For Latin American drug kingpins, there are few fates as terrible as extradition to the United States.

Former DEA director of operations Mike Braun says of the typical extradited drug trafficker: “Once he’s convicted [in the U.S.], he knows he is going to be spending the rest of his life in prison. He’s not going to have access to a cell phone. He’s not going to be able to run his organization from the direct lines of the federal penitentiary anywhere in the United States. That’s over with. And that is what they fear most.”

Back in 2010, not long after his extradition, Zambada learned that his former Chicago-based colleagues Pedro and Margarito Flores—twin brothers from Little Village who for four years imported two tons of cocaine a month to Chicago, as partners to the cartel—were ready to testify against him. Prosecutors had Zambada’s voice on recorded phone calls, inquiring about payment for heroin and naming names of coconspirators. It would seem the privilege of being El Mayo’s favorite son had made Zambada feel invincible.

In March 2010, attorneys for Zambada traveled to Mexico City to interview Loya Castro in person. In a sworn declaration by one of the attorneys, Loya Castro recalled being told by federal agents that “in exchange for information about rival drug trafficking organizations, the United States government agreed to dismiss the prosecution of the pending case against Mr. Loya-Castro, not to interfere with his drug trafficking activities and those of the Sinaloa Cartel, to not actively prosecute him, Chapo, Mayo, and the leadership of the Sinaloa Cartel, and to not apprehend them. The agents stated that this arrangement had been approved by high-ranking officials and federal prosecutors.”

The DEA has the largest law-enforcement presence abroad of any federal agency. There are 91 DEA offices outside of the United States, including 11 in Mexico. The DEA acts in an advisory capacity to Mexican military and police, supplying real-time intelligence from electronic surveillance and its network of paid informants.

In April 2013, Zambada pleaded guilty to one count of conspiracy to distribute more than five kilos of cocaine and one kilo of heroin—but the U.S. attorney’s office’s kept the plea a secret for a year. In that year, hearings in the case were scheduled and canceled—and both sides simulated proceedings despite knowing the case to be closed. This was done to cloak the reality that Zambada was cooperating with investigators. He knew Mexican military and government officials on the take from the Sinaloa cartel. Even after four years in jail, he could identify who worked for the cartel and in what capacity.