mr. mccowen then stated, it could have been me. >> it could have been me. >> it could have been me. >> sould have been me who h with chst bec it was his dn >> some of the strongest evidence against christopher mccowen is his statement. i mean, he denies knowing her, and then his semen is inside her. i mean, hello? and then, his statement gets more and more incriminating. >> in his statement to police, chris mccowen first says that christa asked him to help dispose of a christmas tree. >> mr. mccowen explained to me that he had had a discussion with christa worthington that evening in that house about getting rid of the christmas tree. >> that friday night, is that correct? >> that's correct. >> mccowen's statement to the police progressed to the point where he admitted that he had sex with christa worthington on the living room floor. >> his response was, i [ bleep ] out of her. i don't know. >> is that a direct quote, sir? >> yes, it is. >> he changed the story, and introduces another person, a friend of his that he would socialize with. >> he goes on to say, i wasn't the only one there.