Excessive or appropriate use of force?

What do you think? A 12 year old girl is seen striking an officer in the process of resisting arrest.

I see a police officer, instead of helping his fellow officer wrestle this girl down, lets him handle her while he searches for an opportunity to shoot her. At the point that she's on the ground and still struggling, he shoots her close range - you can see the beanbag bounce off her and travel 7 feet towards the Max car.

It so happens, the officer firing the beanbag at this girl, was also involved in the arrest and subsequently resulting death of a homeless man.

Once you strike an officer, all bets are off; you've allowed the officer to escalate force. But, the question remains, is it appropriate to use a beanbag up close on a 12 year old girl, even if she strikes an officer? Of course, he doesn't know that she's 12 years old, but it bothers me that he walks around after she's on the ground, looking for the right opportunity to shoot her. I'm not sure he needed to use the beanbag shot to subdue her, especially since she was already on the ground. But at least he didn't shoot her in the chest or abdomen.