a stationary rally How stationary do you have to be? Stand to attention or you get busted ? A right to bear arms, but no right to move legs...

But why do they think that a crowd standing in one place is less likely to get out of hand than one shambling along in a parade? It could work the other way, with people getting more chance to get each other worked up.

Of course, that might be the idea. Remember, if anyone starts urging people to charge the cops and break through the cordon, the chances are they will actually be agents provocateurs.