Funny how a viral video suggests one thing and the body cam footage suggests another. Now it seems that other than the part where the officer forearms her on the back (neck and shoulder) while she resists arrest the officer's actions were completely appropriate. She was being cited for underage possession of alcohol (not drinking) but refused to cooperate or even give her name.
http://abc7chicago.com/watch-police-in-nj-release-bodycam-video-of-beach-arrest/3543577/