In an historic move to respect Native American sovereignty earlier this month, the US Department of Justice (DoJ) issued a memo instructing US attorneys to not interfere with tribes cultivating or selling cannabis on reservation lands. The caveat is that the tribes have to be in conformity with state law, limiting the new policy to states that have legalized (Colorado, Washington) or have strong medical marijuana programs (California, Montana). Tribes must also maintain "robust and effective regulatory systems," as John Walsh, US attorney for Colorado, told the Los Angeles Times. But US attorney for North Dakota Timothy Purdon, the Attorney General's pointman on Native American Issues, added: "The tribes have the sovereign right to set the code on their reservations." US News & World Report even speculated: "Marijuana may displace casinos as reservation cash cows."