On March 15, the Mexican media conglomerate MVS Communications fired award-winning investigative journalist Carmen Aristegui after rejecting her demand that it reinstate two of her colleagues. Daniel Lizárraga and Irving Huerta were fired a week earlier by MVS Radio, which said the two were let go for using the company’s logo without permission in support of MéxicoLeaks, a new whistleblowing platform launched on March 10 by a consortium of five Mexican media outlets and two civic groups.

However, Aristegui and her staff of reporters previously did an investigative report on Mexican President Enrique Peña Nieto’s opulent mansion, which was built by a real estate developer who later won lucrative government contracts. The firing of one of Mexico’s most prominent radio journalists has raised concerns about the country’s return to the “bad old ways” — when the Mexican government could count on the cooperation of media outlets to suppress critical journalistic voices.

In the hours following the 1968 massacre of student protesters by the military and security forces at Tlatelolco plaza in Mexico City, authorities moved swiftly to cover up the killings, confiscating films, unpublished reports and other documents from journalists who covered the demonstration. The government wanted the student problem and news of the bloodshed to disappear: Mexico was preparing to host the 1968 summer Olympics.

It was not until 2002 that the newspaper El Universal published photos from that day from an undeveloped roll of pictures kept secret for decades. The cover-up of the Tlatelolco massacre took place at a time when the media were willing allies of the Institutional Revolutionary Party (PRI) regime, which ruled Mexico for seven consecutive decades. This is one of the main reasons the Tlatelolco massacre, along with countless other atrocities committed during Mexico’s “Dirty War” period, remained shrouded in secrecy for years.

As Peña Nieto and his PRI party’s approval ratings plummet, maintaining a culture of secrecy and silencing dissent appear vital to his political future. In a recent op-ed, “We are All Carmen,” National Autonomous University of Mexico professor John Ackerman made an apt connection between Aristegui’s firing and the upcoming midterm elections in June. Aristegui’s show regularly aired views of opposition parties and covered controversial topics, including the murder last June of 22 individuals in Tlatlaya and the kidnapping and disappearance of 43 students late last year from the Ayotzinapa teacher-training college in Guerrero state.

The scandal also comes at a pivotal moment in the struggle for access to government information on abuses of power in Mexico. Journalists are increasingly using the country’s Transparency Law, which includes a specific clause that mandates disclosure of otherwise classified information on grave violations of human rights, to expose state secrets, corruption and abuses of power.