The Bloomberg team that uncovered the Latin American election hacker had no idea what it would find

When they began, they had no idea what they would find.

Andrés Sepúlveda was just a hacker, jailed in Colombia for carrying out dirty tricks in presidential elections — tricks involving malicious software, espionage and violation of personal data. But, according to a Bloomberg investigation, he led sophisticated efforts costing hundreds of thousands of dollars that even included aiding in the election of Mexican President Enrique Peña Nieto.

And that's just one of the elections he says he worked on over an eight-year career. Peña Nieto and his political party all deny knowing or working with Sepúlveda.

“Our idea was … he’s serving 10 years, he must have done something pretty serious," says Jordan Robertson, the lead writer of the series claiming elections throughout Latin America have been rigged for almost a decade. "He must not have been an amateur. Maybe he has a bigger story to tell."

The story that emerged was not one they could have anticipated. What Robertson says quickly became clear over the course of numerous prison interviews and email exchanges was that this hacker felt his hacking was rooted in principle.

"You don't often get that when you're talking to convicted criminals," Robertson says. "He said, ‘Of course I was paid for my hacking, but I am a right winger, that's what I am. I hack for right wing causes because I'm opposed to the leftist movement in Latin America, and the leftist guerillas, the FARC.’"

Once it was clear to the Bloomberg team that Sepúlveda believed he had a larger mission, they knew he had a bigger story.

The reporters investigated the hacker’s claims over the next nine months. They were able to meet with the hacker multiple times in Bogotá. They submitted hundreds of written questions to him, and coordinated efforts to piece the story together.

The claims may amount to an unprecedented account of sophisticated election fraud and a secret history of dirty Latin American presidential election campaigns in Nicaragua, Panama, Honduras, El Salvador, Colombia, Mexico, Costa Rica, Guatemala and Venezuela.

“Every layer was a layer of the onion, the story kept getting weirder and wilder," Robertson says. "And eventually we hit the point where we’d heard the whole story and we said, 'Now how do we go about proving this?'”

That’s when the reporters learned about Sepúlveda's "insurance file." 

It was a private, not-yet-destroyed record of original emails and information about how the hacker did what he told Bloomberg he did: “My job was to do actions of dirty war and psychological operations, black propaganda, rumors — the whole dark side of politics that nobody knows exists but everyone can see.”