Let me get this straight. I wasn't there, but I'm trying to figure out what happened. Based on what I see in this thread, this is what happened:
1. Drunk guys/girls are fooling around and dare each other to use the opposite sex's bathroom.
2. Drunk guys accept dare, and do their business in women's bathroom.
3. Someday in women's bathroom feels uncomfortable, notify police/security at party what is going on.
4. Police enter women's restroom and ask guys to get out immediately.
(now here is where events are less clear. this will be sorted out in court, but here is my best guess)
5. Guys in bathroom (being drunk) semi-laugh off police request and are hasty to comply with the order to leave the restroom. They don't seem themselves as doing anything wrong and take police request lightly.
6. Police have short fuse (as they should) and forcibly remove guys from restroom. Sound like the police really had to drag these guys out. On the way out, guys are dragged/pushed against wall (which I don't consider unreasonable if these guys didn't immediately cooperate).
7. Once they are out of bathroom, Mike sees these guys getting dragged out. He thinks police are acting out of line (***EVEN THOUGH HE HAS NO IDEA WHAT WENT ON IN THE BATHROOM***), and speaks up (perhaps in a semi-threatening tone). He also moves toward the officers.
8. Police feel need to subdue Mike. The quickly bring him to the ground. Mike, who is not sure why he is being brought down gives them lip and resists (sure, he didn't run or say "f*** off", but he probably didn't fully relax, shut up, and let the police cuff him which would have been the smart choice).
9. Police taze Mike to get him under control.
If this is in fact what happened. I don't think the charges are unreasonable. Mike should not have cried bloody murder and moved toward the officers, especially if he didn't know what went on in the bathroom. Perhaps the police dragging the guys out of the bathroom was legitimate and justified (it probably was, IMO). Particularily when they feel threatened or someone is breaking the law (guys in bathroom) the police have ultimate authority to enforce the law, and anyone who stands in their way [erhaps deserves to be tazered.
Stop bringing out hypothetical situations about the police pulling you over for 40 in a 35 zone and then beating the s*** out of you. That just doesn't happen (unless you give lip, run, or are packing heat). And if I ever was in the situation, I would be smart, comply with police instructions, and get off with a warning. What you YOU do?