The overwhelming majority of people think there should be age restrictions on the recreational use of marijuana. Ben Nelms/Reuters/Corbis hide caption
marijuana
Tuesday
Sunday
People smoke marijuana, presumably, because it affects their brains, not despite that fact. Above, people in Sao Paulo, Brazil, campaign for the legalization of marijuana. Nelson Almeida/AFP/Getty Images hide caption
Thursday
Former Supreme Court Associate Justice John Paul Stevens likens making pot illegal to Prohibition. In his new book, Six Amendments, he proposes constitutional changes including a curb on an individual's right to bear arms. Chip Somodevilla/Getty Images hide caption
Sunday
With the Colorado state capitol in the background, Cannabis Cup attendees dance and smoke pot at the annual 4/20 marijuana festival in Denver. Brennan Linsley/AP hide caption
Sunday
A customer eyes marijuana samples at a Denver dispensary. The makers of a newly unveiled vending machine are hoping to change how pot is sold in stores. Theo Stroomer/Getty Images hide caption
Monday
Monday
Monday
Marijuana is stored in bins for trimming and packaging in preparation to be sold retail at 3D Cannabis Center, in Denver. Brennan Linsley/AP hide caption
Tuesday
Monday
C. Nash smokes after possession of marijuana became legal in Washington state on Dec. 6, 2012. Ted S. Warren/AP hide caption
The teenage years are the last golden opportunity to build a healthy brain, researchers say. So smoking pot might not be so smart. Tomas Rodriguez/Corbis hide caption
Friday
A bag of marijuana being prepared for sale sits next to a money jar at BotanaCare in Northglenn, Colorado, in this file photo taken on December 31, 2013. Rick Wilking/Reuters/Landov hide caption
Monday
Research in mice offers new clues as to why Harold and Kumar were so motivated to get to White Castle. Todd Plitt/Getty Images hide caption
Sunday
Truffles are among the many foods infused with THC – the chemical in marijuana that gives you a high — already for sale in Colorado. Luke Runyon/KUNC/Harvest Public Media hide caption
Marijuana-Laced Treats Leave Colorado Jonesing For Food-Safety Rules
Friday
A marijuana bud and cash at a shop in Denver. An owner of marijuana stores in the city says of his company's bank account, "We treat it like gold." Ed Andrieski/AP hide caption