Maybe the police were shown the same training as in this military exercise where the army was given training in 'urban warfare' using U.S. citizens as models, despite the Posse comitatus act which forbids use of the army inside of american borders except in a defense role. Or maybe they just didn't want them harshing on the mellow of the love parade. When I walked around the Love parade, several kids were selling expensive brownies with green leaf decorations on the label, but I concluded that if they weren't reactive, the ravers couldn't really complain to the police.
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