As a war reporter in the 1990s, I witnessed the world’s failure to prevent two genocides—and the struggle to hold perpetrators accountable afterward.
In Bosnia in 1995, more than 8,000 Muslim men and boys were slaughtered in Srebrenica, a town that the United Nations had declared a safe haven. In Rwanda in 1994, an estimated 800,000 people were killed over 100 days. Both atrocities happened under the gaze of the international community and revealed how ill-equipped it was to gather and preserve evidence of crimes against humanity.
Back then, investigations relied on survivors’ testimonies, journalists’ notes, and the slow and grisly work of exhuming mass graves. When the International Criminal Tribunal for the Former Yugoslavia began its probe into the Srebrenica incident in 1996, Serb forces had already dug up and reburied bodies to hide evidence. But something new emerged from Bosnia: satellite imagery.
U.S. intelligence used satellites and geospatial intelligence to detect disturbed soil around villages near Srebrenica, such as Pilica and Nova Kasaba—possible mass grave sites. The imagery was rudimentary and often classified, but it marked the beginning of a technological revolution in accountability, leading to international pressure as well as helping to guide on-the-ground research. The images were used as evidence in war crimes investigations, shared with the United Nations and the International Criminal Tribunal for the Former Yugoslavia, and later presented publicly.
By contrast, in Rwanda, there were no satellites, no drones, and limited forensic access. Much of this was because of how quickly the genocide unfolded and how little international monitoring there was on the ground. The U.N. had a limited mandate in Rwanda, and initially, there were few international reporters there. Most importantly, at the time, satellite imagery was expensive, and identifying graves in Rwanda from above was especially difficult due to the country’s dense forests and remote rural areas.
Investigators—U.N. human rights experts, journalists, and later the U.N. Commission of Experts—instead relied almost entirely on human testimony. The result was a slow, painful process; the thousands of testimonies collected were indispensable for truth-telling and for the Gacaca courts, a transitional justice system. The United Nations’ International Tribunal in Rwanda opened in 1994 and closed in 2015, indicting 93 individuals during that time—but it was neither swift nor comprehensive justice.
More than 30 years later, the tools of war crimes investigation have shifted beyond recognition because of sweeping changes in technology. What once depended on a handful of investigators now depends on terabytes of data, photographs, and radio interception. Open-source intelligence, or OSINT, has redefined how we track, verify, and prosecute atrocities.
The International Criminal Court began using satellite imagery systematically in its investigation in Darfur, Sudan, in the mid-2000s. During the civil war in Syria, the American Association for the Advancement of Science published open analyses of destroyed villages and mass graves. In Syria, nongovernmental organizations also used commercial satellite images to identify bombed hospitals, massacres, and detention sites. Citizen journalists in cities such as Aleppo captured evidence of barrel bombs and double-tap bombing—two strikes carried out in quick succession, so the second hits first responders helping victims of the first strike—by Russian planes.
A new generation of digital investigators soon followed. Bellingcat, an investigative journalism group, used open-source tools first to identify perpetrators of attacks in Syria and later to identify Russian forces in Ukraine. Forensic Architecture, founded in London by a British-Israeli architect, reconstructed bombings using architectural modeling and geolocation data in cases such as an airstrike on a theater in Mariupol, Ukraine, in March 2022.
Many major newspapers, including the New York Timeshave launched their own investigative teams that rely on OSINT specialists. OSINT has blurred the line between journalism and criminal investigation—and it’s made impunity harder to sustain. Investigations now create public records of crimes that cannot be erased or denied. Everyone has a phone, and phones have cameras; organizations such as Eyewitness now work with citizens in war zones to capture images and document atrocities in real time, forcing moral and political consequences.
