They are unarmed and alone in their resolve.
Do not make more of this than it is. They are not the enemy, they are us.
Verbal warning is not sufficient enough to justify action. They are not allowed to use a public address system and therefore THE AUTHORITY isn't either. These citizens already know their movements are out of the 'norm' for the park and are using a trusted method of our government to express themselves. Verbal warning DOES NOT justify actions against citizens ALREADY resolved to be heard and respected !
Don't even think about it. It will be noted to be open hostile action against innocent civilians expressing their right of assembly and speech. It will not be viewed as law enforcement so much as OPPRESSION.
