Answer:

THE TENTH AMENDMENT

            “The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved for the States respectively, or to the people.” U.S. Const. amend. X. 

            Medical care and what constitutes valid medicine has been reserved to the states through the police power. Today, 38 states have legalized medical or adult use marijuana cannabis despite the federal prohibition of such usage under the federal Controlled Substances Law. Even so, neither Congress nor the U.S. Attorney General has ever found a “positive conflict” between these state laws and the fact that they negate and nullify the supremacy of the federal controlled substances act.