States, one by one, began legalizing marijuana, back in 2012 with Colorado leading the way.  It was sold to the public as a way to unclog the criminal justice system, bring tax revenue and strong regulation, which would ensure quality.  In truth the record shows that illegal shops have grown in number even in states with legal shops.  Take New York state.  In New York City itself there are 140 legal shops and 8,000 unlicensed dealers who can undercut the price of the product and for which no tax revenue is collected.  And to add to the story of unintended consequences, in general today’s marijuana often exceeds 20 percent THC content compared to 3-5 percent in the pot of the 1990’s.  Given that the legalization has resulted in former light users becoming daily users, the health consequences can only be bad.  It may take years, but one day there will be a reckoning like we have seen with tobacco.  Joining us to discuss all things marijuana and its new place in American society is Keith Humphreys a professor at Stanford University who specializes in drug policy.