The private security company Blackwater admitted on Tuesday for the first time that one of its employees shot and killed an Iraqi guard inside the Green Zone in December. The disclosure came during a landmark hearing on the role of private contractors in Iraq. Among those to testify was Katy Helvenston. Her son Scott was one of the four Blackwater employees killed in Fallujah in 2004. Katy Helvenston joins us to talk about why she wants Blackwater held accountable for her son’s death. We’re also joined by Jeremy Scahill, author of the forthcoming book “Blackwater: The Rise of the World’s Most Powerful Mercenary Army.” [includes rush transcript]