Ball wrote software that allowed the commission to aggregate and analyze the human rights records of officers in the El Salvadoran Army. The results forced a quarter of the military leadership to retire.
"We figured ... they were going to blow our office up," Ball says. Instead, the officers sued the commission – an unexpected recourse to the rule of law in a postconflict country. "We were tickled pink," Ball recalls.
Ball went back to Michigan, but word of his work got out and he spent the next years bouncing between truth and reconciliation projects – South Africa, Haiti, Guatemala, East Timor, and Peru – finding ways to uncover the scale and pattern of human rights violations.
The level of expertise and discipline his work requires puts Ball on par with Olympic runners or violin virtuosos. Lara J. Nettelfield, a Balkans scholar at Simon Fraser University in Vancouver, British Columbia, says he's "one of the very small group of people in the world who could properly analyze and consult on [mass atrocities]."