the three suspects was initially charged with first-degree murder but Karol-Chik and Kwak pleaded guilty to less severe charges and are expected to testify against Koenig during his murder trial, which starts April 11 in Jefferson County.

Kwak told investigators he had only recently met Karol-Chik and Koenig, but the story he told Jefferson County Sheriff’s deputies revealed he was plenty involved with the killing. Kwak said to them that, after they hit Bartell’s car, the three made a U-turn and drove by to see the damage that they had done. 

Kwak and Karol-Chik will not be sentenced until after Koenig’s trial is over. 

The trial promises to be well-attended as the parents of all three defendants have been present in the courtroom as have scores of Alexa Bartel’s family and friends. 

Her parents have not missed a court date and have opted not to speak to the press. 

Defense attorney Martin Stuart declined to comment on the case.

Koenig’s next court date is a pre-trial conference set for April 4.