AS PERUVIAN PRESIDENT Alberto Fujimori meets today with President Clinton, he'll be spared a sight that has greeted him on previous state visits. The usual White House vigil arranged by thousands of supporters of Lori Berenson, the New York native and MIT student who recently marked the third year of her life prison sentence in Peru, was called off at the last minute. "President Fujimori doesn't pay attention to us marching back and forth," says Rhoda Berenson, the prisoner's mother. "Since he doesn't care what the average citizen thinks, we're focusing now on congressional subcommittees, which determine how much US money goes to Peru." Interestingly, in the last few months Berenson herself -- who was convicted of treason in a closed trial -- has been spared a few of the harsher elements of her prison existence. In October she was transferred from the frigid Yanamayo prison in the Andes to the lower-altitude Socabaya prison a few hundred miles from Lima. And last week four other prisoners were moved into her wing, ending more than 100 days of solitary confinement. But, according to Amnesty International, Berenson awaits treatment for the various medical conditions prison life has inflicted on her -- arthritic hands, bronchial and throat problems, and chronic gastritis.

As prison life grinds on, reporters have stopped making wisecracks on those rare occasions that they take note of Lori Berenson's case. When Berenson was convicted and sentenced in 1996, there was a distinctly arch tone in both press coverage and conversation around New York, a spoiled-Sandalista-gets-in-trouble dismissiveness that portrayed her as an East Coast Patricia Hearst (who celebrated a momentous silver anniversary of her own this week). When John H. Richardson wrote a comprehensive story on the issue for New York, the magazine's cover blared "What's a nice girl like this doing in a Peruvian prison for life?" "And that was one of the betters stories," says Rhoda Berenson. "The commentary early on was really 'what was she doing there anyway?' Because there was really a feeling that she would be out in six months, that they wouldn't really go on with the sentence."

That they have gone on with the sentence may be bound up both in Fujimori's political ambitions and in the unchanging view of Berenson that holds firm, ironically enough, in the country whose cause she took up. Since a defiant televised appearance at her sentencing, Berenson has been held in pretty low regard among the general population in Peru. Last June, when he rejected a proposal by his own Prime Minister, Fujimori said freeing Berenson would send a "negative signal" to the people, and an editorial in yesterday's New York Times claims the Peruvian President is trying both to take control of the country's judicial system and to win an unconstitutional third term in 2000. "Fujimori's popularity has been going down, but the one thing he has going for him is that he's reduced terrorism," says Rhoda Berenson. "So when he wants to show what he's done for the country he can always say 'I put Lori Berenson in prison.'" Of course, that's a concerned mother speaking, but the argument makes sense. There may not be much American diplomacy can do for Peru's assorted miscarriages of justice. But in the early 1990s, when Fujimori suspended the country's constitution, the US found a pretty effective tool -- temporarily eliminating military aid to Peru -- which could be used again. When a borderline tyrant uses an unjustly imprisoned American citizen as an election plank, we've got to exert real diplomatic pressure.