Colorado’s original medical cannabis initiative, Amendment 20, was a citizens’ initiative that passed in 2000. It amended the state constitution to authorize patients to use and possess up to two ounces of medical cannabis, cultivate up to six plants (three mature, three immature), and be assisted by a caregiver. Colorado’s second medical cannabis law, the Colorado Medical Marijuana Code (C.R.S. 12-43-101 et. seq.), was enacted by the legislature in the summer of 2012 to establish a dual licensing mechanism that regulates Colorado medical cannabis businesses at both the state and local level. Colorado allows local governments to adopt regulations regarding medical cannabis businesses and caregiver conduct, which has led to the uneven application of the law. In addition, the Colorado Medical Marijuana Code permits various state agencies to continuously enact new regulations for the medical cannabis community. 


In 2016, the legislature passed two bills pertaining to the medical cannabis program. HB 1371 created protections for children and their parents by eliminating any government-directed punitive response for possessing and consuming medical cannabis on campus, and by prohibiting the use of a minor’s patient status as a reason for denying that child admission into a school. SB 40 extended ownership rights of cannabis businesses to non-Colorado residents. 


In 2017, SB 192 was passed, allowing for delivery of cannabis and single-instance transfers between adult-use dispensaries and medical dispensaries. The passage of SB 17-017 added PTSD and other stress-related conditions to the state’s list of qualifying conditions.


In 2019, under the leadership of Governor Polis, the medical program saw many needed improvements related to qualifying conditions, testing, and product formulations. Thanks to further changes, minor patients can now receive cannabis in schools, and minors can have each of their parents be a caregiver. Separately, the program added autism and any condition for which an opioid could be prescribed as qualifying conditions and began to allow delivery.


In Governor Polis’ first year in office, he signed into law measures permitting cannabis delivery to medical and adult-use consumers from licensed retail storefronts, as well as approving legislation that authorizes cannabis hospitality spaces. Under the new law, medical and adult-use retail facilities may permit onsite consumption of cannabis products subject to local government approval. The law also allows retail food establishments to apply for cannabis hospitality licenses also subject to local approval. Governor Polis also signed into law a bill that adds autism spectrum disorders to the list of medical conditions eligible for medical cannabis treatment. Not all of the state's 2019 reforms were positive, including a new law setting limits on the amount of medical cannabis products that a legal retailer may sell to an individual in one day. For flower, the limit is two ounces, for concentrate, the limit is 20 grams, though the law allows a physician to provide an exemption to the limits.