I think both sides were wrong, but the cop was in the greater wrong. He was trying to provoke a confrontation.
1. Pulling over a driver for not using lights is ridiculous. Why even bother? Isn’t there other , more pressing tasks this cop could do? Like actually fight crime?
2. In no way did this woman sound impaired when she was talking. There was no justification for trying to prove she was under the influence.
3. When he gave her the warning, he should have ended the interaction. Asking her if she was irritated was a provocation.
4. When she told him why she was irritated, he made a snarky verbal response in turn.
5. He then asks her to put out her cig, way beyond the time this interaction should have ended.
She then became in the wrong by refusing to get out of the car.The request to get out of the car was out of line, but at that point she should have realized she was dealing with a power hungry cop, complied, and fought this in court. I find it very interesting that the alleged physical altercation was out of camera range, which I suspect was a deliberate move by the cop. So now, after seeing this cops prior behavior, I would not believe anything he said.
To your points...
1. It was a valid stop for a valid traffic violation. Cops stop cars for that all the time because it is the law. Many accidents occur because people fail to signal.
2. Nobody ever said she was under the influence, but her history suggests drug possession
3. He didn’t ask ‘if’ she was irritated, but rather ‘why’ she was hostile. This was a valid question to understand her hostile behavior, which started from the beginning of the stop.
4. Both should have been more respectful and polite
5. In TX, asking her to put out the cig or get out the car are both appropriate. We don’t know the cop’s motivation yet, but he may have had a valid reason. He may not have. Either way, her refusals gave him a valid reason since her refusals were in violation of the law. She was still detained.
6. The physical altercation could be out of camera deliberately (we don’t know yet), but it could also be because she was fighting and resisting him. People that do that generally don’t stay in one place. They will pull away from the cop, forcing the cop to give chase. The cameras don’t move so if the suspect moves, the cop has little choice, but to move also. We don’t know the details yet
7. The cop was rude, which may be against policy, but not illegal. Her refusals were illegal, which led to her arrest so the fault lies with her.
It's not. Classic broken windows maneuver. Criminals tend to figure, in for a penny, in for a pound. Cops catch a ton of criminals with warrants out for their arrest while stopping them for minor traffic violations. That's why traffic stops are so dangerous for cops, yet so vital for catching perps.