on and started traveling it was nowhere near isaiah hagan. in fact, he was in a different county. so he could not have been pinging off the same tower that she was. >> reporter: which according to the defense meant someone else had to have halee's cell phone. but the prosecution insisted isaiah had the phone all along. >> it looks like it powers back up at the soccer field, but we've since come to the theory that when you power your phone up, it hits on the last tower that it was on when it powered down, and so, that explains the reason why it looked like it was traveling. >> reporter: is that exact science, or is that the theory? >> that's a theory. but we have found absolutely zero evidence that there was anybody else involved other than isaiah hagan. >> reporter: the prosecution and the police, they believe that she was shot before isaiah left the soccer field, that his alibi doesn't hold up because she was already dead. >> well, that's hard for me to understand because there was testimony by the coroner that he could not determine a time