At a Senate Judiciary Committee hearing on "Conflicts between State and Federal Marijuana Laws," Senator Chuck Grassley (R-Iowa) claimed that marijuana prohibition was based on "what science tells us about this dangerous and addictive drug." He followed that by noting that there's "a process that exists for moving drugs on and off" the list of prohibited substances, but that "the scientific standard to do that hasn't yet been met for marijuana."
Grassley presumably means that the standard to remove marijuana from the list of prohibited substances has not yet been met, but instead of providing evidence to support that claim, he instead appealed to the standing of the United States in the international community. "The United States and 180 other nations signed a treaty that requires the United States to limit the distribution and use of certain drugs, including marijuana, to exclusively scientific and medical use."
"It's something this country gave its word to do," Grassley continued. The legalization of marijuana for recreational use in Washington and Colorado sends "the wrong message to violators of federal law." Moreover, it has led to the exportation of marijuana from states where its cultivation is legal to those in which even the possession of it is not.
"Why has the Justice Department decided to trust Colorado?" he asked. "It has become a significant exporter of marijuana."
He later claimed that "some experts claim [these laws] will create a Big Marijuana industry, including a Starbucks of marijuana." Grassley's comment echoes the language of Ken Sabet of Smart Approaches to Marijuana, a drug addiction prevention group, who was widely quoted as saying about the Colorado and Washington laws that "[w]e're about to create Big Marijuana by allowing the commercial production, retail sales and mass advertising of this drug similarly to how we have had Big Tobacco for the last hundred years."
Watch a video of Sen. Grassley's testimony below.