SOUTHLAKE -- Juan Jesus Guerrero Chapa, the lawyer shot fatally shot in Southlake in 2013, acted as the “de facto head” of a Mexican drug cartel, running “a large criminal enterprise,” attorneys for one of the men charged in Guerrero’s death allege in a new court filing.

Jesus Gerardo Ledezma-Cepeda, 59, and his son, Jesus Gerardo Ledezma-Campano, 32, and Jose Luis Cepeda-Cortes are scheduled to go on trial April 25 in Fort Worth.

Wes Ball and Warren St. John, the lawyers for Ledezma-Cepeda, wrote in a document filed Sunday that Guerrero “was the attorney for the head of a large international drug cartel known as the Gulf Cartel or CDG.”

Guerrero took over the cartel operations after the arrest of Osiel Cardenas, according to Sunday’s document. Cardenas was sentenced in 2010 to 25 years in prison and forced to forfeit $50 million from a “vast drug trafficking empire” involving thousands of kilograms of cocaine and marijuana, according to an FBI press release.

After taking over for Cardenas, Guerrero “ran a large criminal enterprise whose activities included murders, narcotics trafficking, kidnapping, extortion, bribery, money laundering and torture,” Sunday’s documents alleged.

Guerrero, who was found to have cocaine in his system when he died, was gunned down in the parking lot of Southlake Town Square. He and his wife had just returned to the Range Rover when he was shot multiple times with a 9 mm handgun.

Last week, prosecutors revealed in court filings that Guerrero had been in fear “because he had been found by people who wanted to kill him.”

The conspirators, prosecutors allege, tried early in their search to get the U.S. government to deport Guerrero.

Last week’s documents also stated that a fourth co-conspirator, Luis Lauro Ramirez-Bautista, sent a drug dealer four times from November 2012 to January 2013 to pay Ledezma-Cepeda a total of $38,000.

The plot to kill Guerrero formed as early as 2011, according to case documents.

Before Guerrero’s death, Ledezma-Cepeda, Ledezma-Campano and Cepeda-Cortes had rented a Grapevine apartment, set up a surveillance camera in Guerrero’s Southlake neighborhood and placed a GPS monitor on his car, according to a federal criminal complaint.

The men traveled from Mexico to Southlake between March 1, 2011, and May 22, 2013, with the intent of killing Guerrero, according to the case documents.

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