Well, I may be forced to change my position on legalizing marijuana. This is the first set of evidence that I have seen actually collected by a reputable news organization. I had to replay the Portuguese data on heroin reduction twice, then reconsider the data on Colorado, and consider that the Colorado data is incomplete and that it is too early to tell. The increase in trafficking from CO through to St. Louis MO is up, but it is too early to tell the long-term effect.
It is about 16 minutes, but well worth the viewing: