University Police on motorcycles stand watch at the University of Colorado in Boulder, Colo., on Friday, April 20, 2012. The university closed the campus to prohibit an annual 420 marijuana smoke out.... more 
University Police on motorcycles stand watch at the University of Colorado in Boulder, Colo., on Friday, April 20, 2012. The university closed the campus to prohibit an annual 420 marijuana smoke out. (AP Photo/Ed Andrieski) less 
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Associated Press | Photo By Ed Andrieski
Fri, Apr 20, 2012 9:11 PM EDT