Andrés Manuel López Obrador has never been a fan of the free press. An adversarial politician by nature, Mexico’s president has long claimed to be the target of unfair press coverage and various media conspiracies, including a supposed “information blackout” during the 2006 presidential election, which he narrowly lost. In the runup to last year’s election, López Obrador dismissed some of his critics in the media as “conservatives in the guise of liberals” and “opponents” who should simply “stop pretending.” After he resoundingly won the presidency, many in Mexico thought—perhaps naïvely—that the accomplishment would finally assuage López Obrador’s adversarial impulses. In fact, the opposite happened. During the five-month transition that led to his December inauguration, López Obrador took aim at the press, dousing journalists with verbal abuse (“power mafia,” “adversaries,” “snobbish press,” “intellectually dishonest,” “slick operators of conservatism”). So unrelenting was the barrage that Article 19, a human rights organization that aims to protect freedom of expression and the press, denounced the president-elect’s failure to uphold his “duty” to be “tolerant of criticism.”

Not much has changed since López Obrador formally began his six-year term. When a Wall Street Journal report suggested a severe gasoline shortage could be blamed in part on a decrease in imports from the United States rather than López Obrador’s much-publicized push against huachicoleros, or gasoline smugglers, he quickly accused the Journal of lying. “They are not serious,” he said during one of his long daily early-morning news conferences.

But no organization has faced López Obrador’s ire like the Mexican newspaper Reforma. Over the past couple of months, Reforma has run a series of pieces on a wide range of issues related to the administration, from properties owned by Cabinet ministers that were not disclosed in a timely manner to a recurring feature on murders committed during the new president’s tenure. López Obrador has not handled the criticism well. “They have slandered us,” he recently said of the paper.

“The idea of ‘fake news’ lies at the heart of ‘fake history.’ If he delegitimizes his critics now, they will lack authority in the future.” — Juan Pardinas, editor in chief of Reforma

The confrontation reached a fever pitch last week, when Reforma accused the administration of using Mexico’s equivalent of the IRS to audit some of the newspaper’s owners for a supposed $600 discrepancy in the company’s 2014 fiscal exercise. “Never, in the almost 100-year history of the company, have the owners been personally required to appear for any sort of tax issue,” Juan Pardinas, Reforma’s editor in chief, told me recently. Not surprisingly, Pardinas’ team interpreted the summons as intimidation. The next day, López Obrador blew up. He accused the newspaper of harboring hidden political motives. “I have called them snobbish and I will keep doing it,” he said, defiant, in front of a large group of reporters. López Obrador went on to question Reforma’s history of unbiased journalism, accusing the paper of protecting Carlos Salinas, a corrupt former president, and playing a role in supposedly fraudulent elections.

None of this is true.

Contrary to López Obrador’s aggressive fake-news crusade against the paper, Reforma has been at the forefront of Mexican independent journalism for over a quarter century. “It has always been able to keep a safe distance from political power. They have been critical from day one,” said Carlos Bravo Regidor, a Reforma columnist and journalism professor. Editor and reporter Daniel Moreno agrees: “From its very beginning in 1993, Reforma bet on democracy, transparency, and accountability. The fight against corruption has always been at the core of its editorial mission.” Moreno, who manages Animal Político, an award-winning independent news site that has become the scourge of corrupt Mexican politicians, is part of a long list of eminent reporters and editors who began their careers with the paper, under the tutelage of veteran newsman Alejandro Junco de la Vega. (Disclosure: I began my own career at El Norte, Reforma’s sister publication in Monterrey, Mexico. Both my parents are Reforma columnists.) Junco’s son, Alejandro, now runs the paper.

I spoke with the younger Junco a couple of days after López Obrador’s latest onslaught against Reforma. “Our task is journalistic, not political,” Junco told me. “People in government come and go, but truth endures. In the long run, it guarantees the health of our institutions.”

That mission, apparently, includes the willingness to respond when unfairly confronted by those in power. Last week, after combing through López Obrador’s very specific allegations against the paper, Pardinas and Junco chose to reply with a deceptively simple video. Using the president’s own words as a voice-over, it juxtaposes Reforma’s hard-hitting front pages on the precise topics López Obrador now claims the paper was missing in action over the years. The video, which has been seen almost 1.2 million times on Twitter, is a powerful refutation of the president’s falsehoods. “Confronted with nonsensical accusations, we have evidence in print: hundreds and hundreds of stories and interviews on corruption, fraud, impunity, and, well, authoritarianism,” Junco explained. For Pardinas, López Obrador’s attempt to erode public trust in Reforma and other independent voices (he has also gone after critical experts and civil society organizations) illuminates a larger strategy. “The idea of ‘fake news’ lies at the heart of ‘fake history.’ If he delegitimizes his critics now, they will lack authority in the future,” Pardinas said.

Both Pardinas and Junco plan to keep adding to Reforma’s operation. “We will keep working under the understanding that Mexico is a democracy, whether or not the president agrees,” Pardinas told me. I asked both men if they were concerned by the possibility that López Obrador’s statements could lead to an atmosphere of hostility toward the press, like the one created by Donald Trump in the United States. Pardinas suggested both Trump and López Obrador share the “same hostility against those who disagree or have a different vision of what the country should be.” Junco agreed. “One can certainly draw that parallelism,” he told me. “Trump has called the press the ‘enemy of the people.’ López Obrador does something very similar when he calls us ‘conservatives.’ It’s an act of passive aggression that hides a deep disregard for freedom of expression. What he does is no joke.”

Junco is right, of course. Elected with an almost absolute mandate as Mexico’s first supposedly progressive president, López Obrador should be the first to resist the temptation to intimidate and abuse the free press, especially in a country where journalists see their lives threatened at every turn. That he has fallen prey to his worst populist impulses bodes ill for his presidency, and for the country he governs.