What exactly happened that day in Fallujah?
Relatives of four slain Blackwater USA contractors, from left, Kristal Batalona, Kathryn Helvenston-Wettengel, Rhonda Teague and Donna Zovko, testify at a House hearing in Washington, D.C., in February. The families are suing Blackwater in the hope that their questions on what happened to their loved ones in Fallujah will be answered.