ASA Fastpitch girls softball ruling

Question
I have a pitcher on my team that has demonstrated a behind the back pitch. She can throw it for a strike regularly. My question, is it a legal pitch? There was a girl who's name escapes me that pitched in division 1 ncaa that was on a show 360 degree softball, and the pitch was legal there. Most umpires say it is hiding the ball and it is illegal and others say its a legal pitch. I just want the rule in writing to show them and for my knowledge also. Any help would be great.

Answer
Hi Keith,

6-3-e  says the delivery must be an underhanded motion with the hand below the hip and the wrist not farther from the body than the elbow.

6-3-f The release of the ball and follow through of the hand and wrist must be forward and past the straight line of the body.

I don't see how an behind the back pitch could ever meet those requirements.

Mark