I believe him. The voices MUST have been real. After all, he didn't hit any road side bombs while he was in Afghanistan, did he?
PFC Lawrence was moved to a mental health facility for treatment yesterday evening. See the latest AP Story: http://www.google.com/hostednews/ap/article/ALeqM5jCP4Ygk_RBW_r5FGsjAlnqmOPapw?docId=e9530b65a6a14910a4729e3b83006726
While you are at it, read about the death of the chaplain that sent this young man into a downward spiral: http://www.latimes.com/news/nationworld/nation/la-na-chaplain-20101202,0,1891421.story?page=1
So yes, believe that the voices and mental illness are real.