Read a joint statement about this story from the Guardian and Televisa here.

There have been mutterings in Mexico for some time about the bias shown by the country’s main television network, Televisa, in favour of the frontrunner in Mexico’s presidential election, Enrique Peña Nieto. The claims have now been supported by documents seen by the Guardian, which also implicate other politicians in buying news and entertainment coverage.

The perception of bias has triggered a wave of demonstrations. The first was on the afternoon of 23 May, when almost 20,000 people, most of them university students in Mexico City, staged a march against Televisa, to demand the democratisation of mass media. They carried banners saying “We don’t want a soap-opera democracy” and “Informed students will never be manipulated. Peña Nieto will not be imposed upon us.”

The energy that began with this march continued on 10 June, with a massive protest of 100,000 people and smaller marches in 13 other states, timed to coincide with the last round of presidential debates before the 1 July election. Citizens in the streets of Mexico City chanted, “Peña, the TV is yours, the streets are ours,” and said it’s time to “turn off the television”.

Enrique Peña Nieto is the presidential candidate of the Partido Revolucionario Institucional (PRI), the political party that, under various names, kept Mexico under uninterrupted authoritarian rule from 1929 to 2000. In their peaceful protest, the young students denounced Televisa’s intention to impose him as president.

The Mexican spring began a few days before that first demonstration, on 11 May, during a campaign event by Peña Nieto at the Universidad Iberoamericana (Ibero), a high-quality private educational institution run by the Jesuit order. The students shouted at him, “Coward!”, “Ibero doesn’t want you!”, “Murderer!”, reminding him of the repression of villagers from San Salvador Atenco back in 2006, when he was governor of the state of Mexico, just north of Mexico City.

Televisa and the PRI appeared to present these protests as having been orchestrated by Andrés Manuel López Obrador, the presidential candidate of the leftwing parties. The young people responded by posting a video on YouTube, where 131 of them identified themselves for what they were: students. Hence a new movement was born, called #yosoy132 (#Iam132), in support of information democracy.

The relationship between Televisa and the PRI is as close as it is old. More than three decades ago, Emilio Azcárraga Milmo, father of the incumbent CEO of the firm, defined himself as “a soldier of the PRI”.

Televisa is the biggest communications company in the Spanish-speaking world. It controls 70% of the audience in Mexico and 74% of that in the AAA social group. Its news programmes are the leading information source for the Mexican population. Public television is almost nonexistent and the influence of the written press is limited.

Frank Zappa, the musician who died in 1993, used to say that “Politics is the entertainment branch of industry”. If he were to be resurrected in Mexico and saw the kind of relationship that has developed between electronic media and politics, he would undoubtedly reaffirm that. The so-called media-ocracy is a privileged actor in the national political scene and will play all its cards in this year’s presidential election.

Both Televisa and its rival TV station Azteca have assumed an effective role in the forging of candidates for public office, the defining of public policy and even in matters such as public security and citizen mobilisation. Day after day, radio and television broadcasters not only inform, but excommunicate, admonish or hail according to what suits them at the time. They emit opinions, judge and condemn, quite often as part of a paid publicity package presented to the audience as mere information. They act effectively as a great elector, contracted by a sponsor.

They have a number of pundits in their payroll who appear on the screen giving their version of reality and “legitimising” their company’s views. They also maintain a close relationship with polling firms that produce results that, far from being a valid instrument for measuring electoral tendencies, are in fact electoral propaganda. Those polls, according to María Marván, a member of the council of the Federal Electoral Institute, are misleading. “The opinion polls are used to tell lies; they are used in a tricky way,” she said.

The close relationship between Peña Nieto’s candidacy and Televisa, as well as the apparent role of the company in seeking to harm López Obrador’s candidancy, was suspected by several critics and documented by Mexican journalist Jenaro Villami.

Now, those suspicions have been broadened by the Guardian’s report on the subject, and supported on 8 June by evidence presented by Laura Barranco, a reporter who worked for Televisa with Carlos Loret de Mola, the presenter of the station’s leading morning news show. In a radio interview, she said that in an internal electronic chat about one of the documents highlighted by the Guardian, Loret de Mola, who has been a vocal defender of Televisa in recent weeks wrote: “Everything, absolutely everything, is true.” Loret de Mola has denied this.

Televisa’s role in forging Peña Nieto as a presidential candidate was one of the central items in the presidential debate of 6 May, which the two leading television networks didn’t transmit on their highest-rating channels (2 and 13). López Obrador accused his PRI opponent of being a product of television. The former governor denied this and retorted that, if television could make presidents, then López Obrador would have been one.

The accumulating evidence of media manipulation validates the feelings of thousands of young university students who feel they are being tricked by television into voting for a certain candidate. Televisa responded to the Guardian by demanding an apology and writing a letter. Many Mexican citizens think that it is Televisa which owes an apology to the Mexican society.

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