An Alcohol, Tobacco and Firearms senior agent assigned to the Phoenix office in 2010, Dodson's job is to stop gun trafficking across the border. Instead, he says he was ordered to sit by and watch it happen. Dodson's bosses say that never happened. Now, he's risking his job to go public. Agent Dodson and other sources say the gun walking strategy was approved all the way up to the Justice Department. The idea was to see where the guns ended up, build a big case and take down a cartel. And it was all kept secret from Mexico. ATF named...