I think it just escalated. The cop yells 'Whoa whoa whoa you can't cross here' and the girls say "@#$! @$%" and keep on going and now, he gets offended and wants them to stop for their blatant disrespect for the law, and their continued antagonism escalates the situation. Had they just said "I'm sorry officer we shouldn't have crossed illegally, our mistake" It would have been done with, right there most likely, but apparently these girls weren't bright enough to make the appropriate decision.
Spending a few moments of their time talking to the officer in a respectful and apologetic manner and they would have been on their way.
I just don't get it.
How can anybody think that struggling and/or fighting with a police officer will get you anything but more trouble?
Seriously, what are in these people heads? What made this girl think that her actions were helpful to her in any way?
Is she just THAT stupid? Did her parents fail her that utterly?
If I was the officer I would have put up with that for all of 10 seconds and gotten out the tear gas or stun gun. I think he was in the wrong struggling as long as he did with her.
The idiot who was saying "really?" is another total moron. You aggressively put your hands on an officer expect to get hit/shot/tazed/sprayed.
I have had run ins with officers over the years. It has always been my policy to make their life/job as easy as possible and nine times out of ten they were quite cool back. (let me smoke a cig. etc, etc)