(March 2016) The States of Nebraska and Oklahoma brought a lawsuits against Colorado complaining that due to the passing of Amendment 64 their states (where marijuana is still in stale prohibition) are getting an unwanted supply (traffic) of marijuana that has been cultivated in Colorado.
Attorney’s for Nebraska and Oklahoma both claim Colorado is putting an undue burden on their states and requiring them to step-up controlled drug (read: marijuana) enforcement. They are saying, in short, that Colorado is acting unconstitutionally in allowing the recreational cultivation and distribution of marijuana.
The US Supreme court threw out the case.
Read more here: http://kdvr.com/2016/03/21/supreme-court-throws-out-states-challenge-to-colorado-marijuana-law/