Luis Moreno-Ocampo made his name two decades ago as a young assistant prosecutor in Argentina's trials of army commanders accused of masterminding the "dirty war" of the late 1970s. They were charged with human rights violations and also of malpractice in the Malvinas/Falklands war. The initial trial represented the first prosecution of top commanders for mass killings since Nuremberg.

By 1988, Mr Moreno-Ocampo (right) had become the main prosecutor in other military-related proceedings. But in 1992, he resigned as chief prosecutor for the federal criminal court of Buenos Aires and established a law firm there, specialising in criminal and human rights law and corruption control. For the next decade he combined his private practice with a mixture of "pro bono" activity, academic positions and work for non-governmental organisations. He represented victims in the extradition to Italy of Erich Priebke, a former Nazi officer. He was a World Bank consultant and visiting professor at Stanford and Harvard universities.