"Have you ever been so mad at anyone that you want to kill them?"
Steven Schweigert told DuPage County jurors Thursday that Jeffrey Keller asked him that question in Schweigert's Texas apartment on Jan. 9, 2015, before Keller admitted to killing Nate Fox.
"'Well, I did. I was so mad at someone that I killed him,'" Schwiegert testified Keller told him.
Keller is charged with five counts of first-degree murder in the slaying of Fox, a 37-year-old car salesman and former International Basketball League player, at Fox's Bloomingdale townhouse on Dec. 22, 2014.
First Assistant State's Attorney Joe Ruggiero, in his opening arguments Wednesday, said Keller stalked Fox before gunning him down as he left his vehicle in his driveway on the 200 block of Tamarack Drive.
Prosecutors say Keller held a delusional belief that Fox was having a romantic relationship with a woman Keller was having an "emotional affair" with.
Prosecutors allege Keller became angry and accused the woman of having a relationship with Fox, with whom she previously worked at an insurance agency. Despite her denials, prosecutors said, Keller was obsessed with the thought of her being with another man.
"Jeff told me Nate was messing with someone or something he shouldn't have been messing with," Schweigert said. "He wanted to get rid of the 'problem.'"
Schweigert said Keller told him how he hid and waited for Fox to arrive before ambushing him as he exited his car. Schweigert said Keller told him he shot Fox three times in the chest and regretted not going back to Fox's body and delivering a "kill shot" to ensure Fox was dead before he fled the scene.
"He said he chickened out," Schweigert said.
Ruggiero previously said Fox actually was shot twice, once in the hand and once in the shoulder.
Schweigert said he drove Keller to the airport the morning after the confession and wished him luck before calling Bloomingdale police that afternoon.
Two days later, Schweigert flew to Chicago and provided videotaped statements to police before also agreeing to participate in audio-recorded telephone conversations with Keller.
In the conversation, played in court Thursday, Keller apologized to Schweigert for "burdening him" with the information and said his emotions after the shooting have been the "strangest thing I've ever felt in my life." He also said Fox was "in a place he didn't belong, doing something he shouldn't have been doing."
When Schweigert told Keller he was having a hard time processing the information, Keller told him to "wash that stuff out of (your) mind." Keller said when they were both 60 he was going to take Schweigert to an exotic island where they could kick back and talk about all the crazy things they had done in their lives.
"This would be the craziest," Schweigert said.
Keller has been held without bail since his Jan. 15, 2015, arrest.