Workplace drug testing for marijuana may need updating in light of changing laws, a case before the Colorado Supreme Court suggests. Kai-Huei Yau/MCT/Landov hide caption

itoggle caption Kai-Huei Yau/MCT/Landov

A man smokes marijuana outside Uruguay's parliament in Montevideo on Wednesday, where lawmakers in the lower house debated and passed a bill that would legalize marijuana and regulate its production and distribution. Matilde Campodonico/AP hide caption

itoggle caption Matilde Campodonico/AP

The United States Supreme Court: a temple to complexity and self-reinforcing feedback loops? Chip Somodevilla/Getty Images hide caption

itoggle caption Chip Somodevilla/Getty Images

The number of new drug shortages each year in the U.S., from 2001 through Dec. 21, 2012. University of Utah hide caption

itoggle caption University of Utah