Last night, as the G20 had wrapped up, I was about a mile away from the Schenley Plaza "protest," monitoring police bands and getting messages from people at the site. A few observations:
1) There was no formal "protest," per se. A group of people had decided to assemble on the plaza to call attention to what they considered to be unnecessary brutality by the police earlier in the day. It's the sort of thing that happens all the time.
2) Police arrived in masse. Oakland had been witnessing a show of force for the past few days (I know: I regularly drove past long lines of cops in riot gear and watched an apache helicopter fly low over my house.) At least some of the cops were not from Pittsburgh. In fear of a repeat of Seattle, the local "authorities" (and it find it increasingly difficult to use that word) brought in and deputized police from across the country. I know some were some Miami. The scanner reported when a busload of Chicago cops arrived on the scene.
3) A crowd emerged to see the show. The plaza is across from the university library, and a block from freshman dorms.
4) The vast majority of the vandalism (broken windows) in the area was traced back to a single anarchist from California. (It was clear it wasn't a local when he hit the student's favorite diner. I suspect there was student cooperation to find and turn him in, but can't prove it.) He was in custody before nightfall, and before any crowd assembled.
5) A sonic weapon was used: a Long Range Acoustic Device (LRAD), similar to those deployed in Iraq, on ships, and during Katrina. Big-city police departments have been purchasing the LRAD, but this is, to my knowledge, the first time one has been used on a crowd inside of the US.
6) Local tv news was reporting from the scene in the early phases. It was all great theater and it was occurring during the regular 11 pm news broadcast. However, just before the riot control gasses were brought out, the local stations cut away, never to return.
7) On the scanners, before switching to tac frequencies I couldn't monitor, there were repeated references to initiating "hammer and anvil."
8) Crowds were told to disperse, but at the same time were given no place to go. The cops were quite thorough in blocking potential exits. Some people were trapped on open stairwells, with police blocking the top and bottom, while the gas passed through.
9) Some of the cops were very professional. Some of them acted like thugs. One of the high points was when the campus cops refused the outsiders admission to the dorms. It didn't entirely stop them, but it slowed the city (and other) forces and gave people a chance to calm down.
10) Cops were very aware of what might get to the news. I monitored pursuits being broken off for fear that they would be witnessed by news crews.
11) Although people have begun to be released, the police are holding their property. There is some concern that cameras and cell phones will be empty when (and if) they are returned.
12) Most of the city is glad to just get back to normal. Some people are very, very pissed.