He could have nicely asked for answers while holding the citation book and the pen and reading the section above the signature line that says 'your signature is NOT an admission of guilt'. At the point he said, "I'm not going to sign this", the nice coversation was concluded.
I'm surprised the cop didn't just shoot him. He's got the badge and that's all he needs, right? The guy failed to fall all over himself the way he should have...I'm sure he's just lucky that he was only Tased.
In your average fascist dictatorship, you're absolutely right - subject closed, you're on your way to the Gulag.
In a democracy, you'd think that citizens should be treated better. Had this particular cop spoken to that young man (which is what he is, not a "punk" - you must have issues with younger men..) and calmly and professionally explained that he would be subject to arrest if he didn't sign - and even better, included the basis for the charges as the young guy asked, he wouldn't have had to Tase anybody.
But I suspect that cop was itching to try that thing out anyway. He should be ashamed of himself and so should the state of Utah.
If all you can see is a country loaded with punks that must read signs or else, you really don't enjoy life much, do you?