That's great news. Now, although you may not understand this in light of my previous posts, try to understand.
The child may not be prosecuted and that's not necessarily a bad thing. The point is to not only make him aware that his behavior was wrong, but that there are consequences involved and that the behavior MUST change.
If that occurs from this, then one/half of the battle is won.
Your daughter also needs to realize that she has something to be proud of. It's called guts. Many girls her age protest but do nothing. I'm proud of her for telling you and for standing her ground.
Get her as much help as you can in dealing with this but the most important thing is that she knows you'll always stand beside her. And that saying NO! is just fine.
As for the school and the police department, wait until you have the results of the investigation before busting their asses. But regardless, if I were still in the newspaper business, I'd be at the next school board meeting asking why this was not investigated BEFORE a complaint had to be made at the county level. (hint

)
As well as at the police chief's office with the same question.
Congrats. You have a gutsy daughter you should be proud of.