An MP buddy when I was in the army told me the simple way to get someone out of a chair or car - take a bic pen and place the click end behind the person’s earlobe and your thumb on the front side of the earlobe and squeeze. A second or two later and the person won’t be able to get up fast enough. Doesn’t require a struggle and no one is hurt beyond a pinched ear. The cop could then either have led her by the arm or put cuffs on. He wouldn’t have been fired and it would have been far more appropriate than his method.
I was at a restaurant late one night and some people came in that appeared to be from a wedding party, and a couple of them were pretty drunk. One got into an argument with the hostess and the manager and was just being an ass. Suddenly I hear him yelling and cussing, and I look over and see another man from the same wedding party, about half his size, has him by the ear with a Gerber too and headed for the front door. He returned to applause from just about everyone in the place.