Until I see a picture of a person in a Ron Paul shirt with handcuffs, this can just be considered being in the wrong place at the wrong time.
Pfft. If that's all they need to fool you it'll be easy. Police routinely infiltrate protest groups to cause the disruptions. I doubt that's what happened here, but if Paul starts doing /really/ well, and things get too "hot" for the rulers, they will definitely resort to that. It is routine.
-Jeff