FILE - This Jan. 3, 2013 file photo shows state and department shields hanging in the entryway to the Colorado Department of Revenue, Medical Marijuana Enforcement Division in Denver.

 

              FILE - This Jan. 3, 2013 file photo shows state and department shields hanging in the entryway to the Colorado Department of Revenue, Medical Marijuana Enforcement Division in Denver.
FILE - This Jan. 3, 2013 file photo shows state and department shields hanging in the entryway to the Colorado Department of Revenue, Medical Marijuana Enforcement Division in Denver. It took 50 years for American attitudes about marijuana to zigzag from the paranoia of "Reefer Madness" to the excesses of Woodstock back to the hard line of Just Say No. And now, in just a few short years, public opinion has shifted so dramatically toward pragmatic acceptance of marijuana that even those who champion legalization are surprised at how quickly attitudes are changing and states are moving to approve the drug for medical use and just for fun.(AP Photo/Brennan Linsley, File)