Its obvious the cop was just doing his job. Who is to say that she couldnt have pulled out an assault cane, or a high capacity wallet, with enemy suppressor ID cards in it.
it sure looked like it to me. way excessive imo regardless of what she might have been doing - unless she pulled a weapon (which I don't think is what happened).
He could have marched her to the office with his weak hand.. Spitting or not, it was an abuse of authority and hopefully this cop isn't involved with any type of school security again