US Deputy Attorney General’s Guidance
“Persons who are in the business of cultivating, selling or distributing marijuana, and those who knowingly facilitate such activities, are in violation of the Controlled Substances Act, regardless of state law. Consistent with resource constraints and the discretion you may exercise in your district, such persons are subject to federal enforcement action, including potential prosecution. State laws or local ordinances are not a defense to civil or criminal enforcement of federal law with respect to such conduct, including enforcement of the CSA.
Those who engage in transactions involving the proceeds of such activity may also be in violation of federal money laundering statutes and other federal financial laws.”
Read the letter in full: Cole Memo June 2011