Oh, don't worry--once Mitchell and his lady friend get lawyered up, we're really going to see a sell job by the defense attorneys. I do expect Mitchell to attempt an insanity defense.
I think an insanity defense would be risky. (Yes, clearly he is not normal mentally, but the key is whether he knew taking her was wrong.) I think all he has to do is claim she asked him to save her and take her away and she became obsessed with him, etc. Then, a sarcastic defense lawyer can ask whether anyone on the jury has had much success getting their teenage kids to do something they didn't want to do, for nine straight months. He can say, I can't even get my teenagers to brush their hair; how can this poor man have controlled this girl so completely? And then he can introduce medical and other evidence showing she was not in some detached psychotic state when she was "recovered."