I very, very highly doubt it'll do anything against your crime rates as most crimes do not involve drugs. Oh, you mean people selling marijuana ? Yeah, that'll still happen because it will be cheaper than in a store because there's no taxation on it. People that sell it here in The Netherlands sell it directly to the stores most of the time simply because there is no tax on drugs of any kind. Making it legal is harder than one might think and i'm sure the United States will find that out quickly.