Cannabis (or marihuana) is one of the most widely consumed psychoactive substances in the world. According to the United Nations World Drug Report, 183 million people, or 3.8% of the world’s population, used cannabis in 2014. Its cultivation was also reported by 129 countries. Cannabis is subject to the United Nations System for International Control of Narcotic Drugs and Psychotropic Substances (hereafter “drugs”) and is the most widely consumed of all the drugs. According to that control system, cannabis is among the substances with the strictest legal status; they are the most prohibited, supposedly because of the harm they cause and their lack of medical usefulness.