"US Federal Government's obstruction of research" is not a matter governed by MEDRS. Other sources will do. And yes, the government, through Federal anti-marijuana laws, has prevented research and made it very difficult. It has only allowed some research which was designed to present marijuana in a negative light and has covered up research which was favorable. It has even patented some pharmaceutical cannabis-based products designed for beneficial medical use, and then failed to use those patents, effectively blocking such patented use. This is part of US history and part of the history of the failed War on Drugs. That war is far more political than it is medical or scientific. It has misused science all along. As Sanjay Gupta put it: "We have been terribly and systematically misled for nearly 70 years in the United States, and I apologize for my own role in that."