New PBS documentary exposes the tasing and beating death of a Mexican immigrant by U.S. border agents in California, and has renewed scrutiny of what critics call a culture of impunity. In May 2010, 32-year-old Anastasio Hernández Rojas was caught trying to enter the United States from Mexico near San Diego. He had previously lived in the United States for 25 years and was the father of five U.S.-born children. But instead of deportation, Hernández Rojas’ detention ended in his death. A number of border officers were seen beating him, before one tasered him at least five times. He died shortly afterward. The agents say they confronted Hernández Rojas because he became hostile and resisted arrest. But previously undisclosed videos recorded by eyewitnesses on their cell phones show a different story. “All eyewitnesses that we spoke to basically tell the same story of a man hogtied and handcuffed behind his back, not resisting, being beaten repeatedly — by batons, by kicks, by punches, by the use of a taser — for almost 30 minutes until he died,” says reporter John Carlos Frey, whose exposé aired in a national television special last Friday night, as part of a joint investigation by the PBS broadcast, “Need to Know,” and the Investigative Fund of the Nation Institute.