I don't think the defense will try to pin this on any one person. I think they will allude to the fact that many other people had the motive, means, and opportunity to do this as well. For example I think they will try to bring in Roy Kronk's ex-wive's testimony to try to implicate him, with Cindy they might say she was the last person publicly seen with Caylee, etc. I think they will go right on down the line w/either all or some of Casey's ex-friends and associates to try to create reasonable doubt. I don't think it will work, but the defense might try it. If they don't try to throw someone under the bus, they only thing they have left is to try to dispute the state's evidence. Either way, they really have no defense. It will be interesting to see what approach they take at trial.