At UC Boulder, The Other Earth Day

Over the years, University of Colorado administration and local law enforcement have tried different methods of deterring people from participating in 4/20. One of these methods, [CU spokesperson Bronson] Hilliard said, was to take pictures of participants and offer a reward to anyone who could identify them.

Hilliard said this tactic didn't work very well and caused some image issues with the administration. The university's primary approach now is to emphasize that 4/20 is not a sanctioned event, but that if people do participate, they should be smart about it.

"What we're most interested in is safety," Hilliard said. "We're not interested in busting people. Possession of less than an ounce of marijuana is basically about like getting a speeding ticket. It's certainly not worth it to risk confrontation with a crowd that size."

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