>> reporter: and that wasn't the only thing the witness noticed, says assistant d.a. david saacks. >> he remembers a patch or some kind of something, you know, on the shirt. >> reporter: a patch like on the uniform shannon wore as a 911 dispatcher. and there was more. investigators discovered shannon clocked in at about 10:00 a.m., some two hours after denita smith had been murdered. more than enough time for the 55-mile drive from durham to her job at the 911 center in greensboro. so police obtained a search warrant for shannon's house. >> and we do find greensboro communication 911 center uniforms. and they are exactly as described by the maintenance supervisor down to the color of the patch and the shape. >> reporter: you find a gun? >> no gun was found. no bullets were found. nothing incriminating other than that. >> reporter: and then came this.