SANTIAGO, CHILE -- Monica Gonzalez lives in constant fear of assassination. She is not a politician or a guerrilla, but a gutsy, independent, 38-year-old journalist working in a country where journalism is virtually the last bastion of legal opposition to military dictatorship and, as a result, a very dangerous trade to ply.

Only recently Gonzalez was released from an 18-day stint in San Miguel prison. She was held in a small cellblock reserved for women suspected of political violations, surrounded by the cells of men who have been convicted of murder and other violent crimes. It was her second time in jail. The cause for her incarceration this time: an interview she had published in a leftist magazine in September. In it a vice-president of Chile's Christian Democratic party allowed as how Augusto Pinochet, the nation's dictator, is a violent, immoral man, and not very intelligent to boot.

The Ministry of the Interior immediately brought a case against Gonzalez under the doctrine of "responsible authority" -- the idea being that she who delivers negative news, like the messenger of ancient times, should be held responsible for its content.

That case will probably never go far but Gonzalez believes that her arrest and temporary imprisonment were intended as a warning to tone down her criticism of the government. After all, it was she who first revealed several years ago that Pinochet was building himself an extravagant presidential palace. Moreover, since her return to Chile in 1977 from three years of exile in France, she has written persistently about some of the worst abuses by the secret police after the 1973 right-wing military coup against Salvador Allende. In other words, Gonzalez is doing what a political opposition might do in the Chilean parliament, if one existed, and saying what international human rights organizations might say, if they could get in to investigate conditions in Chile.

"Of course I am afraid," says Gonzalez. "Very afraid. I worry about someone coming in the middle of the night . . . . But it would do no good to think about this all the time. I have my work to do."

Then there is Marcello Contreras. The editor of APSI, an opposition weekly, he published a special edition a few months ago poking fun at Pinochet and other members of the government. That issue was promptly confiscated, and he and a colleague were charged with slandering not the president, but the commander-in-chief (who is, of course, the same person). That made it possible for the government to send the case to a military court. The military judge jailed Contreras and his colleague for two months, then set them free pending completion of a "psycho-political analysis" of the special edition, meant to provide better insight into their deviant behavior.

No sooner had Contreras returned to work than he found himself the target of right-wing vigilantes. When APSI reprinted a cartoon caricature of God from a Spanish publication, a "theocratic movement" dumped a truckload of residue from shellfish and other garbage at the magazine's front door.

And so it goes for any Chilean journalists who step very far out of line. One magazine editor thought by the government to be especially subversive is permitted to go about his work in the daytime, but must report to jail each night. Several journalists actually have been killed during the past year and a half (one just after an assassination attempt against Pinochet), and government agents are suspected of being the culprits.

Pressing for an extension of its mandate until 1997 in a plebiscite scheduled to be held sometime this year, the junta is making a special effort to render the Chilean press as quiescent as the rest of the body politic. The regime has constructed a network of 34 laws and regulations restricting the media. One of the most notorious prohibits any coverage of the Communist Party or other organizations that, in defiance of Article 8 of Pinochet's constitution, "propagate doctrines that offend the family, propound violence or are based on a totalitarian conception of the state or on class struggle."

These laws are rarely enforced against most of the mainstream newspapers in Chile simply because they censor themselves heavily. The government owns only one newspaper outright, but it has indirect leverage over many others.

El Mercurio, for example, the country's most influential and handsomely produced paper, has been saved repeatedly by government loans and could be ruined financially if those loans were called in on short notice. Thus it comes as no surprise to find full-color photographs of Pinochet and ample quotations from his speeches on the front page of El Mercurio nearly every day. (El Mercurio's funding was also an issue in the early 1970s when it was alleged to have been helped financially by the Central Intelligence Agency, as part of its campaign to weaken Allende.)

With television entirely under government control, radio has carried much of the burden of media opposition to Pinochet's regime for more than a decade. In Santiago alone, there are 25 AM and 25 FM stations, many of them affiliated with the Christian Democratic Party, the Catholic Church, or other opposition groups. Radio, of course, is able to deliver an alternative point of view to remote areas in the far north and far south of Chile that otherwise have little access to non-governmental information.

These broadcast critics of the regime and the several opposition weeklies were joined last year by two new daily newspapers critical of the government -- La Epoca, founded by the Christian Democrats, and Fortin Mapocho, which is published by a moderate faction in the Socialist party.

La Epoca is a sophisticated, European-style newspaper, full of political and international news, which many people hoped would mount a credible journalistic challenge to the military regime. Its editor and publisher is Emilio Filippi, a distinguished Chilean journalist who has won international recognition for his stands on behalf of freedom of the press. But the outlook is bleak for La Epoca given its relatively small circulation and its failure to attract substantial advertising. (Indeed, some corporations and businesses pay La Epoca for advertisements, but then ask the newspaper not to publish them, out of fear of political consequences.) Already the staff has taken drastic pay cuts to help the paper survive.

Fortin Mapocho, which hoped to attract a working class constituency by emphasizing sports, is doing just as badly. Its young staff works on donated computers in a converted house on the edge of Santiago's business district, but their enthusiasm is dampened by a lack of resources. Without rapid relief for their budgets, La Epoca and Fortin Mapocho could soon go under, removing any element of serious opposition from Chile's 30 daily newspapers.

"There is so much to be done," says Monica Gonzalez with a look of serious strain. "I consider myself to be well-informed, but in prison I discovered that I knew nothing about what is really happening in this country." There, Gonzalez says, she found women who had been imprisoned for a year or more -- and, in some cases, tortured -- just because their names had been found in the notebooks of certain members of political organizations.

"Putting me in prison backfired for the government," Gonzalez says. "Now I am more determined than ever to fight for liberty to the end." The trouble is that political apathy in Chile, including in the establishment press, may make her and a few others lonely fighters for a lost cause.

Sanford J. Ungar, dean of the School of Communication at American University, visited Chile in November.