These are Libertarians (conservatives) leading this action. They are not anarchists. They are not socialists. They are not anti-capitalists. I don't agree with everything for which they stand, but they are completely correct that the U.S. Constitution grants them the right of assembly. Furthermore, that Constitution takes precedence over the Pennsylvania criminal codes cited by the Chief of Police of Pittsburgh. The Chief does not have the legal authority to set aside the Bill of Rights. The actions of the police as shown in the video are fascistic.
Those people were there to give voice to their grievances, to make known especially to the U.S. government that Wall Street bankers have acted in collusion to defraud the American citizenry out of tens of trillions of dollars misallocated to prop up a huge scheme and that lies were told in order to push through the adoption of bailout measures. They want their money back that was stolen from them and is still being stolen from them.
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
That's the First Amendment of the U.S. Constitution. "Congress shall make no law ... abridging ... the right of the people peaceably to assemble, and to petition the Government for a redress of grievances."
All state, county, city, and other laws in the United States are subservient to that. There are no ifs, ands, or buts. If the people are not peaceably assembled, that's different. Those people in Pittsburg were non-violent, non-threatening, and even unarmed. They made their wishes known in very clear terms. Their Constitutionally guaranteed civil rights were trampled by police-state, totalitarian, fascistic tactics. There is absolutely no doubt about that. Even still, they remained peaceful. They were amazingly restrained and thoughtful.
Now, they weren't being exactly Christian; but they weren't being Satanic either. The police following the orders of the bankers, however, were being Satanic. That's obvious.