The Huffington Post 
Nov 15, 2012
“We have sponsored legislation at the federal level to remove criminal penalties for the use of marijuana because of our belief in individual freedom,” Frank and Paul wrote in a letter  to Obama. “We recognize that this has not yet become national policy, but we believe there are many strong reasons for your administration to allow the states of Colorado and Washington to set the policies they believe appropriate in this regard, without the federal government overriding the choices made by the voters of these states.”
Frank and Paul presented the new marijuana laws as a sort of challenge to “those who disagree with us,” noting opponents “should welcome the opportunity to put their theories to a test.”
Both Frank and Paul are ardent supporters of marijuana legalization. In 2011, the two pushed  legislation to end the federal ban on marijuana and let the states decide on legalization.