The U.S. Justice Department will draft a plan to more effectively discern whether state and local governments are effectively enforcing federal priorities for state-licensed cannabis sales, a governmental watchdog said Monday. In a 45-page report, the U.S. Government Accountability Office (GAO) found that the department has so far failed to document how it monitors state enforcement of a federal ban on marijuana following its issuance in August 2013 of guidance outlining the instances when state-sanctioned dispensaries could face federal indictments. In the 2013 memorandum, then-Deputy Attorney General James Cole instructed U.S. attorneys to focus their prosecutorial efforts on marijuana businesses...