In the jargon of the Brazilian bureaucracy that watches over their every move, they are known as "the annulled ones": critics and opponents of the military government who have been deprived by official decree of their political and civil rights, their jobs and sometimes even their existence in the eyes of the law.

Their ranks include former presidents, labor leaders, scientists, intellectuals, civil servants and military officers. Reduced to obscurity and silence by the measures taken against them, "the annulled ones" are now emerging as the focal point of a noisy and emotional debate that questions the worth and extent of an official "liberalization" program recently announced here.

Under a series of decrees last month by Presiden Ernesto Geisel, a general who has canceled the rights in his four years in power, his successors will be denied such sweeping powers.

Human rights leaders here aruge, however, that Geisel's "reforms" leave unresolved the problems of the nearly 5,000 Brazilians who have already been penalized by "revolutionary punishments" since the military seized power in 1964.

The process is used exclusively against figures that the military does not consider as direct threats to its hold on the country. Those accused of belonging to the Communist Party or urban guerrilla bands usually are jailed or exiled. In several cases they have been tortured or killed.

"Annulments are a national disgrace," says a prominent lawyer here. "On the one hand, they reek of the kind of the McCarthyism you Americans remember as a nightmare. On the other hand, they have certain points in common with the process the Communists, the very people this regime claims it is protecting us from, use to turn someone into an "unperson.'"

Many of the victims say they are subject to official harrassment and surveillance. Although some of them, mostly prominent politicians who have gone into business with friends, may actually have improved their financial situation. Others say their status makes it hard to find work - and that when jobs are obtained,they are soon lost because of interference by the state security apparatus.

Former opposition state assemblyman Wilson Modesto Ribeiro is one of 525 elected officials who have been summarily deprived of their offices and forbidden to comment on "any subject of a political nature." Named in a decree over a decade ago, Ribeiro ended up selling newspapers and magazines from a stand in front of the state legislature building where he had once served.

"I had to buy the newsstand so as not to die of hunger," Ribeiro, the father of 10 children, said recently.

Civil servants have had similar experiences. When Dr. Mario Ribeiro, brother of the minister of education in the civilian government that the military overthrew, lost his political rights, he was fired from a state health department, where he had worked for more than 20 years. Soon afterward, he was removed from his other job, a teaching post at a state medical school.

Finally, the National Health Service took away his credentials altogether and Dr. Ribeiro, who is not related to the ex-assemblyman, was forced to look for work in another field. When he went to a state-run bank looking for a loan to begin his own business, he learned that, as one of "the annulled ones," his credit had also been suspended.

For the 1,312 military men punished for showing "incompathibility with the objectives of the revolution," the situation is different. Considered legally dead, their wives receive a widow's pension from the armed forces. They and their families are prohibited from receiving treatment at hospitals run by the military and their children are not allowed to enroll in military-run schools.

Ex-Air Force Col. Paulo Malta Rezende, expelled from the armed forces in 1964 and deprived of his civil rights five years later, tried to supplement a meager pension by finding work as a civilian pilot. But after seven years of vain efforts, he was informed that a military regulation forbids "annulled" air force pilots from flying even civilian craft. He now is a tutor for high school students.

The process also has been used to eliminate academic dissidents, such as a group of five professors who were punished after protesting a colleague's loss of rights, and another group of 10 leading research scientists at the Tropical Disease Institute here. Their crime: in 1946 they had supported a campaign allegedly led by communists calling for the withdrawal of U.S. military bases from Brazil.

"Being annulled has cut short our careers in this country," says Florestan Fernandes, a prominent sociology professor who was one of 60 academics sanctioned in 1969. "We have been prohibited from doing research, and we bear the stigma of 'politically undesirable elements.'"

Unable to find work in Brazil, some academics have sought work abroad. But when Dr. Luiz Pereira da Silva accepted a post as chief of experimental parasitology at the prestigious Pasteur Institute in France, the Brazilian government initiated a process to strip him of his citizenship on the grounds that he was "working for a foreign power without the authorization of the president of the republic."

The process, which also has provisions for house arrest and cannot be challenged in any court, is supposed to last for 10 years. But under a constitutional amendment that Geisel says will be repealed next year, Brazilians who have already served out their 10 restricted years had their penalties extended indefinitely.

"There are all sorts of things you have to put up with," says a Rio college student whose politician father lost his rights and whose older brother was banished from the country. "Getting a scholarship is out of the question, and you find that there are lots of professors and students who think it wise not to be seen talking to you.

"It's like being stained or tainted," the student adds. "When somebody in your family has been annulled, it's like you're a pariah."