She had written on local affairs for Proceso, Mexico’s leading news magazine, for the past 10 years, and had recently published reports on the drug war in Veracruz between two rival and murderous cartels. Her writing included accusations of local-government corruption.

A few days after her death, the lower house of the Mexican Congress called for a moment of silence in Martinez’s memory and passed legislation meant to protect journalists against assault or intimidation.

More than 80 other Mexican journalists have been murdered since 2000, for reasons largely connected with their reporting on the drug wars. Very few -- almost none -- of these murders have been solved to anyone’s satisfaction.

Journalism in Mexico has become a dangerous and almost impossible occupation when reporters in some areas of the country dare to write about details of organized crime and corruption.

The drug trade has a long history in Mexico, but its menace, power and impunity have surged to an unheard-of level. It is a force that acts from the shadows, and it has neither ideas nor ideals -- only interests and instincts.

Far Beyond Mexico

Its impact and the dangers of confronting it extend far beyond Mexico. In the old days of hegemony by the Institutional Revolutionary Party, a portion of the news media chose self- censorship, for fear of government displeasure or merely to serve its own interests. Now we have the sad paradox that in a Mexico that has become a democracy, journalists must choose between silence or the threat of death. Yet many of them continue to report on the reality faced by the country, like reporters sent to cover events in hell.

The danger to the press and other media from organized crime in Mexico, Central America and some countries of Latin America is an especially fierce stage of a long history of struggle for freedom of expression in the region. Its 19th century military dictatorships hated such freedoms. From their point of view they had good reason. The liberal Latin American press was their constant critic, with ferocious cartoons, satirical sonnets, incendiary articles and excellent writers. Many journalists had to endure ostracism, imprisonment and exile. Some would die for their persistent commitment to political and journalistic freedom.

In the early decades of the 20th century, countries that demonstrated a strong inclination toward democracy -- Chile, Colombia, Costa Rica and Uruguay -- established newspapers that have lasted more than a century. And the new media of radio, in a time of social convulsion, opened up fresh opportunities for free speech -- but also for domination.

On the right, the government of Juan and Eva Peron in Argentina was probably the first to apply the full propaganda force of radio toward the preservation of power. Later in the century, the totalitarian regime of Cuba would use radio and television for its own purposes and eliminate freedom of expression and the once extremely broad spectrum of the Cuban media.

The region’s brutally repressive military regimes during the 20th century were also enemies of a free press. In Argentina and Chile, the generals, who had seized power in military coups, closed newspapers and tortured and murdered journalists.

Intolerant of Criticism

Assaults on freedom of the press in Latin America still occur across the political spectrum. (Among right-of-center governments, Panama has been especially guilty.) The new democratically elected populist regimes in Latin America emphasize social change and generally have charismatic leaders. They have been intolerant of criticism, justified or unjustified, from their opponents.

Hugo Chavez of Venezuela has been the worst offender, through such actions as the expropriation of the independent news agency, RCTV, and a barrage of propaganda pushing his own messianic image. But he has not closed some historically important newspapers, and freedom of expression still struggles to make itself heard in papers such as El Nacional and journals such as Tal Cual.

Many Latin American countries have severe libel laws that have been used to persecute journalistic opponents. President Rafael Correa of Ecuador secured a judgment for libel of $40 million and three years in prison against a writer and three directors of the newspaper El Universo. (In February, he withdrew the charges against the convicted-but-not-yet- imprisoned journalists.)

In Argentina, President Cristina Fernandez de Kirchner has been at odds with much of the media, especially the conglomerate Grupo Clarin SA, and she has favored legislation limiting press freedom. In 2009, though, the Argentine Congress eliminated the charge of criminal defamation, and similar laws imposing prison sentences for libel were overturned in recent years in Brazil, Chile, Colombia and Costa Rica.

Mexico’s Supreme Court now stands firmly in favor of freedom of expression, supporting the argument that the public need to know is the most important issue and that information and criticism, whether severe or even unjust, must be heard. But in Mexico, the struggle on the ground continues. There is freedom of expression, but the heavy footfalls of intimidation trail after too many of journalists. How many more martyrs like Regina Martinez must pay with their lives for their bravery?

Whatever the issues and conflicts, the goal of democracy demands a free press. It should also be unbiased, but that cannot be achieved in all individual cases. It is the unimpeded and entire range of free expression that offers us access to what is true, real and relevant to our countries and ourselves.

*Enrique Krauze is a historian and author of “Mexico: A Biography of Power” and of “Redeemers: Ideas and Power in Latin America.” The opinions expressed are his own. This article was translated from the Spanish by Hank Heifetz