Here is one idea to consider, because they will try to discredit us.
“Plants have already happened, just not organized ones. Regardless, perhaps organizers (or attendees) need to have a few signs that say “Liberal Plant, not a REAL TeaPartier” and be on the lookout for these double-secret spies. When one is found, then pull out your signs and stand next to the plant. No violence or physical actions, just isolate and embarrass.”