Voters legalized marijuana for recreational use in Washington and Colorado in 2012, and it's legal in a half dozen other states, too, but it remained illegal under federal law.
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As states worked on regulation for the industry the following year, Deputy Attorney General James Cole issued a memo to all U.S. attorneys that was published through the U.S. Department of Justice on Aug. 29, 2013. It later became known as the Cole memo.
It cleared up some of the uncertainty about how the federal government would respond as states began allowing sales for recreational and medical purposes.
The directive said the Department of Justice would not stand in the way of states that legalize marijuana and outlined the enforcement priorities that were particularly important to the federal government:
- Preventing the distribution of marijuana to minors;
- Preventing revenue from the sale of marijuana from going to criminal enterprises, gangs and cartels;
- Preventing the diversion of marijuana from states where it is legal under state law in some form to other states;
- Preventing state-authorized marijuana activity from being used as a cover or pretext for the trafficking of other illegal drugs or other illegal activity;
- Preventing violence and the use of firearms in the cultivation and distribution of marijuana;
- Preventing drugged driving and the exacerbation of other adverse public health consequences associated with marijuana use;
- Preventing the growing of marijuana on public lands and the attendant public safety and environmental dangers posed by marijuana production on public lands; and
- Preventing marijuana possession or use on federal property.
The marijuana business has since become a sophisticated, multimillion-dollar industry that helps fund some government programs. Eight states and the District of Columbia have legalized marijuana for recreational use, and California's sales alone are projected to bring in $1 billion annually in tax revenue within several years.
But the Sessions Justice Department believed the Cole memo created a "safe harbor" for marijuana sales that are federally illegal, Justice Department officials said. Sessions in the memo called the Obama guidance "unnecessary."
Sessions' policy will let U.S. attorneys across the country decide what kinds of federal resources to devote to marijuana enforcement based on what they see as priorities in their districts. Officials couldn't say what the ultimate impact will be on the legal industry or whether it will lead to more pot prosecutions.
Nor is it clear how the memo might affect states where marijuana is legal for medical purposes. A congressional amendment blocks the Justice Department from interfering with medical marijuana programs in states where it is allowed. Justice officials said they would follow the law, but would not preclude the possibility of medical-marijuana related prosecutions.
The Associated Press contributed to this story.