Breathalyzer for marijuana use? | West Coast Wrap

Tonight, the FBI reveals ties between a California man and the teenage girl behind this week's deadly school shooting in Wisconsin. See why authorities believe he had plans to carry out an attack of his own and the action taken against him. And, a breathalyzer for marijuana use? Researchers in the West are trying to make that a reality. Tonight, law enforcement officials explain why they think the device may not be needed.