The DEA didn’t intend to tip off a Mexican drug cartel. But in March 2011, José Vasquez Jr., a Dallas native and the leading cocaine distributor in East Texas for the Zetas cartel, gave the trackable BlackBerry PINs of the group’s leaders to American authorities, which the DEA passed to Mexican law enforcement. Miguel Ángel Treviño and his brother Omar, leaders of the cartel, quickly found out they had been betrayed. To retaliate, their operatives killed an estimated sixty people in Allende, a town in the northern state of Coahuila in Mexico—including an 81-year-old woman and her seven-month-old great-grandson—in a massacre that lasted for weeks. 

In The Making of a Massacre, a podcast released today from Audible, ProPublica reporter Ginger Thompson goes inside the scene of the crime in the border town, only forty miles from Eagle Pass in South Texas. “I set out to piece together what really happened in Allende,” says Thompson in the first episode. “And, more importantly, why.”

The podcast is based on Thompson’s reporting for ProPublica and National Geographic, a 2017 piece that told the story of the massacre through the voices of those involved: innocent families living in a town overtaken by the cartel; local officials helpless against the well-armed, well-connected Zetas; cartel members who cooperated with DEA officials and saw their families killed as revenge; and the DEA agent who led the investigation and watched his work lead to the murder of dozens of innocent people.

In the written piece, Thompson and her editor chose to share the tragedy through the words of survivors as a way to communicate the impact of each death beyond a body count. “Unfortunately, the stories of massacres in Mexico are mind-numbingly common,” Thompson, who previously worked as the Mexico City bureau chief for both the New York Times and the Baltimore Sun, told Texas Monthly. “We wanted people to immediately feel like they were reading something different. Instead of me telling the story, we wanted to find a way to allow people who lived on all sides of this massacre to tell the story themselves.”

The choice is effective. Reading about the last moments Claudia Sánchez spent with her fifteen-year-old son, the story’s power comes from Sánchez’s own telling. When Sánchez describes the shirt he was wearing—a recent birthday present, blue to match his eyes—the scene feels all the more visceral. So does her pain and disbelief when Allende’s mayor says he’s sorry, but there’s nothing that local law enforcement can do to help.

Thompson saw the podcast as a chance to tell the story differently. Unlike the oral history, which jumps from the massacre to the backstory to the aftermath, the audio version breaks the story up into five chronological parts. Personal accounts narrate events, largely through the voices of actors. (Most of the interviews were conducted in Spanish.) The oral history gave the characters space to tell their own story beyond a conventional article; the audio format allows participants and actors to communicate outrage and fear through particular mannerisms and details. “When I hear these stories in audio, I get a bit of a gut punch, even more powerfully than in the text,” says Thompson. “I hadn’t realized how much more personal voice is—hearing somebody’s voice gives you a sense of them that is hard to write.”

That’s true for all the voices in the podcast—including that of Thompson herself, a character who didn’t make it into the written piece. Without the expository framework of the article, Thompson provides context for the listener. “Adding myself as a narrator in this story isn’t something I would have felt comfortable doing in a written way—I haven’t done a lot of first-person reporting—but it felt like the right way to take people through this in audio,” she says.

By featuring Thompson, the podcast offers an additional experience for listeners. Through the actors portraying the survivors of the massacre, they hear what it’s like to live in a town controlled by a drug cartel. Through Thompson, they hear what it’s like to report on it: her tentative early conversations with survivors over machaca tacos in their kitchens; her description of a cartel lieutenant as “Arnold Schwarzenegger in Kindergarten Cop”; her masterful, careful pressing of the former mayor, staring him down in his store until he agrees to talk. “One of the wonderful things about the job I get to do everyday is going to a place like Allende and winning the trust of people like these,” says Thompson. “I wanted to give people that experience.” On The Making of a Massacre, listeners aren’t just entering the world of those living beside cartel operatives. They’re also entering the world of an investigative reporter, venturing into dangerous places to uncover the truth.

In the ProPublica story, which was nominated for a National Magazine Award, Thompson raised questions about American accountability in the fight against drug trafficking, and her efforts have prompted action. Since publication, Democratic senators and congresspeople have called for an investigation into the events.

But the piece—and the podcast—also seek to accomplish something more subtle than accountability: a change in how the American public understands the border. The story focuses on a tragedy, but the setting communicates the fluidity of life in South Texas and northern Mexico. Almost all the participants have family members on both sides of the border, including the DEA agent. The voices—American and Mexican—have Latino names. The innocent fifteen-year-old, killed because he was in the wrong place at the wrong time, would have played a football game in San Antonio the next morning. 

Thompson, who grew up in El Paso, is a product of that border culture herself. “I grew up crossing the border. Many people cross the street; I walked across the bridge,” she says. “When you live in these communities, it’s a part of your day-to-day life. You have family reasons and business reasons and cultural reasons to go back and forth all the time.” She hopes readers can understand the dynamics of a place like Allende, both as a town controlled by drug traffickers and as a community that exists across borders. Amid a presidential administration that seeks to maximize the difference between “us” and “them,” that project feels more urgent than ever.