So Hirte, Weyauwega-Fremont High School's salutatorian and star athlete, showed his friend a memento of the killing – the victim's car keys.
Eric Wenzelow, 19, who has known Hirte since the fourth grade, still didn't believe him, Wenzelow testified Monday on the opening day of Hirte's trial.
So Hirte showed him an 8-inch-long hunting knife he said he plunged twice into 37-year-old Glenn Kopitske's back after first shooting him in the back of the head and then turning the man over and stabbing him so deep in the chest he had difficulty pulling out the knife. Still, his friend didn't believe.
"I just didn't think he did it," Wenzelow testified. "I couldn't imagine he did it."
Whether Hirte, 19, killed Kopitske in the man's rural Winnebago County home in July 2003 is not contested by the defense. In October, Hirte admitted he killed Kopitske, but pleaded not guilty by reason of insanity.
Blames homosexual encounter
During opening statements Monday in a Winnebago County courtroom packed with Hirte's former classmates, family and friends as well as Kopitske's family, Hirte's defense attorney said two psychiatrists will testify that he was insane.
Gerald Boyle blamed the killing on an alleged homosexual encounter between Hirte and Kopitske, an incident Hirte didn't mention to doctors until he recounted the details of the night of Kopitske's death a second time. Boyle said despite Hirte's image as a successful student leader who excelled at sports and academics, he was lonely and unhappy.
"One of the torments he had, he didn't understand his own sexuality," Boyle told the jury.
Boyle said Hirte and Kopitske had a sexual encounter at the home where Kopitske lived alone, and Hirte, ashamed and angry, later returned with a shotgun and hunting knife to kill the man.
However, District Attorney William Lennon called Hirte's assertion a "preposterous story." Lennon said Hirte didn't feel any rage or shame "because the whole homosexual episode didn't take place."
Lennon plans to call as witnesses psychiatrists who examined Hirte and determined he was not mentally ill.
For someone whom Wenzelow called "the smartest guy in school," Hirte couldn't keep his mouth shut. Days after Kopitske's mother found her son's nude body, Hirte confessed to Wenzelow, his girlfriend and other classmates at Weyauwega-Fremont High School. He provided details of the killing, comparing the sound of blood coming from Kopitske's head to water pouring from a cup, and brandished the victim's car keys like a trophy.
Girlfriend recounts boasts
It wasn't until his girlfriend contacted authorities in January 2004 that detectives finally got a break in the case.
At the urging of investigators, Olivia Thoma, who is expected to testify today and has since broken up with Hirte, called him and listened as Hirte described killing Kopitske while detectives taped their conversation.
Clad in jeans and a wrinkled, untucked white shirt, Hirte doodled on a yellow legal pad Monday and rarely looked up during opening statements and testimony.
During the months before Kopitske's death, Lennon said, Hirte had become obsessed with the idea of killing a human being.
"Gary Hirte was a young man who presumably had everything," said Lennon. "Gary Hirte was the All-American boy who even had time to work at the Dairy Queen."
But the prosecutor said Hirte had an "evil side" and thought about killing someone. "If he could do it, he wondered how he would feel. Gary Hirte wondered if he'd be able to get away with it."
Lennon noted that after Hirte killed Kopitske, he remembered to collect shotgun shell casings and the gloves he wore during the homicide.
Wenzelow said he and Hirte used to drive around at night, and one night happened to drive down a Town of Wolf River road past the home of Kopitske, a man described as eccentric and schizophrenic .
On that night - about a week before the slaying - Hirte told Wenzelow that would be a good place to rob and kill someone, Lennon said in his opening statement.
The trial is expected to last several days.
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