I think the police and CPS should be called lickedy split, because you, as the parent ,are way too close to the situation to be able to truly assess the situation in a sane and rational manner. They really should go in there and talk with your daughter, the teacher, and the principal. You need to stay out of it, because, you are probably part of the problem. A Parent, in general, hasnt' a clue as to the wants and needs of their child, you need to leave this up to the professionals. I wouldn't worry too much if your daughter begs and pleads with you to protect her. She's not old enough, or of the mindset to know what is really best for her, and you for that matter haven't a clue. Trust me on this, let the State do their job, and maybe if you are lucky, and you take heed to the pro's, you can get yourself on the radio and exploit your child's tragedy, and maybe, just maybe, someone will throw you a parade for doing so.
Just some words of wisdom, from one fabulous mother to another.