The story seemed like lifestyle press catnip: from a sleepy corner of southeastern Belgium comes the first modern abbey beer brewed by nuns. Some of the best-known Belgian beers originated from clerics, but for centuries their craft was the exclusive domain of monks who eventually started licensing their recipes to lay professionals. Here comes girl power, at Maredret Abbey, whose first two brews debuted a couple of years ago.

In coverage by Reuters and the BBC, and on the YouTube channel of Maredret’s licensee brewer, John Martin, the most visible face of the product is a beatific-looking, soft-spoken Black nun with an East African accent. She explains the workings of Maredret Abbey and the nutritional properties of spelt, one of the grains in their recipe. She is part of a group of just 20 or so nuns who maintain the somber, neo-Gothic complex with a poky little gift shop that sells postcard-size illuminated manuscripts, hand-crocheted doll clothes, jam, herbal tinctures, and beer.

There’s just one problem, and it’s pretty thorny. The nun in question is Sister Gertrude, née Consolata Mukangango. Feel free to google her. In doing so you might be performing more due diligence than Martin, whose representative declined Air Mails requests for comment. Rather than “hops” or “spelt,” you will see words such as “complicit,” “Rwandan genocide,” and “served seven years in prison.”

In 2001, Mukangango and Sister Maria Kisito, née Julienne Mukabutera, a novice under Sister Gertrude’s charge at Sovu Monastery in southern Rwanda, were convicted by a Belgian court of participating in a series of abetment and obstruction-related crimes against humanity that took place during April and May of 1994. (Belgium ruled Rwanda for almost 50 years as a colonial power before independence, in 1962; ties between the countries remain strong.)

Sisters Gertrude and Maria, both Hutu, did not personally raise machetes at Sovu Monastery. But the two were found to have conspired with local politicians who helped organize the genocide of Rwanda’s Tutsi minority, which took the lives of between 500,000 and 1 million people countrywide.

Sister Gertrude (née Consolata Mukangango) and fellow nun Sister Maria (Julienne Mukabutera) on trial in Brussels in 2001.

With the nuns’ support and complicity, approximately 7,000 refugees died over the course of three different massacres. Many hundreds were burned to death with gasoline provided by Sister Maria. A handful of the dead were the families of serving Tutsi nuns pushed out of the convent by Sister Gertrude. She testified in Brussels that she did so in fear for her own life.

There is reason to believe that Sister Gertrude, the convent’s first African Mother Superior, was frightened. She was half Tutsi herself, and those thought to be protecting Tutsi often faced the same violence. But the direct testimony of survivors, most readily available in “Obstruction of Justice: The Nuns of Sovu in Belgium,” a 2000 report by the British NGO African Rights, is hair-raising. They speak of Sister Gertrude laughing and coldly shooing refugees away.

Rather than “hops” or “spelt,” you will see words such as “complicit,” “Rwandan genocide,” and “served seven years in prison.”

The report also reprints a letter (used as evidence at her trial) that Sister Gertrude wrote on May 5, 1994, inviting the mayor, indisputably one of the genocide’s local leaders, “to come settle this problem … so that the monastery can take up its daily activities without any anxiety.”

Very few fleeing the convent escaped the militia on May 6, 1994. Sister Gertrude then went back to supervising gardening and prayers until the nuns were evacuated. She and Maria arrived at Maredret, the Benedictine abbey that founded their community in Sovu, in August 1994.

Another handful of those who Sister Gertrude had helped lead to slaughter were Rwandan team members of a U.S.-government-funded aid organization. It was led by John Berry and Carol Pott Berry, who went on to edit the book Genocide in Rwanda: A Collective Memory. The group was using Sovu’s facilities for a workshop when the violence broke out, and Berry and Pott were evacuated with other Americans. Berry testified at Sister Gertrude’s trial. “I’ve spent 30 years trying to come to grips with this,” he tells Air Mail by phone from his home, in Seattle.

