Considering the road and traffic conditions visible in the video, the only conceivable justification for a 40mph daytime stop is revenue enhancement for the 400 person ----holes that that road passes through.
I don't see traffic safety, I see armed highway robbery.
The SUV clearly passes the cop...so it may have been a speed trap of sorts. The driver kept asking what he did wrong.
Under color of law. That's why they're called "speed traps."
If you look that sign was in a temporary sign in a construction area.
The speeder was mouthy.
The cop handled it poorly and could have deescalated the situation. Even when it got to the point where he refused to sign the ticked. The cop could have told him the possible consequences. That could have deescalated it right there.
Even if the guy still refused to sign it the cop has the option of arresting him or not.
There was no reason to arrest the guy anyway. He had his wife and kid with him, and was obviously not a threat or danger to anyone.