Bola, one of the highest peaks looking down on Juarez. He put 60 push-to-talk hand-held radios in the hands of cartel enforcers: 30 for Barrio Azteca, 30 for La Linea.

He began having reservations about what he’d done after the cartel targeted Mexican federal police with a car bomb on July 15, 2010. The bombers phoned in a false report that an officer had been shot, luring police and rescue workers to the intersection where a wounded man in a police uniform lay bound and gagged. Unbeknownst to the first responders on the scene, an old Pontiac parked against the curb held 22 pounds of an explosive water-gel called Tovex. Someone in the line of sight of the car bomb detonated it with a cell phone. Two federal policewould have rebuffed him as well, had he not made up a convincing story about another car bomb that got him a meeting with the DEA. By the end of July, he had passed a lie-detector test and was put on the agency’s payroll.

From July to November 2010, EQ was a paid informant of the DEA. He managed to patch his U.S. handlers into the secure telecommunications network that the Juarez Cartel used to organize murders, abductions, drug shipments, arson and even bombings. Thanks to EQ, the DEA listened in on 80 assassination plots. In many cases, the bodies of victims were beheaded, dismembered, or incinerated. The agency listened in for four months, staying up on the wire and delaying the arrest of Benny Gallegos until Nov. 27,