I see him charging her and shoving her back into the corner where he can get ahold of her and put her down on the ground for control. The “punches” do not appear to be very powerful to me because of the weird angle that they are thrown from. Perhaps some martial artist can talk about that.
I have become very skeptical of videos that are do not have context.
The fact that this young woman had no serious injuries indicates to me that he did not “drive her head into the wall”, and did not “punch her in the head”. If he had “punched her in the head” with any force while her face was in contact with the concrete, he would have likely broken facial bones or teeth, or at the minimum, caused severe bruising. My guess is that he hit her between the shoulder blades.
The excuses some people make for cops are just unbelievable. Listen to yourself. "He didn't hit her in the head in only hit her between the shoulders!". So, what excuse you do think he had for hitting her at all when she was down and under control? BTW, he did drive her head into the wall and did smash her into the concrete. He didn't hit he when her head was on the concrete because he had her head pulled back by her hair,and it sure appears he hit her in the back of the head twice. She didn't steal a car, it was her mother's car, and even if she had stolen a car she shouldn't have been treated that way.
As for the dumb ass that thought she was putting up her dukes, he had better look at the video again, she was cowering in fear and backing away from the officers assault. This guy was a total frickin' jerk and deserves more than 4th degree assault charges to be filed against him.