Here is information on this from the Colorado Department of Public Health and Environment at
Medical Marijuana in Colorado
Where can I legally use my medicine?
No patient shall: Engage in the medical use of marijuana in a way that endangers the health or well-being of any person; or engage in the medical use of marijuana in plain view of, or in a place open to, the general public. Law enforcement has informed the Medical Marijuana Registry of the following: Any place outside of the patient’s home is considered public. “In plain view” also includes the patient’s yard or garage if that patient can be seen using their medicine by neighbors.
This website is a great source of information for mmj in Colorado.
mmjmike