When I began reporting on wars in the late 1980s in Gaza and the West Bank, my tools were a notebook and, later, a satellite phone the size of a coffee table. There was no internet, no social media, and no instant imagery. Today, my organization—the Reckoning Project—operates differently. We combine OSINT, satellite analysis, and digital verification with traditional witness interviews and human intelligence. We train journalists and lawyers to work together so that evidence gathered in the field can be admissible in court. We work directly with prosecutors, helping them build their files.
The Reckoning Project convened a symposium at Yale University in early November called “How to Catch a War Criminal in the 21st Century.” Our focus was on three current conflicts—the Israel-Hamas war in Gaza, the Russia-Ukraine war, and the civil war in Sudan—and how technology has transformed the pursuit of justice. We brought lawyers, analysts, data scientists, and journalists together to see how we can fight criminality and catch perpetrators sooner.
In Sudan, where more than 150,000 people are estimated to have died in fighting between the Sudanese Armed Forces and the paramilitary Rapid Support Forces (RSF) since April 2023, the evidence is literally visible from space. In October, the city of El Fasher fell to RSF forces after a cruel 18-month siege, with gaps in food supplies, electricity, and water access reaching critical levels. Following the takeover, there were reports of mass executions, rape, and deliberate obstruction of aid, as well as sitings of mass graves.
The fall of El Fasher marks a crucial moment. It is tragically too late to prevent what the U.S. State Department has already called a genocide—despite the desperate efforts of committed U.N. officials such as Tom Fletcher of the Office for the Coordination of Humanitarian Affairs, who visited Sudan last week. (Fletcher described El Fasher as a “crime scene.”) But now is the time to move on to documentation and potential prosecution. Stopping the ongoing violence is urgent—but so is gathering evidence.
“From the skies above El Fasher, satellites capture the stains of deliberately erased communities,” said Quscondy Abdulshafi, a Sudanese advisor to Freedom House, while speaking at the Yale conference. “Yet the world remains deaf to cries that rise louder than the guns. The moans of raped children and women echo through the rubble, demanding not sympathy—but justice.”
The Yale Humanitarian Research Lab has released satellite imagery showing “disturbances consistent with mass graves” outside El Fasher. The images appear to show systematic body disposal—in other words, a cleanup operation following massacres. Such images can help shift the international community’s perception that Sudan is an internal political conflict. The Yale lab’s research showed not only evidence that could indicate genocidal intent but also patterns of deliberately targeting civilians. For policymakers, such reporting can shift allegations to facts.
Jehanne Henry, a veteran Sudan analyst who leads the Reckoning Project’s work in Darfur, described the deluge of evidence coming from the region via smartphones and social media.
“We have seen RSF fighters filming themselves killing civilians and boasting about it. Human rights groups have verified and cross-checked those images, matched them with satellite data, and even identified individual commanders,” she said. “There is no longer doubt about the abuses.”
This convergence of evidence—witness accounts, geolocation, metadata, and satellite imagery—makes it harder than ever for perpetrators to deny crimes. It also makes it easier for those on the ground to act quickly: In some cases, analysts can detect atrocities as they unfold, allowing humanitarian organizations to warn civilians before an attack happens or preserve evidence before it disappears.
But technology is not justice. Satellites can expose atrocities, but they cannot prosecute them. OSINT can verify evidence, but it cannot enforce international law. The gap between evidence and accountability remains vast—not because we lack tools, but because we lack political will to act on what we have in hand and prosecute atrocities.
The challenge now is to integrate digital evidence into formal mechanisms of justice. Courts must adapt to new forms of verification and work more seamlessly with civil society. States must be willing to act on the information that they already have by committing to catching perpetrators. And citizens must demand that crucial data does not remain just pixels on a screen.
As Sudanese lawyer Mutasim Ali told me, “Open-source intelligence and satellite imagery not only serve as evidence—they can save lives when the world fails to act”—going on to say that we must inform people about these incidents both to try to stop atrocities now and to prevent those in the future. He’s right: Technology has become the witness that cannot be silenced, and the question is whether the rest of the world will choose to listen.
