We need a "Photograph a Cop Day" to take place worldwide. Everybody and anybody, using everything from cell phone cameras to large format monsters. Take a photograph of every police officer seen and post them all on Flickr, Facebook, Photobucket, etc, etc. Don't stop taking photos as the police object and try to put a stop to it. Motor drives on SLRs and such - hammering away, a hundred photographers taking the same photo of the same cop, and all happening at the same time in a thousand places around the world.
Remembering that the police are not the enemy - they enforce the law as given. But they will not be happy, and the fallout will roll back up the chain - to the people who are doing this in the name of our mutual 'safety'.
It has to be done, but to be effective, it must be done out loud and en masse and worldwide.
And yes, some people will go to jail. Hope so, anyway.