"Starting in late 1999, DEA acted administratively to demand that the U.S. Customs Service enforce a zero-tolerance standard for the THC content of all forms of imported hemp—and hemp foods in particular. Development of DEA’s rules to support its actions sparked a fierce battle over the permissibility of imported hemp-based food products that lasted from 1999 until 2004.
"DEA followed up, in October 2001, with publication of an interpretive rule in the Federal Register explaining the basis of its zero-tolerance standard.78 It held that when Congress wrote the statutory definition of marijuana in 1937, it “exempted certain portions of the Cannabis plant from the definition of marijuana based on the assumption (now refuted) that such portions of the plant contain none of the psychoactive component now known as THC.”
"In March 2003, DEA issued two final rules addressing the legal status of hemp products derived from the cannabis plant. It found that hemp products “often contain the hallucinogenic substance tetrahydrocannabinols (THC) ... the primary psychoactive chemical found in the cannabis (marijuana) plant.”79 Although DEA acknowledged that “in some cases, a Schedule I controlled substance may have a legitimate industrial use,” such use would be allowed only under highly controlled circumstances. These rules set forth what products may contain “hemp” and also prohibit “cannabis products containing THC that are intended or used for human consumption (foods and beverages).”
"Both the proposed rule (which was published concurrently with the interpretive rule) and the final 2003 rule gave retailers of hemp foods a date after which DEA could seize all such products remaining on shelves. On both rules, hemp trade associations requested and received courtordered stays blocking enforcement of that provision. DEA’s interpretation made hemp with any THC content subject to enforcement as a controlled substance.
"Hemp industry trade groups, retailers, and a major Canadian exporter filed suit against DEA, arguing that congressional intent was to exempt plant parts containing naturally occurring THC at non-psychoactive levels, the same way it exempts poppy seeds containing trace amounts of naturally occurring opiates.80 Industry groups maintain that (1) naturally occurring THC in the leaves and flowers of cannabis varieties grown for fiber and food is already at below-psychoactive levels (compared with drug varieties); (2) the parts used for food purposes (seeds and oil) contain even less; and (3) after processing, the THC content is at or close to zero. U.S. and Canadian hemp seed and food manufacturers have in place a voluntary program for certifying low, industry-determined standards in hemp-containing foods. Background information on the TestPledge Program is available at http://www.TestPledge.com. The intent of the program is to assure that consumption of hemp foods will not interfere with workplace drug testing programs or produce undesirable mental or physical health effects.
"On February 6, 2004, the U.S. Court of Appeals for the Ninth Circuit permanently enjoined the enforcement of the final rule.81 The court stated that “DEA’s definition of ‘THC’ contravenes the unambiguously expressed intent of Congress in the CSA and cannot be upheld.”82 In late September 2004 the Bush Administration let the final deadline pass without filing an appeal.83
"In January 2017, HIA petitioned the U.S. Court of Appeals for the Ninth Circuit to block DEA’s implementation of its December final rule on marijuana extracts, which would designate certain hemp-derived nonpsychotropic products, such as CBD, as a “marihuana extract” subject to the CSA.84 Then, in February, 2017, HIA again petitioned the court alleging that DEA violated the court’s 2004 order when it indicated that a North Dakota hemp company would need a DEA registration and would be subject to other requirements before it could ship processed hemp products outside the state, even though these products were in accordance with state law and the 2014 farm bill.85
"In May 2018, DEA issued an internal directive to further clarify the ruling in the 2004 court case.86 The directive acknowledges that products and materials made from the cannabis plant that fall outside the CSA’s definition of marihuana—such as sterilized seeds incapable of germination, oil or cake made from the seeds, mature stalks, and fiber from mature stalks—are exempt from CSA and may be “sold and otherwise distributed throughout the United States without restriction under the CSA or its implementing regulations.”87 Exempt cannabis plant material also includes “any other compound, manufacture, salt, derivative, mixture, or preparation” of the above items, despite the presence of cannabinoids. The directive further acknowledges that such exempt products and materials may be imported into the United States without restriction (under the Controlled Substances Import and Export Act, 21 U.S.C. §§951-971) or exported from the United States (“provided further that it is lawful to import such products under the laws of the country of destination”). The directive does not address marijuana extracts and resins.
"Some in the hemp industry are interpreting the 2018 directive as providing an indication of DEA’s position regarding extracts such as CBD from exempt plant materials, including industrial hemp. They claim that this could provide an indication that CBD extracted from hemp could be considered exempt from CSA regulation and DEA’s jurisdiction.88 They also acknowledge that some research indicates that meaningful levels of CBD might not be readily extracted from exempt plant materials such as industrial hemp."
Johnson, Renée. Hemp As An Agricultural Commodity. Congressional Research Service. Washington, DC: Library of Congress, June 28, 2018.