Sovu wasn’t the only church property in Rwanda used as a killing field during three hellish months of Tutsi and moderate Hutu being hacked to death by machetes en masse. During past periods of heightened violence against Tutsi—notably in 1959 and 1973—churches in Rwanda were sanctuaries. In 1994, to the shock of many, they were targets, sometimes with the blessing of the local clergy.

The Vatican did as little as the United Nations and the Belgian military to intervene in the breakdown of order while it was ongoing, and survivors complained that the Catholic Church sheltered the Sovu nuns afterward—an all too familiar tale.

The trial was the first and one of the only instances of charges brought under universal jurisdiction, thanks to a Belgian law passed in 1993, and so it was an ongoing headline story. As was the case during the Nuremberg trials after World War II, now Belgium could pursue any international actor, regardless of their citizenship or the location of their alleged crimes.

By all accounts, the country’s hands were messy in Rwanda during their decades of colonial control. The Belgians were the ones who created ethnic hierarchies in the first place, installing the “more European-seeming” Tutsi minority at the top, and then abruptly shifting to favor the Hutu in the mid-20th century, laying the groundwork for the violence that eventually engulfed the country. Critics of the trial felt Belgium was overplaying its hand to expunge its own guilt.

By her own account, captured in the 2018 testimonial book Rwanda 1994: The Words of Sister Gertrude, authored by Jerôme Gastaldi, the former Mother Superior held her tongue for much of the trial. But she lets it rip in the book, accusing witnesses of lying to settle petty scores over theology and abbey-level politics. She is herself a victim, she pleads. She deplores not having always made good decisions, but she begs us to consider the chaos. “Do you think you made any mistakes?” asks Gastaldi. “I don’t know, maybe,” Sister Gertrude replies.

Under Rwanda’s current president, Paul Kagame, leaders of the killings have been prosecuted in Rwandan criminal courts; in the International Criminal Tribunal for Rwanda, in Arusha, Tanzania; and in community tribunals called gacaca courts. There, if the guilty show remorse and provide a full and honest accounting of their crimes, they are given more lenient sentences.

While controversial, gacaca courts were in the national interest, both to process hundreds of thousands more participants than the criminal courts could handle and to find a way forward so that Hutu and Tutsi could live side by side again in one of the world’s most densely populated countries.

Ernest Sagaga, the president of the Belgian chapter of Ibuka, a Rwandan survivors’ association, explains that accountability and remorse have been crucial ingredients in reconciliation. “Forgiveness is an individual process,” he says. “We don’t pronounce what should be done.” But Sagaga reported on gacaca courts for years as a journalist for BBC World Service. While he was suspicious at first, he saw their efficacy. “They allowed justice by way of peers. People were able to rebuild not only their lives but their friendships.”

Taking personal moral responsibility does not appear to be happening for Sister Gertrude. One could say that after seven years in a Belgian prison, she had paid her debt to society—even if not in a Rwandan jail—and now she should be free to retail malted beverages. Except she still hasn’t really admitted her guilt.

Sagaga read Gastaldi’s book with Sister Gertrude, and he’s not impressed. “She still says she has a clear conscience!” he tells me. “I’m not a doctor, but I don’t know how one could say that.”

Berry is similarly flabbergasted. “I had about 12 people with me [at Sovu], and five of them were killed,” he recalls. “She drew up a list, and then told the militia to go to work to ‘clean out’ the garbage,” he continues, noting that the camaraderie between the powers that be and Sister Gertrude was such that she served them refreshments after a hard day’s work. “So they came and did their work, and then they came to the convent at the end of the day to get their beer.”

No, really. Beer. It’s a tragic irony that the fruity bitterness of Maredret Extra, with its sweet pear and ginger notes, and the stronger bite of Maredret Triplus 8 percent cannot quench.

Alexandra Marshall is a Writer at Large at AIR MAIL and a contributor to W, The Wall Street Journal, Vogue, and Travel + Leisure. She chronicles her recent relocation to Le Perche in the newsletter An American Who Fled Paris