Of course, Oxycodone is legal with a prescription, but that’s a distinction without a difference, as it was illegal for my brother to buy, possess, and presumably sell from time to time. His addiction existed in a curious demimonde wherein the whole treatment and rehab and recovery cultures attempted–I emphasize, attempted–to ignore the plain fact that the disease they were treating, attempting to treat, was a crime, and although making it not a crime might lead to more use, it might also lead to more recovery; it might lead to more regular doses, less adulteration with other substances. It might have meant that my brother didn’t have to die in a cheap roadside motel room after a late-night visit to some dealer’s ramshackle house.
The benefits would outweigh the costs, but drugs are immoral.
UPDATE: People (rather than moral philosophers) don’t have internally consistent and complete belief systems with which they determine what is moral and what is not. Subtracting the costs from the benefits — even if you stick to the costs and benefits that are obvious to everyone, i.e. doing economic analysis, tells you what is right or wrong. Often times, disagreement about morality is just one side or the other ignoring an obvious, at least once its been pointed out, benefit or a cost. You’ll notice that pointing an obvious cost or benefit doesn’t usually end the disagreement. The next move, generally, is to criticize the size of the costs or benefits. In other words, then the argument is no longer over morals, but over empirics. This supports Bryan Caplan’s contention that you don’t need morals to have a normative debate.