According to data from the Centers for Disease Control and Prevention (CDC), 4,102 people died as an unintended consequence of heroin overdoses in 2011 (the most recent year for which data are available), compared to 2,789 deaths in 2010—a 47 percent increase in a single year. Heroin overdose deaths had risen somewhat over most of the preceding years (except for 2009-2010, when they actually declined), but the general upward trend had been more gradual, so these numbers come as a wake-up call.
Nora s Blog What Can We Do About the Heroin Overdose Epidemic National Institute on Drug Abuse NIDA
See, it isn't necessary to shoot it anymore. Hasn't been for ten years. So, kids start out snorting it and then move on to shooting it.
Legalization of marijuana did not remove the black market or the additional crime that goes with it. That was about someone wanting a piece of the pie.
Harm reduction method does impact the harm to society. Needle exchange programs work. Even areas where they have prescribed heroin for people that cannot manage to kick it has shown progress.