Weed flag (credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
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Denver 4/20 Rally On May 21
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Denver 4/20 Rally On May 21
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Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
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Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
(credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
Smoking marijuana (credit: JASON CONNOLLY/AFP/Getty Images)
Denver 4/20 Rally On May 21
People attend the Denver 420 Rally, the world's largest celebration of both the legalization of cannabis and cannabis culture, May 21, 2016 in Denver Coloroado.
The western mountainous Colorado is one of four US states along with the District of Columbia that has legalized the use of recreational marijuana. / AFP / Jason Connolly (Photo credit should read JASON CONNOLLY/AFP/Getty Images)