Joseph Koenig’s attorneys wrapped up their case Wednesday — but testimony in his murder trial didn’t end until after a return to court of one of his co-defendants.

Nicholas “Mitch” Karol-Chik — who faces between 35 and 72 years in prison after pleading guilty to a series of rock attacks that ended with the death of Alexa Bartell — returned to the witness stand at the behest of prosecutors who wanted to rebut earlier testimony suggesting that teenagers are susceptible to impulsive behavior and don’t always perceive the risks of their actions.

Karol-Chik had previously admitted that he and Koenig were involved in multiple episodes of throwing rocks and other objects — including concrete and a fiberglass garden statue — at oncoming cars.

After testifying for nearly four hours last week, Karol-Chik returned to court Wednesday wearing pale green jail scrubs with his wrists shackled to a belt wrapping his waist. He took the seat in the witness stand less than 10 feet from where Koenig sat at the defense table.

His appearance was brief.

“How many nights of similar rock-throwing incidents were there involving you and Mr. Koenig in total?” prosecutor Katharine Decker asked.

“I would say between February and April of 2023, uh, there were at least 10 separate nights that we went out,” Karol-Chik said.

“And on those at least 10 separate nights that you and he went out, were there multiple rocks you threw?” Decker asked.

“Yes,” Karol-Chik said.

“No further questions,” Decker said.

Defense attorney Martin Stuart asked just a few questions himself – eliciting Karol-Chik’s agreement that seven of the incidents involved throwing rocks at parked cars.

Closing arguments are scheduled for Thursday morning and the jury should get the case later in the day.

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