Transcript for A college party, a confrontation outside, a student charged with murder
Reporter: Steven Jones was either a scared college freshman in fear for his life -- Why would they even try to chase me? Why would they do this to me? I don't know them. He was surrounded, bullied, threatened, and attacked. Reporter: Or a murderer who retaliated by gunning down four fraternity brothers at northern Arizona university, killing one of them? There was no threat to his safety. In fact, with that gun in his hand he was the most deadly person in sight. Reporter: It was during an off-campus party on October 9th, 2015 at this apartment complex known as the courtyard that tragedy struck. Partygoers hear what sounds like an argument. It wasn't a memorable night until everything went south. Reporter: Zack volpo is a delta ki brother who was there that night. There's a verbal confrontation going on in the street. All of a sudden I see the group move into the parking lot. That's when I saw the flashlight flick on. Reporter: Zack runs across the street into the N.A.U. Parking lot, and he's horrified. His fraternity brothers Colin bruin and Nick peering are down. Both had been shot twice. I was in so much shock I had no idea. I saw a puddle of blood next to me. Reporter: So you are second floor up, second window in, right there. Yes. Reporter: Mikey Scollard a sophomore at N.A.U. Jumps from her bed and runs down to the parking lot. You begin to see people on the ground. Yes. And the first person I see is Nick. Reporter: What Mikey doesn't realize is at this moment the shooter is still on the scene, right behind her. Before you know it there's more gunshots. You're literally administering first aid to somebody who'd been shot and you hear gunshots behind you. I hear gunshots and they say he's still shooting don't move, don't scream. Reporter: That's when the two fraternity brothers Nick Prado and Kyle zintek were hit pl Nau police begin arriving with body cameras rolling. I've got one here with a gunshot wound to the chests. Reporter: This video shows the chaos still unfolding. The young boys bleeding, lying shot on the ground. Mikey Scollard applying pressure to Nick peering's wounds. And on the other side right there a quick glimpse of a frantic 18-year-old on the ground. But this one is being handcuffed. Turn around. On the ground! Please go help them. I'm so sorry, please. Please go help them. I'm so scared. I have one detained. He identified himself as the shooter. Reporter: The hysterical shooter on that body cam is Nau freshman Steven Jones. Please. I'm so scared. I want my mom. Stand up. Is your name Steven? Yes, sir. You identified yourself to me as the shooter. Nobody else. None of my friends -- There's nobody else involved? No. Nobody but me. I take all the responsibility. Okay. Reporter: 20-year-old Colin brew lay dead on the ground while his three fraternity brothers are raced to the hospital with multiple gunshot wounds. But in the back of that squad car the suspect, Steven Jones, isn't acting like a deranged rampage shooter. More like a distraught kid. Oh, my god. Officer. How bad are they hurt? I don't know yet. Reporter: Repeatedly begging for his mom. I'm so scared. Can I call my mom? Just have a seat over there in that chair. Reporter: The teenager is led ton a tiny interrogation room, still handcuffed. Are you going to leave me in here alone? Reporter: And when he's finally able to see the blood on his hands -- That's fine. Reporter: Horror at what they have allegedly done. That's fine, Steven. Reporter: At first reluctant, Steven begins to describe a tame night at a different party. Until he says his group somehow loses track of one of the friends. Looking for him, Steven says one of them knocked on the door of the party at the courtyard. Ten or twelve dudes came out and they started like like talking . Get the Off our porch. And wen we were -- we just decided to turn around and walk away. What were they saying? I'm going to kill you, you . I bet you couldn't go back to the freshman dorms. They were obviously very drunk. Toxicology reports would later prove that Colin brew was in fact very drunk. More than three times the legal limit. And he also tested positive for marijuana and for xanax. Steven says someone punches him in the face. . Like rocked my world. Like I had no idea what was going on. My glasses fell off. I could barely see. Reporter: Now, it's not clear who did throw that punch. But eyewitnesses all later confirm that it was not Colin brew. Jones tells police that as he retreats towards his red mustang he's pursued, chased into the parking lot. I thought I was going to die. Reporter: And that's the moment Jones says when he opens the glove compartment and pulls out his Glock .22 handgun. I turn on the flashlight, and I point it at him and I said I have a gun, don't Move. And then -- Reporter: And shoots Colin brew and Nick peering. He was running at me and staring right at me and saying he was going to kill me. I was afraid for my life. Reporter: Jones says after shooting collegein and Nick the rest of the frat guys in the parking lot descend on him, pummeling him on the ground. Jones says he frantically fired in the air just to get those kids off of him. But he shot two more students. I wasn't trying to hurt anybody. I wasn't even aiming at anybody. Reporter: After more than two hours of questioning the freshman is led off to jail, charged with first-degree murder. His trial begins in flagstaff, Arizona a year and a half after the shootings. He pleads not guilty. In their opening statements prosecutors and defense attorneys paint dramatically different pictures of what happened in that Nau parking lot. To the victims the defendant was an assassin emerging from the darkness. Reporter: Prosecutor ammon barker argues Steven Jones was a calculating cold-blooded killer. The question for you during this trial will be what was the defendant's intent when he shot these four unarmed victims. Reporter: It's a question the defense is eager to answer in its opening statement. This is a case about an 18-year-old kid who found himself in a situation where he was surrounded, bullied, threatened, and attacked and did what he had to do to protect himself. Reporter: But the young men who were shot dispute that. Insisting no one threatened Steven. I wouldn't even say it was an aggressive situation. It was a verbal argument from what I could see. The people who say that Steven Jones was just defending himself against a bunch of bullying frat guys. THAs his defense. Never even saw the kid until he The trial lasts almost two weeks, and the testimony does little to clarify what actually happened that night or even how it all started. Then Steven Jones does something rarely done in a first-degree murder trial. Hello. My name is Steven Jones. He takes the stand in his own defense. I knew that if I waited even another split second I would get seriously hurt or die. Reporter: But prosecutors hammer the fact that Steven walked 90 feet toward Colin brew before he says Colin charged him. Even though he told police he was in front of his car. You keep saying to the officers that you were right in front of your car, right? Correct. So each time you were describing that you were just wrong about it. Right? Correct. Reporter: Jurors head out to begin deliberations, and five days later the jury is hopelessly deadlocked. This court is therefore going to declare a mistrial in this case. Breaking news coming in out of flagstaff. They tried but just couldn't agree. Reporter: Prosecutors intend to try Steven Jones again next month, hoping they'll have better luck with a new jury. For "Nightline" I'm Matt Gutman in flagstaff, Arizona.
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