that was the person that was in my home. >> de silva had no alibi for the night of the crime. >> i've never been so sure in my life as a detective that dougwas the right person. >> de silva was arrested and charged with the attempted murder of kaye robinson. >> he said to tell her i'm sorry. i didn't mean to do it. i remember going there, but i don't remember stabbing her. to me, that's a confession. >> but then came the bad news. de silva's fingerprints did not match the prints taken from the blue plastic glass in kaye's home. >> the fact we didn't get any fingerprints that matched doug de silva's from the scene never led us to believe that he wasn't the suspect. because a lot of times, we don't find any fingerprints. >> and perhaps the worst piece of news was that de silva's dna profile did not match the evidence collected from kaye robinson's rape kit. >> dna evidence conclusively ruled out doug de silva as being involved in this crime. it was, almost, i mean, like being struck in the head by a 2 x 4. >> we were extremely shocked. it was like someone had punched you in the stomach. >> this was devastating. the investigators, the prosec