Below is an aerial view from Google Maps. The red arrows denote where and in what direction the union supporters were “parading”. The light green area is where the Scott Walker supporters were.
Police allowed a very narrow access to that area and union supporters would come in and yell “kill the bill” for a while, then the Walker supporters would shout “pass the bill” in return, then the union supporters would leave for a while.
Gateway Pundit linked. Thanks Jim!