Dozens of people stand scattered across the lawn at Eden House Co-op on the night of Friday, Aug. 29, enjoying one last hurrah at the start of a new school year. Some chat with friends or kick back on a pair of couches facing the road. Others filter into the packed house, where bands play to a jovial crowd. Suddenly, police cars wash the house and all of its guests in hues of blue and red. Plastic cups drop to the ground in a resounding clamor.The party is over.

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