smoking gun, getting this photo of diana lovejoy? ion. there is a lot more to be done. >> reporter: sergeant ernst's team searched for more evidence in diana's home. >> we were able to locate the clothing that she was wearing when she purchased the phone. >> reporter: police had enough to arrest diana and bring her in for questioning. at first, she denied any involvement in the shooting. what is her alibi? >> that she was at home all night long, she never went out. >> reporter: and police realize she might be telling the truth about that, just because she bought the track phone, didn't mean she was at the crime scene. because diana was most likely not the person lying in the grass in camouflage with a rifle, fair to say? >> yes. >> reporter: did you ask her if she hired someone to kill greg? >> yes. no, i did not. >> reporter: detectives pressed her and diana told them something they didn't expect. >> she starts to describe her relationship with her shooting instructor. >> diana told police her instructor's name, weldon mcdavid. >> he