Seattle law enforcement's mellow attitude toward pot was on display at this year's annual Hempfest, where the cops were at the gate — handing out bags of Doritos. Martin Kaste/NPR hide caption

itoggle caption Martin Kaste/NPR

Maj. Nidal Hasan faces 13 charges of murder and 32 of attempted murder for the November 2009 shootings at Fort Hood, Texas. Reuters/Landov hide caption

itoggle caption Reuters/Landov

Jeff Brantingham, creator of PredPol, demonstrates computer-generated "predictive policing" zones at the Los Angeles Police Department Unified Command Post in Los Angeles last year. Damian Dovarganes/AP hide caption

itoggle caption Damian Dovarganes/AP

Take a tour of the Hanford site, a nuclear production complex in Richland, Wash., and you'll see the hundreds of mechanical water pressure gauges wired to the process tubes inside the core. Tour guide Paul Vinther warns that bumping these gauges could throw off the readings enough to trigger a an emergency shutdown of the reactor. Martin Kaste/NPR hide caption

itoggle caption Martin Kaste/NPR