reporter: greer also claimed rebecca had been sexually assaulted with a knife prior to her murder. the expert testified a steak knife found in the bedroom had we are blood on the handle. that s nowhere in any of the sheriff s records. they never considered that. reporter: the defense called a forensic technician who testified she did find the blood on the knife and with it a simple explanation. a recent cut on rebecca s right hand. when greer asked her if it could have come from a sexual assault? i didn t see any evidence of that. reporter: no evidence, a point the defense hammered home. no fingerprint evidence that was identified or directed towards adam shacknai. of all the items i tested, he was excluded on all items. reporter: adam s brother, jonah, took the stand. he called rebecca s death unfathomable, but said adam was not responsible.