No, it is not fine. The Sergeant acted badly.
But, he did not stick a gun in the Open carrier’s face.
The threat was implied, true. But we have seen far worse.
The Sergeant was wrong. He should be disiplined. Training should be done at the Sheriff’s office.
But police are not superhuman. They make mistakes.
Should Sergeant Singer be made an example of?
That is what we are doing on this forum.
I guarantee that Sargeant Singer is already regretting his mistakes that day.
When the same considerations are applied to all regular law abiding citizens attempting to do the right thing, and happen to make a mistake, then and only then will I entertain your thoughts that somehow because he wears a magic blue costume that he is ABOVE THE LAW, if it is an Honest Mistake.