I would like some citations on #2. Hangovers, liver failure, and lung cancer do serious economic damage. I don't know of any evidence that pot decreases productivity though there has been plenty of DARE shit that says so. My unscientific study of every human I've ever met as an adult shows that 60% of people smoke sometimes with no ill effects and 10-15% of people I've meet are seriously blunted all day and turn out good work. Some of the people I know that are the best at their jobs consume amounts of cannabis that the average non user would find offensive.