insanity plea to shorten his sentence to 3 to 5 years. >> so now let's turn to the appeal of amanda knox. nbc's keith miller is live for us in italy with the latest. keith, what can you tell us about a key witness apparently taking the stand in her case? >> well, a remarkable session in court today, alex, where the key witness was called back to the stand. this is an appeal hearing and where he was the man actually who said he saw amanda knox and her former boyfriend at the scene of the crime at the time that meredith kircher was murdered and sexually assaulted and that was within amanda knox's apartment. it turns out he was asked his address and he replied prison. he's in prison on drug charges. they asked him, were you on drugs that night that you claim to have seen these people? he said he was on heroine.