An American citizen appears to be in charge of the Jalisco New Generation Cartel (CJNG), one of Mexico’s most violent criminal organizations, following the killing last month of its co-founder and leader, according to a report this week by The Wall Street Journal.
California-born Juan Carlos Valencia Gonzalez, known by the moniker “03,” is the 41-year-old stepson of slain kingpin Nemesio Oseguera Cervantes, alias El Mencho.
Valencia Gonzalez has been a regional leader within the cartel, with his power and influence making him one of the favorites among security experts and journalists as the natural successor to El Mencho.
Although the Journal report cites official sources from the US and Mexican governments, it is difficult to confirm that he is now the true leader of an organization that has been led by a type of criminal council and features multiple leadership figures within its command.
Valencia Gonzalez rose to prominence after the capture of El Mencho’s biological son, Ruben Oseguera Gonzalez, known as “El Menchito” (Little Mencho), in 2015, who was extradited to the US after five years of confinement in a maximum security prison in Mexico.
In March 2025, a court in the District of Columbia sentenced him to life in prison plus 30 years to be served consecutively for his role in a major drug trafficking conspiracy.
With the fall of what had been the CJNG’s legitimate heir, Valencia Gonzalez emerged as a possible successor among experts and US and Mexican intelligence.
The moniker “03” reflects his relevance and closeness to the upper ranks of power within the CJNG, with “01” being El Mencho’s designation and “02” that of his son, Oseguera Gonzalez.
Additionally, Mexican authorities have reported that Valencia Gonzalez is the primary leader of the “Grupo de Elite,” a powerful and violent armed wing of the CJNG known for its significant firepower and military training.
However, according to security expert David Saucedo, the designation of Valencia Gonzalez as “El 03” is merely a hypothesis with limited support when considering the cartel’s internal functioning.
“I suspect this hypothesis will not materialize. If ‘03’ automatically becomes the new leader of the Jalisco Cartel, he would immediately become a target for authorities. A collective, temporary leadership would have been better so that capture efforts could be spread across four individuals. Concentrating all the attention is not a move I believe ‘03’ would favor. It seems to me it would be in his interest to maintain this collective leadership structure and not draw the full attention of the United States onto himself,” Saucedo told Anadolu.
Following the killing of El Mencho, Mexico’s Security Chief Omar Garcia Harfuch said that authorities were closely watching four possible successors.
Although he did not share any names, experts such as Saucedo had previously indicated that Valencia Gonzalez was among the possible candidates.
Others considered in the line of succession include Ricardo Ruiz Velasco, alias “El Doble R,” at one point seen as the true successor to El Mencho and known as a generator of violence in the country; Hugo Gonzalo Mendoza Gaytan, or “El Sapo,” linked to forced recruitment and torture camps; and Audias Flores Silva, alias “El Jardinero.”
According to Saucedo, if Valencia Gonzalez is indeed the effective leader, the country dodged a literal bullet, as the other runners-up could have plunged the country into further violence.
“If, on the contrary, a transition had favored ‘El Sapo’ or ‘El Doble R,’ then the country would be in turmoil, because they are military-type leaders, warrior figures within the Jalisco Cartel. Within the cartel itself, there are factions—the political, negotiating wing and the shock group, the military ones, those who seek confrontation, those who understand no language other than that of weapons,” he said.