Juan Carlos Mesa Vallejo, also known as “Tom” or “Carlos Chata,” was arrested on December 9 while celebrating his 50th birthday. He was charged with aggravated criminal association, illegally carrying military-grade weapons and use of false documents.

Tom, a career criminal from Bello, a town just north of Medellín, is thought to have taken a leading role within the powerful Oficina de Envigado criminal group earlier this decade. He is being held in isolation after having been transferred to a Bogotá prison. According to El Colombiano, he will likely be extradited to the United States.

Another famous criminal was also present at the birthday party where Tom was arrested: Jhon Jairo Velásquez, alias “Popeye,” a self-confessed hitman for Pablo Escobar who spent more than 23 years in prison before turning himself into a political activist and internet sensation. His presence at a drug capo’s birthday celebration along with other top figures of the Medellín underworld appears to contradict the terms of his parole, meaning the attention-seeking former assassin could once again find himself behind bars.

A Criminal Heavyweight

Tom’s criminal career began with the “Chatas” gang, which he helped create in the 1990s and which he would later lead. Under the rule of Diego Fernando Murillo, alias “Don Berna,” the successor to Pablo Escobar’s empire, the Chatas would come under the banner of the Oficina and develop into a more powerful criminal structure.

After Don Berna was extradited to the United States in 2008, various factions of the Oficina fought each other for dominance. Later, the 2012 capture of Oficina leader Erickson Vargas Cardenas, alias “Sebastian,” allowed Tom to step into a more prominent role in the organization.

“Tom was Sebastián’s military chief … As one of his most trusted men, he gained contacts. It was a succession,” Nelson Matta Colorado, an investigative journalist for El Colombiano, told InSight Crime.

In 2013, the warring factions of the Oficina cemented a truce and formed an alliance with their former rivals, the Urabeños, now the most powerful criminal organization in Colombia. According to the Colombian National Police, Tom was responsible for the trafficking cocaine through Medellín, while the Urabeños took care of shipping the drugs beyond Colombia’s borders.

Matta told InSight Crime that this partnership with the Urabeños offered Tom an additional source of power, in comparison to other Oficina leaders.

“When Tom arrived at the board of criminal directors [of the Oficina], he realized the little power he had over the others,” Matta explained. “So he struck a deal with the Urabeños to gain more influence and criminal backup.”

Soon after the Oficina truce came into force, the United States began targeting Tom and his criminal associates.

In 2014, the US Treasury Department put Tom on its “Kingpin List.” And in 2015, the agency blacklisted the Chatas for “narcotics trafficking and violence in support of the Oficina de Envigado.”

By 2016, the United States was offering a $2 million reward for information that could lead to Tom’s arrest.

Limited Impact?

The internal dynamics of the Oficina de Envigado have often helped shapeMedellín’s security landscape. But despite Tom’s prominence in Medellín’s underworld, his arrest is unlikely to disrupt the Oficina’s criminal activities. Previous arrests of Oficina members of a similar rank as Tom were trumpeted by authorities but ultimately proved to have little impact.

Matta said this is due to the Oficina’s structure, which does not depend on a single figure for leadership.

“Today’s criminal organizations such as the Oficina do not possess a pyramidal structure, but function rather with a board comprised of various directors. So the capture of one of them as just occurred doesn’t impact the whole structure as it used to,” he said.

“The organization hasn’t suffered significant blows to its finances, so when there are arrests, they simply replace one piece with another,” Matta added. “The structure will be maintained, and so will its way of operating, because it’s been a successful criminal model so far.”

While Tom’s arrest won’t lead to the demise of the Oficina, it will likely spur some shifts in the group’s operations. The Urabeños, which are under pressurefollowing a series of arrests of top leaders, will likely be looking for a new local partner in the cocaine trade among the Oficina’s ranks.

Another likely effect of Tom’s arrest is that it will encourage criminals to maintain a low profile to avoid being caught. This is a strategy that other criminal actors in Latin America have adopted with success.

As one commenter said in response to the press release announcing Tom’s arrest, “a living dog is better than a dead lion.”