A sketch of Joaquín “El Chapo” Guzmán, center, during his trial in Brooklyn federal court on Jan. 30. (Jane Rosenburg/Reuters)

Malcolm Beith, a freelance journalist based in Washington, covered the drug war in Mexico from 2007 to 2010 and is the author of “The Last Narco” and “Hasta el último día.”

Despite warnings by the judge in the trial of the drug lord Joaquín “El Chapo” Guzmán to limit unsubstantiated claims of corruption, witness after witness accused three presidents, an official in Mexico’s state oil company and a former federal police chief of taking multimillion dollar bribes — all without providing a shred of corroborating evidence.

The trial is over, and the defense’s case rested on exactly that absence of hard evidence — as well as the credibility of government witnesses. During his closing argument on Jan. 31, defense lawyer Jeffrey Lichtman returned to the accusation that former president Enrique Peña Nieto took a $100 million bribe. He asked why, if such a bribe took place, Guzmán was still hunted down by the authorities, insinuating that it was not Guzmán but another leader of the Sinaloa cartel, Ismael “El Mayo” Zambada, who paid the bribe.

So why have we, the media, been so eager to report and effectively believe these allegations? The allegations by the U.S. government prosecutors’ cooperating witnesses have made waves everywhere — except Mexico. The New York Times wrote about Mexican newspapers’ reluctance to swallow the accusations whole, and Twitter too was abuzz. “Amazing that not one major Mexican newspaper led with the alleged $100 million Chapo bribe to Pena Nieto today,” tweeted one investigative journalist, prompting comments that suggested self-censorship or worse.

Why amazing? It’s quite possible — and, in fact, probable — that the reason the claims aren’t causing a stir in Mexico is because there isn’t any corroborating evidence that they are true. During the trial, both the prosecution and defense failed to follow up with even basic questions. How would one deliver $100 million to a president? Surely someone would have seen 100 briefcases (each one holding about $1 million) or the equivalent stashed in duffel bags and delivered in a truck to the presidential residence or a stash house in the middle of nowhere?

There’s no doubt there is some element of confirmation bias at play in this trial. With each titillating detail of their business, the cooperating witnesses in the Guzmán trial seem to have won over the media. Law enforcement testimony has received scant coverage.

Let’s be honest: Who among us wouldn’t love to have proof that a president took a bribe from a drug lord? It fits into a narrative we often want to believe. Even the current president, Andrés Manuel Lopéz Obrador, denounced during his campaign “the cartel that steals the most: the Los Pinos cartel,” in reference to the presidential palace. Hyperbole, to be sure, but the sentiment is not an unpopular one.

The judge in the Guzmán trial, Brian M. Cogan, at first noted that questioning should take into account the rights of those “individuals and entities” who are not directly involved in the Guzmán case, and save them from any public embarrassment. He later rejected “embarrassment” as a reason to stop political accusations from being hurled. But substance went out the window, too.

Journalists have noted that a former vice president of Colombia, Óscar Naranjo — who also had served as a police chief — was accused by one cooperating witness in an interview with Drug Enforcement Administration agents of accepting payment for protection. He denied the accusation, but it should be noted that when an allegation is made to the DEA in a field office — as Mike Vigil, a former DEA chief of international operations, told me when we were discussing the trial — it has to be written up in a DEA report, regardless of whether the agents believe it has substance.

When it comes to the Guzmán trial and some of its more sensational revelations, it’s best to maintain skepticism on some fronts. Vigil, who knows Mexico well from his time as a DEA agent and has remained on top of developments in the Guzmán case, dismissed the recent rape-of-minors allegations, saying the accuser, identified in media reports as Alex Cifuentes, was just spreading a rumor common in smear campaigns in the criminal underworld.

Vigil was not defending Guzmán, but he was defending the truth, which at times has been elusive in this trial. Random accusations made through the media do not help investigations into human trafficking. While it’s also certainly possible that top officials were corrupted, Guzmán likely didn’t need Peña Nieto’s, or any other president’s, help. At most, as the head of Mexico’s armed forces, the former president could have told his generals and admirals that Guzmán was no longer a top priority. But it’s not possible the DEA, not to mention their counterparts in the Mexican marines, would have just let Guzmán drop off the radar.

“It’s hearsay anyway,” Vigil said, pointing out that no allegation in the trial has come from Guzmán, who in the end did not testify. “It’s all, ‘He said, Chapo said.’ ”

With the exception, of course, of the mountain of real evidence used against Guzmán himself. The accusations of corruption and rape are very serious and should not just be fodder for sensational headlines. Repeating the claims of unreliable sources does not get us closer to the truth. Ultimately, how American prosecutors and investigators, and their Mexican counterparts, choose to follow up on some of the allegations will be crucial to provide justice to the cartels' victims. A footnote in the rape allegation document says other witnesses have corroborated the claims, suggesting the authorities are taking them seriously, and either investigating them or planning to.

Let’s hope they’re up to the task.

Read more:

Malcolm Beith: ‘El Chapo’ could be the key to dismantling drug financial networks

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