reporter: denita smith probably never saw it coming. one shot, a clean hit from behind. the killer was apparently lying in wait on the apartment s second floor landing as denita walked down the stairs from her third floor unit, said durham police detective shawn pate. there were four apartments on that landing. i think that someone was there pretending they were knocking on the door or fumbling for keys. reporter: so denita probably would have had to walk right past the shooter? probably good morning, how are you, then turn and go down the steps. reporter: bang. and that s it. reporter: denita murdered. executed in broad daylight. it made no sense. her bff edythe says denita simply didn t have any enemies. denita was a light in this dark world. she had a beautiful spirit. she was loving. she was kind. she was supportive.
if you don t ask it, you re not getting it. reporter: investigators had two wildly different stories. he said, she said. who was telling the truth and who wasn t? it was clear we were down to two people. it was one of these two people. and they both had the same allegations about the other one. reporter: there was only one way to sort it out and make sure that denita smith received the justice she deserved. if we can ever prove who was stalking whom, i think we have our case solved. reporter: and soon something would provide that very answer. all of a sudden then the rape allegation happens. coming up she came crawling into my bedroom, hysterical. and i m asking what s wrong, what s wrong. reporter: shannon reports a crime, and this time she says she was the victim. they tested her clothes,
she embodied everything that was positive and about supporting people. reporter: there was no one who didn t like her? right. she was well respected and well loved. reporter: especially by her fiancé, jermeir stroud, who appeared devastated by denita s death. jermeir didn t say anything. jermeir cried. we all cried. he didn t really say a whole lot. reporter: jermeir and denita had met back in college and became the it couple on campus. they had been dating for a few years. and, you know, before i even met him denita spoke very highly of him. reporter: what d she say? like he s a gentleman, he s intelligent. he s active, involved, well-rounded, he s kind, he respects me. he protects me. he s loving. reporter: the perfect guy? the perfect guy. the perfect guy. reporter: he was apparently even perfect enough for denita s cautious mother, sharon smith, who came to trust that jermeir
reporter: as far as detective pate could determine, it all came to a head on christmas eve. jermeir walked into his greensboro church with denita on his arm, and a diamond ring on her finger. he had proposed, and denita was over the moon. she walked into church proud as a peacock, feathers just completely on display, showing that hand to anyone who would look. and shannon was in the back of the church at the time and saw that. we heard that was the first time shannon realized that they were engaged. reporter: shannon s family says the d.a. and the detective heard wrong. the day that that you re referring to, the church, shannon wasn t there. we were there. reporter: less than two weeks later, denita smith would still be wearing that engagement ring, as she lay dead at the bottom of her apartment steps. now, just as assistant district
reporter: as the trial approached, the d.a. facing a circumstantial case with a seemingly credible defendant, offered shannon crawley a deal. plead guilty to denita smith s murder and be sentenced to a maximum of 12 years in prison. denita s mother, sharon, was not happy. what d you say? no. reporter: don t let her off? uh-uh. no. my words were my daughter didn t get to plead for her life that morning, so no. no plea. reporter: she needn t have worried. shannon crawley was not going to take a deal. she insisted she wanted to clear her name and would now take her chances in court. coming up shannon would look at me with this little smirky look on her face like she knew she was going to get off. shannon on the stand. for one he s told me since that he did.