Not in Chicago, perhaps, but I was in Philadelphia during that period and watched first-hand as some of Frank Rizzo's crew beat a group of totally innocent black men to a bloody pulp. When the onlookers that gathered protested, the police attacked them too.
http://en.wikipedia.org/wiki/Frank_RizzoRizzo joined the Philadelphia Police Department in the 1940s, rising through the ranks to become Police Commissioner in 1967. He served in that role during the turbulent years of 1967 to 1971, garnering a reputation as a tough, hands-on Commissioner.
One of the most notorious moves by Rizzo's police officers were the raids on the Philadelphia offices of the Black Panther Party on August 31, 1970. The raids took place a week before the Panthers planned to convene a "People's Revolutionary Convention" at Temple University. As pretext, the police used recent killings of two cops (one incident was the August 29, 1970 shooting of Fairmount Park Police Sgt. Frank Von Colln), which were not connected to the Panthers. Rizzo forced the arrested Panthers to strip and stand--some in their underwear, some completely naked--in front of the news cameras. The picture ran on the front page of the Philadelphia Daily News, and was seen around the world. <1> <2><3>
In other respects, Rizzo was also not a typical commissioner. He sometimes quarreled with the city's mayor, James H. J. Tate. He was boisterous and brooding, particularly to media. A biography of Rizzo, with an introduction written by future police commissioner John Timoney, recounted: "Of one group of anti-police demonstrators, he is reported to have said, 'When I'm finished with them, I'll make Attila the Hun look like a fag.'" A female reporter who covered the Rizzo years, Andrea Mitchell (now of NBC News), recounted routine brutish behavior as part of a broad pattern of bravado.
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