amri you've been doing this for a long time he thought he was smart and left dna at the crime scene and hear from source they still have defensive wounds that may have dna there. is that a slam dunk for prosecution if they can match that dna to him? >> well whenever you have dna evidence you're always looking to see what is the item left behind and you can come up with an innocent intlangs a rape murder, you know perhaps person will claim he had consensual sex and somebody else killed victim and in this particular situation you've got a knife sheathe left behind according to the affidavit, and that's a difficult thing to explain when you couple that with evidence that we're talking, the car and phone and trail of evidence both before, during and after the crimes. lawrence: yeah. i want to go to you, so what if this suspect says, hey, my knife was stolen. i was not there. you've got the wrong guy there. is a possible in a court of law? >> sure it is possible but here's the deal there's nobody else's dna on the neigh explain you being in the neighborhood 12 times before the murder, explai