Another participant recorded the incident with a handlebar cam. She gave me the recording and offered me advice on how to fight the charges.
I mean, we're both smart people. Surely we agree that http://www.youtube.com/watch?v=2aT9p36fgHU#t=3m35s indicates the police can do whatever they want, and nobody really cares except the victim.
And there's really nothing to do about it, or any way to change it. Nobody cares about protests except the protesters.
I wish it weren't that way, but, given that things are that way, then why bother fighting?