Forces led by the breakaway faction of Riek Machar deliberately killed an estimated 2,000 civilians in Dinka villages of Jonglei State and wounded several thousand more over the course of two months.
Other commanders with whom he initially spoke suggested that he bring in Riek Machar, a well-liked senior commander whose base in Nasir gave him easy access across the Ethiopian border to Gambela and the SPLA rear bases where Lam and Riek could gain political support.
Hall's exclusive reports include a profile on Emma McCune, an English woman who married Southern Sudanese guerrilla commander Riek Machar; the draining of Iraq's marshes by Saddam Hussein, and a one-on-one with former Kurdish PKK leader Abdullah Öcalan in a Syrian safehouse.