when sergeant jess watkins took over the cassy farrington investigation, he came to believe what herdence tying him to the crime scene, could prosecutors prove it? here is keith morrison with the conclusion of "suspicion in silver city. " >> it was the day the brooks family feared they'd never see, brad farrington on trial for murdering cassy. >> i never thought we would get this far. >> too far? the prosecutor's opening argument was a warning to the jury -- we don't have a lot. >> no one saw the defendant enter cassy farrington's home. no one saw the defendant strangle her. >> no. and there was absolutely no evidence from the crime scene to help their case. the prosecution didn't even call the now-retired detective, jose sanchez, as a witness. >> what we were rather brief on was the scene. >> that was a weakness, actually. >> well, i don't know if i would call it a weakness, but it wasn't a strength. >> you should be in the diplomatic corps. >> well, there just wasn't anything there that was terribly useful, so we showed the scene so the jury could see, you know, this is where it ha