[moeris]

Well, if someone goes to prison for a relatively harmless drug, they're more likely to turn to hard drugs.

For hard drugs it can probably help centers do things like safe injection sites. Legalization also means you can regulate. That can help in a lot of ways: making drugs safer, mandating that done portion of proceeds gives towards prevention, etc. Addicts will be less afraid of seeking medical treatment if they know they won't be in legal trouble. (They wouldn't anyway, but I've heard a lot of people are paranoid about this.)

Anyway, I don't have any facts or figures. But it seems reasonable to me that legalization could, in some cases, help.