>> how did carolyn die? >> her death was ruled a strangulation. so things started kind of matching up. ynobe had never been convicted of sexual assault, but in the files the detective read the account of one particularly brutal attack. the case ended up being charged as a misdemeanor, unlawful restraint. it was kristen's. ynobe was the man she says almost killed her. >> i was certain that he had done this before. but at the same time, i didn't think he would do it again. >> the detective called ynobe matthews back down to the station for another interview and decided to pull a fast one with his suspect. telling him he was about to get dna results from the crime scene. were you really about to get it that quickly? >> we weren't going to get it that quickly that day. but trying to get him to believe that we had that information, that we had everything that we needed. i had contacted my supervisor earlier.