Now this is something that occurred to me, what with our increasing liberalness around Marijuana and the Opioid epidemic, is that safe injection sites should offer free drugs. Treating addiction as a crime clearly does not work, however our criminalization of it has the effect of creating a culture of crime that accompanies it. Canada, as a country, could purchase heroin from second and third world suppliers at pennies per dose - given the costs associated with safe injection sites (needles, nurses, staff, rent, etc) this would be the smallest expense associated with our tolerance of addiction, and would ensure that addicts received quality "medication". Benefits to this would include - lack of crime surrounding both the dealing and trafficking of drugs (how are you going to sell crap drugs when quality drugs are available for free), a decline in overdoses and an incredible reduction in crime related to addicts attempting to subsidize their habit.
Upon the slightest consideration the only objection to this is a "moral" one, in which addiction is perceived as a moral failing or weakness and not an illness - which is clearly wrong - and by changing our thinking we can improve the quality of life for everyone living both with addicts, addictions and in the cities in general. Treating addiction as an illness is the first step towards curing it, and any costs associated with "Free Drugs" will be recovered a hundred fold by the associated reduction in crime.