Transcript for Minnesota Student's Alleged Mass-Shooting Plans Revealed
captured on tape, the chilling words of a teenager accused of plotting to bomb his school and kill his parents. He's heard calmly telling the police in detail about his plot. Mara schiavocampo has that this morning. Reporter: John Ladue was arrested after a neighbor saw him heading to his weapons storeroom. And now, we're learning about his alleged plot. And we're learning it from him. This morning, a never-before-heard interrogation tape shared Tuesday, John Ladue, shares details about his alleged murder plot. My plan was to steal a recycling bin from the school. And take one of the pressure cookers I made and put it in the hallway and blow it up. Reporter: The tapes document his alleged plan to commit the assault. On the tape, Ladue tells investigators he wanted to first kill his parents and sister. Why would you dispose of your family. What have they done? They did nothing wrong. I just wanted as many victims as possible. Reporter: Before moving on to the school, where he says he wanted to plant bombs and attack survivors as they fled. I would detonate while people were fleeing, just like the Boston bombings and blow them up, too. And my plans were to enter and throw molotov cocktails and pipe bombs. Reporter: Police say Ladue's plan was a year in the making. And testing homemade bombs, seen in this youtube video. Even hiding an explosive in an Elmo doll. I am the one who is responsible for the CO2 bombs at Hartley elementary school. Reporter: He never wanted to hurt children. And criticized sandy hook shooter, Adam Lanza. But what he didn't tell investigators, a motivation. Simply saying, he has psychological issues. I think I'm just really mentally ill. And no one's noticed. And I've been trying to hide it. Reporter: Hiding his violent fantasi fantasies, from everyone, including his father. He thinks I'm a good kid because I can lie pretty well and persuade him I'm just ordinary. Reporter: A seemingly ordinary teen, accused of an extraordinary plot. Ladue has pleaded not guilty to the charges, which includes attempted murder. His next hearing will determine if he will be tried as an adult. Dan Abrams is here. Before I get to that question. Let me ask you about the tapes that we just heard. How will they play? They will be very important pieces of evidence, in connection with this case. The charge here, the most serious charge is attempted murder. It's starting to sound like his family is suggesting he never would have actually done it. These were just fantasies. Things he had thought about. But was never going to actually act on. And that's why the tapes are going to become really important because if it ultimately gets to a jury, it may not. But if it did, they would have to evaluate how realistic was this? Was this the rantings of a mentally ill person who never intended to go through with this? Or was it the actual intent of someone who was going to go forward and try to kill these people? He went into great detail. And the fact that his voice is so calm. It sounds so certain and so smart, I think all of that will be a big problem for him. We heard what Mara was saying about juvenile court. In Minnesota, if you're accused of this kind of crime, there's a presumption it goes to the adult court. The child has the burden to prove why it shouldn't go. There's a presumption it moves to adult court. And he's 17. We're going to turn to another case. This is an exclusive interview with peter roger, the father of Elliot roger, the young man who
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