Manimal... your awesome. Nyan cat is just the way to go.
I think in this situation the officer is most at fault for escalating this situation. There are much better ways of being persistent and getting what you want... which in this case is I.D.
He was trying to create a situation. Trying to get this arrest. I suspect prior involvement between the man arrested and the cop who mainly instigated it.
In either case, this man, with his evidence on camera, very well could have fought this in court on the basis of his arrest. If he just eventually cooperated. But, he refused because it is his right. The police saw his refusal as resisting arrest and became even more aggressive.
Also, for the whole "Why are you nervous? Your legs are shaking!" Umm.. you just fucking tazed him four times you, douchbag. You'd be shaking too!