didn't think jermeir was capable of murder and insisted she didn't even know denita smith. then detective pate zeroed in on the last time shannon was in durham, the city where denita was murdered. >> she says she's never been to durham. i ask her about owning a gun. and she tells me that "i've never owned a gun. i can't stand guns. i'm scared of them." i said okay, i can understand that. a lot of people feel that way. >> reporter: and as for where she was on that chilly january morning? >> she told me she was at a doctor's appointment with one of her children. that was easy to check out. her supervisor was on scene. and she did tell her supervisor that she was taking her child to >> reporter: shannon's story seemed to add up. maybe she wasn't the distraught woman the eyewitness saw leaving the scene of denita's murder, 50 miles away from where shannon lived and worked. detective pate was just about out of questions. and then -- >> an interesting thing