billy lee. >> why did you choose to focus on mr. lee? ow the defense was using sanchez to raise doubt about who the real killer was. >> there's a lot of smoke here but no fire. >> mudles it up. >> and that, i believe, was the defense strategy, that if you have enough of that, then the jury won't see through it. >> the jury retired to consider. >> oh, i was so nervous, i just paced up and down the halls, in and out. >> four hours later, they were called back into court. >> has the jury reached a verdict? >> we have, your honor. >> the defendant shall please rise. we find the defendant, bradley farrington, guilty of first-degree murder. >> when they announced their verdict? >> there was a lot of tears, a lot of sighs of relief. one of the deputy attorneys says, thank you for not giving up, thank you for pushing. and i said, how could i? it was my little girl. >> brad farrington was sentenced to life. no parole for at least 30 years. he's filed an appeal. cassy is but a memory now, and so, her parents remember their way through their pain to