Medical marijuana has been legal in Colorado since 2000, when voters approved Amendment 20. In November 2012 the voters of Colorado approved Amendment 64, which legalized retail marijuana. Since the passage of these amendments, the City and County of Denver has adopted ordinances to regulate, license and tax both medical and retail marijuana.
“The Denver Collaborative Approach: Leading the way in Municipal Marijuana Management.” Denvergov.org. 2017. Web. 28 August 2017.