The trial of commanding officer Lt. Jorge Vinicio Sosa Orantes began last week, ProPublic reports. It is the first trial in the United States involving an atrocity from Guatemala’s 30-year civil war. It is also the first full airing of the Dos Erres case in a U.S. court. Sosa played a lead role in one of the worst war crimes in the recent history of the hemisphere: the massacre of 250 people in the Guatemalan hamlet of Dos Erres in 1982. He is charged with fraudulently obtaining U.S. citizenship years later by concealing his participation in the massacre.