Man Murdered in Texas Led Mexican Cartel While Informing for US, Attorney Claims

Juan Jesus Guerrero Chapa was sitting in the passenger seat of his Range Rover in the parking lot of an upmarket shopping center in suburban Dallas when the assassins came for him. It was just before 7pm on May 22, 2013. While Chapa's wife was loading packages into the vehicle's trunk, a masked gunman stepped out of a white Toyota Sequoia, approached Chapa's side of the car, and shot him several times with a 9mm pistol.

A year later, three Mexican men were arrested in connection with the killing. Today, what exactly Chapa was doing in Texas when he was murdered — and what the nature of his relationship to one of Mexico's most powerful drug cartels was at the time of his death — has been thrown into question by court documents filed by an attorney representing one of his alleged assassins.

Chapa previously served as the personal lawyer to Osiel Cardenas Guillen, the former head of the Gulf Cartel (CDG), a notorious drug trafficking organization based in northeast Mexico. Cardenas was arrested in 2003 and extradited to the United States for prosecution in 2007. He is currently serving a 25-year sentence at the "supermax" federal prison in Florence, Colorado.

Wes Ball, an attorney defending one of the suspects, Jesus Gerardo Ledezma-Cepeda, told VICE News that he has documents from federal authorities that indicate Chapa was working as an informant for the US government. Ball says that he also has proof that Chapa was serving as the "de facto" head of the Gulf Cartel at the same time that he was working with the feds.

"Following Cardenas' arrest, his attorney Chapa was the de facto head of CDG," Ball and another lawyer allege in court documents filed on behalf of Ledezma-Cepeda. "As head of CDG, the deceased Chapa ran a large criminal enterprise whose activities included murders, narcotics trafficking, kidnapping, extortion, bribery, money laundering and torture."

Ball said the documents that support his claim about Chapa's status as the acting head of the Gulf Cartel were filed under seal, and he declined to share them with VICE News. A spokesperson for the US Attorney's Office in the Southern District of Texas, where the case is being prosecuted, declined to comment on the allegations.

Ball also wants to introduce evidence from Chapa's autopsy that indicates that he had cocaine in his body at the time of his death. Ball says the fact Chapa had recently taken cocaine reflects his ongoing involvement in illegal activities, and backs up the allegation that he was serving as the Gulf cartel's interim kingpin.

While evidence of cocaine use is hardly proof that somebody is a cartel boss, the timing of Chapa's killing coincides with a tumultuous period for the Gulf Cartel's leadership. When Cardenas Guillen was extradited to the US in 2007, he negotiated a plea bargain that got him a reduced sentence. It's widely assumed that the information he provided to US authorities as part of the deal triggered a split between the CDG and Los Zetas, a group that Cardenas had created to serve as the cartel's armed wing. The schism led to a bloody war, and Los Zetas emerged as a powerful independent cartel.

Cardenas' cousin Antonio Cardenas Guillen, a.k.a. "Tony Tormenta," and Jorge Eduardo Costilla Sanchez, a.k.a. "El Coss," vied for control of the CDG until the former was killed in 2010. El Coss was captured in 2012, and succeeded by David "El Metro 4" Salgado, who was promptly gunned down in January 2013. Another possible successor was captured in August 2013, three months after Chapa's murder. The arrests and killings created a power vacuum and led to the fragmentation of the cartel, which has since splintered into several warring factions.

The relationship between Chapa and Cardenas went back more than a decade. In 2002, the Mexican newsmagazine Proceso tracked Cardenas' rise to power, attributing it in part to his ability to manipulate the Mexican news media for his own benefit. According to the report, Cardenas would leak information about the cartel's competitors through Chapa, who was described as his lawyer. However, Chapa was not listed as Cardenas' attorney during the Gulf cartel kingpin's legal proceedings in the United States.

At the time of his death, Chapa was living in a $1.2 million mansion in Southlake, Texas — one of the wealthiest areas in the US — with his wife and two teenage kids. The murder plot was apparently a lengthy and sophisticated operation that was hatched as early as March 2011. In the wake of the killing, Southlake Police Chief Stephen Mylett noted that it was clear that the hit was carried out by "an organization trained to do this activity."

Watch the VICE News documentary Cashing in on El Chapo:

Ledezma-Cepeda and his two associates allegedly made repeated trips over the Mexican border to "stalk" Chapa, and rented an apartment in nearby Grapevine, Texas. According to court records, the trio installed a surveillance camera in Chapa's neighborhood and attached a tracking device to the underside of his Range Rover. Court documents state that Chapa had also received phone calls warning that "he had been found by people who wanted to kill him."

Three other fugitives have been charged in connection with the case, but their indictments remain under seal and they have not been identified.

The three detained suspects were captured in September 2014. Ledezma-Cepeda, 58, also known as "Chuy," was arrested with his son, Jesus Gerardo Ledezma-Campano, 30, on the Anzalduas International Bridge, which connects McAllen, Texas with the Mexican city of Reynosa. The pair were on their way back into Mexico. Ledezma-Cepeda's cousin, Jose Luis Cepeda-Cortes, a 58-year-old US resident, was arrested at his home in Edinburg, Texas.

Ball says his client worked as a private investigator in Mexico, usually taking cases that involved surveillance of cheating spouses or tracking down individuals who owed his clients a substantial amounts of money. The attorney declined to say how Ledezma-Cepeda allegedly came to be involved in Chapa's murder. "That's what the trial is going to be about," he said.

According to court documents, Ledezma-Cepeda sent emails that indicate that he and the two other suspects may have also been involved in other murders. In 2012, he had an email in his inbox containing the name "Eliseo Martinez Elizondo." The three men reportedly tracked Elizondo, a local attorney in Monterrey, Mexico, using the same tracking device they used on Chapa. Elizondo was later kidnapped and murdered. In addition to practicing law in Monterrey, Elizondo was linked to casinos in the area.

Documents also allege that Ledezma-Cepeda and his son placed another tracking device under a vehicle belonging to Luis Cortes Ochoa, a former deputy secretary to the minister of public security in San Pedro Garza García, a wealthy municipality near Monterrey. Cortes Ochoa was also murdered. Earlier this year, Moises Tijerina de la Garza – Chapa's brother-in-law – was also murdered in Monterrey. By that time, Ledezma-Cepeda was in custody. However, court documents say he also had Tijerina contact information. Altogether, court documents link the three men to seven other murders or disappearances.

Ledezma-Cepeda's trial is scheduled to begin on April 25. Court documents indicate that attorneys representing his co-defendant Cerpeda-Cortes plan to call nearly 60 witnesses to the stand, including federal agents who can testify to Chapa's alleged "illegal activities" while he served as a US informant.

Follow Tess Owen on Twitter: @misstessowen