Abstract
The cannabis-policy landscape is undergoing dramatic change. Although many jurisdictions have removed criminal penalties for possessing small amounts of cannabis and more than half of U.S. states allow physicians to recommend it to patients, legalizing the supply and possession of cannabis for nonmedical purposes is a very different public policy. Since the November 2016 election, 20% of the U.S. population lives in states that have passed ballot initiatives to allow companies to sell cannabis for any reason and adults 21 or older to purchase it. Although other states may move toward legalization, uncertainty abounds because of the federal prohibition on cannabis. The Obama administration tolerated these state laws; it’s unclear what the Trump administration will do.