piece of evidence, he locks up. now he s not that little boy i ve been talking to. now he s a man and he understands his situation and he says, i need a lawyer. reporter: just like that? absolutely. reporter: and clammed right up? he locked up tight. he sure did. reporter: also, remember, whoever killed shelley must have had a key to her apartment. there was no sign whatever of forced entry. nathan may well have had a key. and shelley told her mother she was thinking of breaking up with nathan. did she tell him? did he use one of his many knives to get even? is that why the bloody baggie was in his bathroom? the kid, being a boyfriend s got a motive. he could very well did it. he could have very well had a key. he could have very well slipped in there undetected, been in there from you know, she could have invited him in for all we know. did what he did for whatever reason he chose and then left. it was not looking good for nathan. not at all.
her. i did not do anything. yes, you absolutely did. [ crying ] all i want to do is hear the truth. i know what the evidence is going to tell me. reporter: he shoved a photo of shelley, dead, covered in blood, in front of daniel. remember her looking like that? that s your handiwork. that s what she looked like when you finished with her. look at her. don t cover her face. look at her. that s what you did to her. that s what you did to her. that s what her mommy and daddy had to look at. what do you think about that? look at this! look at it! think about the last words she said. think about the last words you heard that say that girl say before she took her last breath. you think about it. how can you live with yourself? take your damn hand away from
your eyes and look at me and tell me how you treat a girl like that. tell me how you do that. i didn t do that, sir. reporter: however, by then, detectives had heard that daniel was not fond of shelley because he felt she was a bad influence on nathan s studies. which wasn t true, by the way. but that s what daniel claimed. and then his friends suggested what might be the real reason daniel disliked shelley because he was jealous. didn t like nathan spending time with a girl. detective ellzey turned up the heat even more. how can you despise a human being that bad? she didn t do nothing to you.
reporter: with few clues to go on, detectives would focus on a small group of shelley s fellow students. had a budding artist designed a seemingly perfect murder? there was the boyfriend, fascinated with weapons. he had daggers. knives. swords. who collects that kind of stuff? reporter: there was the guy always hoping to get her attention. trying to corner her in the hallways at school. texting her on the phone. she s like, he s really weirding me out. reporter: once there was a quiet, little girl in a quiet, little town who liked to draw. she drew the butterflies that floated, quiet like her, around italy, texas.
after the walmart and the trip to white rock lake, he said, he went to visit that friend, jessica. discovered she wasn t home. he said that already. but this time he added one little detail where his friend lived. you get back in your car. where do you go? i went to the falls to go to my friend s house, jessica howard. reporter: the falls apartment complex. that s where shelley was killed. daniel didn t mention the falls the first time he was interrogated. why did you leave that part out? because i was mugged over there, sir. reporter: mugged? and yet he somehow failed to mention that during his first, long session of questioning? coincidentally, while he s at this same complex, he s approached by a black male with a knife who robs him.