But that begs the question that criminal prohibition of drugs like heroin actually reduces their use. If proponents of bans are responsible stewards of liberal

But that begs the question that criminal prohibition of drugs like heroin actually reduces their use. If proponents of bans are responsible stewards of liberal society, they not only have to show that the problem is greater than the loss of liberty, they also have to show a causal link between denying that liberty by force and actually solving the problem. Everybody agrees heroin is bad for the individual and for society, and that it should go away. What isn't clear to me is that putting users in jail and creating a hugely competitive profit incentive for violent gangs is actually effective towards that goal. With heroin already illegal we see that a given portion of the population uses it anyway, so how much of the population do we think is not using it solely because it is banned? How does this compare to purely medical intervention?