Every April for 20 years now, Rwandan-born Dafroza Gauthier, 59, an industrial chemist, is reminded of the genocide. Among its victims were her 69-year-old mother and relatives from the extended family.

"I can't tell you the numbers killed, there were so many," she tells DW, seated in the cozy terraced house she shares with her husband Alain, 65, a retired French teacher, in Reims, France. The couple has been married for nearly 40 years. They've raised children and grandchildren and consider themselves ordinary French citizens. But the genocide changed them. The genocide changed everything.

"It's impossible to live a normal life after a genocide," says Dafroza, who is Tutsi. She is tall, with elongated features, and possesses the regal bearing of a gazelle in a casual pullover and stretch jeans that accentuate her gamin looks.

For the past 13 years Dafroza and Alain have tracked fugitives who fled the Rwandan genocide and settled in France. Some of the people they've found have led respectable lives as doctors or priests in their communities.

The Gauthiers set up the Collective of Civil Plaintiffs for Rwanda (CCPR) in 2001 to file civil cases against alleged perpetrators of the genocide. The real work lays in identifying them in the first place and then deposing scores of witnesses to give testimony.

In the French press, the Gauthiers have often been compared to Nazi hunters Serge and Beate Klarsfeld, who gathered evidence used to prosecute many of the biggest war criminals implicated in the Holocaust.

Historical precedent

Last month the Gauthiers were rewarded for their efforts when a six-week trial ended with the conviction of a former Rwandan intelligence chief on French soil, setting a historical precedent. A jury found Pascal Simbikangwa guilty of complicity in an act of genocide that claimed hundreds of thousands of lives over the course of three months.

The victims were mainly the Tutsi minority, but included moderate Hutus who were branded traitors by the extremists in power. The wheelchair-bound Simbikanagwa, who has been paraplegic since an auto accident in the 1980s, was sentenced to 25 years in prison.

"What was important for us was the acknowledgement of culpability by a popular jury for the crime of genocide. There is no proper sentence that corresponds to such a crime. Twenty-five years? What is that for someone who has killed hundreds of thousands of people?" asks Alain Gauthier.

Dafroza was pleased with the verdict in the Simbikangwa case, but appalled by the man's conduct in the courtroom.

"I feel deeply pained, because he never once said he was sorry for what he had done. He denied everything. He said he never saw a single cadaver in Kigali. Can you imagine that? That's impossible," she says. "Or maybe it's his contempt for the victims. He doesn't regard them as human. They're cockroaches to him, so it's all right to kill them."

The Gauthiers have filed another 24 complaints with the Paris courts, they say.

If it weren't for them, none of the Rwandan fugitives from justice would have ever been prosecuted, says Orphelie Latil of Survie, a Paris-based NGO that lobbies for democracy and human rights in Africa.

Latil also believes the official UN estimate that 800,000 perished in the genocide is understated. "It's closer to a million," she says. That would have been more than 10 percent of the tiny Central African's population at the time.

ID cards meant death

Dafroza saw her mother for the last time in Kigali a month before the date the systematic killing is said to have officially begun. Preparations for the genocide were already in place. Roadblocks had been set up all over the capital, so that, even then, no Rwandan Tutsi could cross a barricade manned by Hutu militias and come out alive on the other side.

"The personal identity card designating ethnicity, a legacy of the Belgian colonialists who had introduced them in 1931, had became an instrument of death at the checkpoint," explains Alain Gauthier.

Since Dafroza's family couldn't leave Kigali, they went into hiding once the rampage started. Her mother was struck down by two bullets on April 8. Dafroza was lucky to have been at home in France.

Yet for her, the pursuit of war criminals is not about vengeance but justice. Only once justice has been done is reconciliation possible, she says.

"Justice is about permitting the accused to recognize what they did was wrong and ask forgiveness from families of the victims. For me personally, if my family's killers were to apologize, I'd forgive them," she says. "But so far no one has come forward."