MADISON, Wis. -- Former University of Wisconsin-Madison student Adam Peterson has been bound over for trial in connection with the January stabbing death of Joel Marino.

VIDEO: Watch The Report | VIDEO: Peterson Tapes

Twenty-year-old Peterson faces one count of first-degree intentional homicide in the death of Marino.

Peterson is accused of attacking Marino at the victim's south side home on Jan. 28.

Assistant district attorney Corey Stephan on Friday played tapes of calls Peterson made from jail to his parents in which he confesses to killing Marino in a robbery.

Peterson's father, Melvin Peterson, can be heard telling his son he was not in his right mind.

Defense attorney Dennis E. Burke didn't challenge the content of the calls and entered a not guilty plea on Peterson's behalf.

According to the criminal complaint, police tied Peterson to the crime through DNA evidence from a knife found near the crime scene, WISC-TV reported.

The conversation between Peterson as his dad goes as follows, according to court documents:

"Do you want to tell me anything more about it, was this a stranger?" said Peterson's dad.

Said Adam, "Yeah."

"I just ... I felt so numb and I wanted money," said Adam. His dad responded, "You wanted money?"

"Yeah," said Adam.

"Oh, so it was an attempted robbery?" said Peterson's dad.

Adam responded it was and his dad asked, "Were you on drugs at the time?"

"No," said Adam.

Said Adam's dad, "You weren't ... you weren't either drunk or on drugs?"

Adam told his dad no and his father then said, "OK, so you attempted robbery and you brought a knife with you?"

"Yeah," said Adam.

Said his father, "You did? Wow ... wow."

Said Adam's father, "Did you know when you left the scene that he was likely dead?"

"No. I stabbed him, he was like, 'What the hell?' But I thought that would be it," said Adam.

"Was it another co-ed or another student?" said his dad.

Said Peterson, "No, he was just a working man."

"You asked for money (inaudible) ... did he give you it? Did he resist, is that why you stabbed him?" said his father.

Adam responded, "No, I just like walked. I just stabbed him out of nowhere."

During the phone conversation, Peterson's father also addressed his son's mental state at the time of the stabbing, according to the complaint.

Said his father, "You would not do something like that if you were in your right frame of mind."

"No," said Peterson.

"That's all that there's to it, OK?" said his father.

Peterson, who is a former UW student, was arrested at his mother's home in Grant, Minn., near Stillwater and charged last month. He was extradited to the Dane County Jail in Madison.

He told his mother detectives didn't trick him into confessing, according to the complaint.

"They (police) didn't talk you into this?" said Peterson's mother.

Adam responded, "No."

Said his mother, "You actually did this?"

"I actually did this," said Adam.

Adam sat in the courtroom emotionless as prosecutors played the recordings. In another taped conversation, Peterson's mother asked why he hurt Marino. Peterson responded, "That was part of the plan," WISC-TV reported.

It was emotional evidence that brought tears to many in the courtroom -- including Marino's father, Lou Marino, WISC-TV reported.

"There's not much I can say at this point other than it's incredibly hard to be in the room with someone who (allegedly) murdered your son, that's for sure," Lou Marino said after the hearing.

The judge made the ruling that there is enough evidence to move the case forward.

Peterson's father and twin brother were both at the hearing -- both declined to comment.

Peterson pleaded not guilty and there is not yet a date set for when the trial will be, WISC-TV reported.

According to Chris Van Wagner, one of Madison's longtime criminal defense attorneys, the taped conversations between Peterson and his parents now present a new set of questions, he told WISC-TV by phone.

Van Wagner said the trial will now examine what Peterson's "plan" actually was. He said the defense may try to argue Peterson's intentions did not include killing Joel Marino, WISC-TV reported.

Peterson is currently being held on $1 million cash bail.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.