As Allan A. Ryan, Jr. starts teaching his summer school course “War Crimes, Genocide and Justice,” his ideas on those topics are being implemented half-way across the globe—in Rwanda, where the country is banking on his policy suggestions to deal with the legacy of its 1994 mass genocide.

Ryan has been the director of intellectual property for Harvard Business School Publishing for the last year, after serving for 15 years as University Attorney in Harvard’s Office of the General Counsel.

In 1995, while Ryan was also teaching a course on human rights at Boston College Law School, Rwanda invited him as one of a small group of genocide experts to help with the formidable problem of redressing the wrongs committed during the 100-day long massacre, which claimed 800,000 lives.

When he traveled to Rwanda, Ryan was deeply shaken to learn that there was “still evidence of [genocide] everywhere.”

He vividly recalled a town enveloped by a stench “you could almost taste” from the odor of bodies still being buried in a mass grave.

“On one side, there were the torsos, and on the other were the skulls,” Ryan said. “It was too difficult to match them up, so the survivors had to just bury them all together.”

No Rwandan family went unaffected in the genocide that pitted the majority Hutu population against the Tutsis, with nearly 115,000 Rwandans suspected of having taken part in the machete-wielding frenzy.

The large scope of the Rwandan genocide made the possibility of criminal prosecution for war crimes beyond possibility.

“My first thought was, ‘This country is too small, too poor to try all these people,’” Ryan said. “It would be a staggering job in [the United States], and it’s out of the question in Rwanda.”

His pessimism proved well-founded. Since trials began in 1996, they have moved at the pace of about 1,000 per year—at which rate most of the suspects will die in prison before ever facing prosecution.

Ryan realized that “an alternative to trials—not an alternative to justice” was what was needed.

“You don’t need a trial to get justice,” he said.

And earlier this month, in accordance with much of the advice outlined in a memo written by Ryan in 1995, Rwanda did away with the orthodox trial system. In its place, it has reinstituted the gacaca ( pronounced ga-CHA-cha), an ancient tribal custom—literally “justice on the grass” in Kinyarwandan, Rwanda’s most spoken language.

When Ryan first heard of gacaca from a Rwandan member of his committee, he quickly grasped that though it had “nothing to do with the law,” it had “everything to do with justice.”

For Ryan, the gacaca system represents a completely different approach to justice than the Western method, but one that better fits the situation.